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Home My WebLink About20150890.tiff STORMWATER MANAGEMENT PLAN FOR CONSTRUCTION ACTIVITIES BONANZA CREEK PRONGHORN 24-7 BOOSTER STATION APRIL 2014 Prepared for: BONANZA CREEK ENERGY OPERATING COMPANY, LLC Denver, Colorado STORMWATER MANAGEMENT PLAN FOR CONSTRUCTION ACTIVITIES BONANZA CREEK PRONGHORN 24-7 BOOSTER STATION APRIL 2014 Prepared for: BONANZA CREEK ENERGY OPERATING COMPANY, LLC 410 17th Street, Suite 1400 Denver, Colorado 80202 Prepared by: LT ENVIRONMENTAL, INC. 4600 West 60th Avenue Arvada, Colorado 80003 (303) 433-9788 TABLE OF CONTENTS 1 .0 CERTIFICATION 1 2.0 INTRODUCTION 2 3 .0 SWMP ADMINISTRATOR 2 4.0 SITE DESCRIPTION 3 4. 1 Nature of Construction Activity 3 4.2 The Proposed Sequence of Major Activities 3 4.3 Area of Disturbance 4 4.4 Soil Description 4 4.5 Existing Vegetation 4 4.6 Location of Potential Pollution Sources 4 4.7 Non-Stormwater Discharges 4 4.8 Receiving Waters 5 5 .0 SITE MAPS 5 6.0 STORMWATER MANAGEMENT CONTROLS 6 6. 1 Identification of Potential Pollutant Sources 6 6. 1 . 1 Disturbed and Stored Soils 6 6. 1 .2 Vehicle Tracking Controls 7 6. 1 .3 Management of Contaminated Soils 7 6. 1 .4 Loading and Unloading Operations 7 6. 1 .5 Outdoor Storage Activities 7 6. 1 .6 Vehicle and Equipment Maintenance and Fueling 7 6. 1 .7 Dust or Particulate Generating Processes or Activities 7 6. 1 . 8 Routine Maintenance Activities 8 6. 1 .9 On-site Waste Management Practices 8 6. 1 . 10 Concrete Truck Washing 8 6. 1 . 11 Dedicated Concrete and Asphalt Batch Plants 8 6. 1 . 12 Non-Industrial Waste Sources 8 6. 1 . 13 Potential Spills 8 6.2 Best Management Practices (BMPs) 9 6.2. 1 Structural Practices for Erosion and Sediment Control 9 6.2. 1 . 1 Erosion Reduction and Control 9 6.2. 1 .2 Sediment Reduction and Control 10 6.2. 1 .3 Detailed Structural and Administrative Site Management Practices 11 6.2. 1 .4 Implementation of Structural Practices 12 6.2.2 Non-Structural Practices for Erosion and Sediment Control 12 6.2.3 Phased BMP Implementation 12 TABLE OF CONTENTS (CONTINUED) 6.2.4 Material Handling and Spill Prevention 13 6.2.5 Dedicated Concrete or Asphalt Batch Plants 13 6.2.6 Vehicle Tracking Control 14 6.2.7 Waste Management and Disposal, Including Concrete Washout 14 6.2.8 Groundwater and Stormwater Dewatering 14 7.0 FINAL STABILIZATION AND LONG-TERM STORMWATER MANAGEMENT 14 7. 1 Reclamation 14 7.2 Post Construction Structural Measures 15 7.3 Final Stabilization 15 8.0 INSPECTION AND MAINTENANCE PROCEDURES 16 8. 1 Inspections 16 8. 1 . 1 Fourteen-day Inspection/Active Stage 16 8. 1 .2 Monthly Inspection/Completed Stage 17 8. 1 .3 Final Stabilization Stage 17 8. 1 .4 Winter Conditions 17 8. 1 .5 Precipitation Event Inspections 17 8.2 Preventive Maintenance 18 8.2. 1 Good Housekeeping 18 8.2.2 Material Storage 19 8.2.3 Waste Removal 19 9.0 EMPLOYEE TRAINING 20 10.0RECORDKEEPING 20 11 .0SWMP REVIEW/CHANGES 20 TABLE OF CONTENTS (CONTINUED) FIGURE FIGURE 1 PRONGHORN 24-7 BOOSTER STATION PAD BMP MAP TABLES TABLE 1 CHEMICAL PRODUCT LIST TABLE 2 BMP SELECTION CRITERIA TABLE 3 STRUCTURAL AND NON-STRUCTURAL BMP CLASSIFICATION TABLE 4 SEED MIXES AND APPLICATION RATES APPENDICES APPENDIX A STORMWATER GENERAL PERMIT COR-030000 AND BONANZA CREEK ENERGY OPERATING COMPANY, LLC FIELD-WIDE STORMWATER PERMIT COR-03C332 APPENDIX B SITE-SPECIFIC INFORMATION APPENDIX C BMP MANUAL APPENDIX D TRAINING LOG 1.0 CERTIFICATION Bonanza Creek Energy Operating Company, LLC (Bonanza Creek) has prepared this Stormwater Management Plan (SWMP) for construction activities at the Bonanza Creek Pronghorn 24-7 Booster Station. "I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations." Signature 4.9etredi. Date SI/a / sZ Name flauij J . L , L. L 6 Title VP - 455e -1 ,%1 I- t Rocky 40 d 4 t Bonanrya Creek Booster Station COR03C332 April 2014.docx 1 2.0 INTRODUCTION LT Environmental, Inc. prepared this SWMP for Bonanza Creek to be used for the Bonanza Creek Pronghorn 24-7 Booster Station in the Denver-Julesburg (DJ) Basin, Colorado. This SWMP was prepared in accordance with good engineering, hydrologic and pollution control practices to ensure the Best Management Practices (BMPs) are selected, installed, implemented, and maintained to protect surface waters. Changes or additions may be required to address changes in conditions in the project area. As a condition of the Colorado Discharge Permit System (CDPS) permit, the provisions identified in this SWMP will be implemented as written and updated as needed from commencement of construction activity until final stabilization is complete. This document contains the required elements of a SWMP associated with Bonanza Creek construction activities, as defined in the CDPS General Permit for Stormwater Discharge Associated with Construction Activity, Authorization to Discharge under the Colorado Discharge Permit System (Permit No. COR-030000, effective July 1 , 2007). The construction of the Pronghorn 24-7 Booster Station will be covered under the existing CDPS Permit COR- 03C332. A copy of the General Permit and a copy the existing COR-03C332 permit issued by the Colorado Department of Public Health and Environment (CDPHE) for this project are provided in Appendix A. 3.0 SWMP ADMINISTRATOR The SWMP Administrator for Bonanza Creek is responsible for developing, implementing, maintaining, and revising the SWMP. The SWMP Administrator has the authority to dedicate the financial and human resources to implement the SWMP. The SWMP Administrator is: Mr. Dave Lillo — Vice President Rocky Mountain Asset Manager, Denver, Colorado Office: (720) 225-6634 Mobile: (970) 590-2190 The SWMP Administrator will ensure the SWMP is followed and will delegate responsibility for coordination of the SMWP inspections and maintenance of stormwater records to the Operations Manager. The Operations Manager will provide support to the SWMP Administrator with the implementation of his SWMP. The Operations Manager is: Mr. Brian Dodek — Environmental Specialist, Denver, Colorado Office: (720) 22.5-6653 Mobile: (303) 483-5486 Bonanza Creek Booster Station COR03C332 April 2014.docx 2 Both the SWMP Administrator and the Operations Manager will manage the SWMP Team. Other foremen or designated personnel may also assist in stormwater inspections and maintenance of records. Overall, the SWMP Team is responsible for: • Implementing spill/upset clean up procedures; • Notification to local authorities and local residents of reportable releases; • Coordinating various stages of BMP P implementation; • Conducting inspections; • Maintenance of all records; and • Coordination of a preventive maintenance program and housekeeping measures. 4.0 SITE DESCRIPTION 4.1 Nature of Construction Activity Bonanza Creek currently owns or leases oil and natural gas mineral rights in the DJ Basin which includes Weld County, Colorado. Individual pad sites are connected by a series of pipelines. Booster stations are built at various intervals along the pipelines to maintain an internal pressure required to maintain a constant flow of gas. A map of the Pronghorn 24-7 Booster Station Pad is provided as Figure 1 . The development of oil and natural gas wells is generally accomplished in three distinct work phases. The first phase is the Construction phase, the second phase is the Production (operation/maintenance) phase, and the third phase is the Abandonment phase with final reclamation. Each work phase is briefly discussed below. 4.2 The Proposed Sequence of Major Activities Approximately four acres of surface terrain will be disturbed during the construction of the Pronghorn 24-7 Booster Station site. The Construction phase includes the following sequence of activities: pad construction through clearing and grading, equipment installation, access road building, and perimeter reclamation. The Production phase includes maintenance activities during oil and natural gas production. Oil and gas wells in the field are projected to produce for approximately 20 to 30 years with pipelines and booster stations possibly in use for longer periods of time. When the oil and/or natural gas production of a well is exhausted it will be abandoned. Once the pipeline and booster station is no longer in use, the pad area will be reclaimed by contouring disturbed soils to conform to the surrounding terrain. • The construction on this site includes pad construction, flow line installation, access road building and perimeter reclamation. Perimeter reclamation is accomplished by Bonanza. Creek Booster Station COR03C332 April 2014.docx 3 contouring disturbed soils to conform to the surrounding terrain, replacing the stockpiled top soil, seeding, and/or mulching of disturbed soil areas in order to reestablish coverage vegetation. • Access roads provide access to the site. Roadwork construction and maintenance are included in this SWMP for the access roads. Road reclamation is accomplished by contouring disturbed soils to conform to the surrounding terrain, replacing the stockpiled top soil, and seeding and/or mulching of disturbed soil areas in order to reestablish coverage vegetation. For stormwater regulation purposes, construction sites have been divided into the following stormwater stages: Active, Completed, and Final Stabilization. Details regarding the stormwater stages are provided in Section 6.2.3 of this SWMP. 4.3 Area of Disturbance The total project area of disturbance is four acres. The site-specific boundaries and areas of disturbance are identified on the site-specific database site maps, specific inspection forms, and history reports. (Appendix B). 4.4 Soil Description The DJ Basin is a large area covering parts of Colorado, Kansas, Nebraska, and Wyoming. Pronghorn 24-7 Booster Station site falls within Weld County, Colorado. Topsoil varies within the area. The Pronghorn 24-7 Booster Station site is classified as Valent sand according to the United States (U.S.) Natural Resources Conservation Service (hap://websoilsurvey.nres.usda.gov/app/). 4.5 Existing Vegetation The site is primarily surrounded by low shrubs and brush rangeland, tall grass, short grass prairie land, sand dune complexes, and occasional crop land. Pre-disturbance ground cover varies from zero to 80 percent (%). 4.6 Location of Potential Pollution Sources The location and description of all potential pollution sources are provided in detail in Section 6. 1 and summarized in Table 1 . 4.7 Non-Stormwater Discharges The following is a summary list of non-stormwater discharges which are allowed under the stormwater permit: • Discharges from emergency fire-fighting activities or a fire hydrant; • Landscape irrigation or return flow; Bonanza Creek Booster Station COR03C332 April 2014.docx 4 • Uncontaminated springs; and • Construction dewatering. In the event construction dewatering is required at the site, the following conditions will be met: • BMPs will be installed to control stormwater pollution; • The discharge will not leave the site as surface runoff, to surface waters, or to storm sewer systems; and • The groundwater being pumped will not be contaminated so as to exceed state groundwater standards. If the construction dewatering activity cannot meet these conditions, the appropriate permitting will be completed through the state. Additional dewatering information is provided in Section 6.2.8 . Bonanza Creek does not anticipate any non-stormwater discharges at the Pronghorn 24-7 Booster Station site. 4.8 Receiving Waters The stormwater discharged may directly impact tributaries to the South Platte River. The Pronghorn 24-7 Booster Station site does not intrude or encroach on any wetland acreage. If a wetland is designated to be within a pad construction area, Bonanza Creek will consult with the U.S. Army Corp of Engineers, as applicable. 5.0 SITE MAPS The site map is kept in the Bonanza Creek database. The Bonanza Creek database is intended to manage and track all site-specific stormwater records for Bonanza Creek. The database consists of current inspection forms with supporting Microsoft® Visio map attachments. Maps are updated at every inspection interval and dated to show changes from one inspection to the next. For the purposes of this SWMP, the site-specific map information (Appendix B) required to be included in the SWMP will actually be comprised of the Bonanza Creek database. Construction site boundaries; ground surface disturbances; areas of cut and fill; storage areas for building materials, equipment, soil or waste; structural BMP locations; non-structural BMP locations (as applicable); locations of springs, streams, wetlands or other surface waters; wellhead locations; and other pertinent site-specifics are shown on maps attached to the site- specific SWMP Inspection Reports (Appendix B). Bonanza Creek Booster Station COR03C332 April 2014.docx 5 6.0 STORMWATER MANAGEMENT CONTROLS 6. 1 Identification of Potential Pollutant Sources To identify, evaluate, and assess potential sources of stormwater runoff pollutants that may exist at a pad site, the following activities and pollutant sources were evaluated: • Disturbed and stored soils; • Vehicle tracking controls; • Management of contaminated soils; • Loading and unloading operations; • Outdoor storage activities; • Vehicle and equipment maintenance and fueling; • Dust or particulate generating processes or activities; • Routine maintenance activities; • On-site waste management practices; • Concrete truck washing; • Dedicated concrete and asphalt batch plants; • Non-industrial waste sources; and • Potential spills. Refer to the site specific map found in Appendix B for the location of these potential pollutant sources onsite if applicable. 6. 1 .1 Disturbed and Stored Soils Disturbed soil and excavated materials will be stored on or next to the pad within the construction area. Topsoil and other soils will be stockpiled separately and seeded as needed. Excavation in sensitive areas may be conducted using special techniques as specified by the landowner/agency representative. Excavated materials will be utilized as backfill when practical. An exception may be excess rock generated by rock blasting excavation activities. In these areas, some select backfill materials may be required to protect the project area. Excess rock may be pushed into rock filter dikes, used in energy dissipation zones below culverts, constructed into rock check dams within grassed swales, or distributed over a portion of the project area. Bonanza Creek Booster Station COR03C332 April 2014.docx 6 All cut slopes made during construction will be re-graded and contoured to blend into the adjoining landscape and natural drainage patterns will be reestablished to as near pre-disturbance levels as possible. Temporary workspace areas will be restored to approximate pre-construction conditions. 6. 1 .2 Vehicle Tracking Controls Properly constructed and graveled roads provide the best off-site tracking control. Access road entrances adjacent to paved county roads are often graveled to prevent or minimize any off-site soil tracking from pad areas or access roads. In some instances, cattle guards are used to drop off caked mud before the vehicle exits the site area. If tracking is observed, the roads will be cleaned by any combination of road scraping/sweeping as necessary. 6.1 .3 Management of Contaminated Soils If contaminated soils are excavated at the Pronghorn 24-7 Booster Station site, additional BMPs will be employed to ensure containment of any stormwater runoff. In addition, stockpiles of contaminated soil will be removed from the site and disposed of. 6. 1 .4 Loading and Unloading Operations Loading and unloading activities mostly include racks and equipment. In the event of a spill, the SWMP material handling and spill prevention procedures will be followed (see Section 6.2.4). Other activities include unloading of drill pipe, completion pipe (casing), and natural gas line pipe, which are not potential pollution sources. 6. 1 .5 Outdoor Storage Activities The most common substances that could be stored on the site are: 1 ) fuel and lubricants used by vehicles and construction equipment; 2) hydraulic fracturing fluids (surfactants, friction reducers, hydrochloric acid, and potassium chloride) used during well completion procedures; 3) production water from the well; and 4) produced crude oil and condensates. A list of chemical products typically used at a Bonanza Creek site is included as Table 1 . 6. 1 .6 Vehicle and Equipment Maintenance and Fueling Bonanza Creek will not fuel or maintain construction-related vehicles or equipment located within the DJ Basin, Colorado, at the Pronghorn 24-7 Booster Station site. 6.1 .7 Dust or Particulate Generating Processes or Activities Dust and/or particulates generated from vehicle traffic on graveled access roads may produce fugitive emissions. Dust and particulate generation are highest during dry and hot times of the year. If dust from vehicle traffic on graveled access roads becomes significant, dust suppression procedures will be implemented that include road watering. Bonanza Creek Booster Station COR03C332 April 2014.docx 7 6.1.8 Routine Maintenance Activities Routine maintenance activities involving fertilizers, detergents, fuels, solvents, and oils are not completed at the Pronghorn 24-7 Booster Station site. Herbicides may be applied annually in some areas to control noxious weeds. Herbicide application will always be conducted by certified and trained individuals and with consideration for runoff potential to nearby surface waters. 6.1.9 On-site Waste Management Practices All waste from materials imported to the construction site are placed in appropriate containment and then removed for disposal/recycling to an appropriate licensed disposal/recycling facility. No waste materials will be buried, dumped, or discharged to waters of the state. 6.1 . 10 Concrete Truck Washing Concrete truck/equipment washing, including the concrete truck chute and associated fixtures and equipment, is not conducted at the Pronghorn 24-7 Booster Station site or within the Bonanza Creek Permit Area in the DJ Basin, Colorado. 6. 1 . 11 Dedicated Concrete and Asphalt Batch Plants No dedicated concrete or asphalt batch plants are located at the Pronghorn 24-7 Booster Station site or within the Bonanza Creek Permit Area in the DJ Basin, Colorado. 6.1.12 Non-Industrial Waste Sources Cleanup of trash and discarded materials will be conducted as noticed. Cleanup will consist of patrolling the roadway, access areas, and general work areas in order to pick up trash, debris, scrap, or other discarded materials. All waste from materials imported to the construction site are placed in appropriate containment and then removed for disposal/recycling to an appropriate licensed disposal/recycling facility. This also includes sanitary sewage facilities (typically portable), which will be placed, anchored, and maintained with proper care. 6.1.13 Potential Spills Spills or leaks will be handled by Bonanza Creek personnel or contractors, according to the Bonanza Creek Weld County, Colorado, Spill Prevention, Control, and Countermeasure (SPCC) Plan. Bonanza Creek personnel conduct discharge prevention measures, including procedures for routine handling of products. Loading and transfer issues are discussed in monthly safety meetings. Preventive maintenance is scheduled by the SWMP Operations Manager. As part of the preventive maintenance program, Bonanza Creek personnel conduct monthly inspections for good housekeeping issues, operation and maintenance issues, and the condition of structural controls, specifically around tanks and containers. Bonanza Creek Booster Station COR03C332 April 2014.docx 8 Operators are trained in the safe handling of materials and spill discovery, response, and cleanup procedures during safety meetings. Emergency numbers are posted at the Evans office, located at 4301 Industrial Parkway, Colorado. In general, small spills will be handled by Bonanza Creek personnel. The SWMP Operations Manager or designee will handle spills and emergencies. In most cases, an absorbent material is used to pick up the spill. The spill response equipment is also located at the Evans office. In the situation of a larger spill, the SWMP Operations Manager would be notified and a contractor would be called to respond to the spill. For the protection of spill response personnel, all drums, tanks, and other containers are clearly labeled to identify contents, in the event of a spill. Materials handling is discussed in detail in Section 6.2 .4 of this SWMP. 6.2 Best Management Practices (BMPs) BMPs for sediment and erosion control will be accomplished through a combination of construction techniques, vegetation and re-vegetation, administrative controls, and structural features. Typical configurations of structural controls discussed below and technical drawings with references are provided in the BMP Manual (Appendix C). BMP selection is guided by the criteria listed in Table 2 and depicted on the site-specific maps in Appendix B. Structural and non-structural BMPs are discussed in the following sections and are summarized in Table 3 . 6.2. 1 Structural Practices for Erosion and Sediment Control Structural practices primarily include physical attributes of a site designed to reduce erosion and control stormwater or sediment movement. 6.2.1 .1 Erosion Reduction and Control Construction of a pad requires the removal of vegetative cover and topsoil, thereby increasing peak flood flows, water velocity, and the volume of stormwater runoff. An increase in water runoff volume and velocity results in increased erosion. Erosion reduction and control will be accomplished by using all or combinations of various erosion control methods. These methods include, but are not limited to the following: • Diversion and control of run-on water; • Diversion and control of runoff water; • Vegetation establishment and maintenance; and • Application and maintenance of mulches, blankets, tackifiers, tracking, and contouring. Runoff control procedures that will be used to mitigate and reduce the erosive transport forces of stormwater during and after construction of a pad may include but will not be limited to the following: Bonanza Creek Booster Station COR03C332 April 2014.docx 9 • Check dams; • Berms; • Culverts; • Culvert protection/inlet protection/outlet protection; • Diversions; • Land grading/terracing; • Mulches, with or without a tackifier; and • Erosion control blankets. Existing vegetation cover and topsoil are removed only where necessary for the operation of equipment and construction of the pad. Trees and large shrubs that are not cleared from the pad area will be protected from damage during construction by avoiding them with equipment. For example, the blade of a bulldozer will be in a raised position except for designated areas. Trees will be cut or trimmed only to facilitate clearing, grading, and safe installation of a pad. Trees outside the area of disturbance will not be cut, but may have overhanging limbs trimmed if necessary. Refer to Tables 2 and 3 for a list of BMPs to be used throughout the SWMP. Appendix C includes details on BMP installation and maintenance procedures. 6.2. 1 .2 Sediment Reduction and Control The reduction and control of sediment contained in stormwater runoff will be accomplished by the use of sediment containment systems. Sediment containment systems are hydraulic controls that allow the detention of suspended particles via gravity, filtering or entrapment. Sediment controls that will be used to mitigate and control sediments generated from the erosive transport forces of stormwater during and after construction of a pad may include but will not be limited to the following: • Silt fence; • Straw bales; • Wattles; and • Vehicle tracking controls/cattle guards. Refer to Tables 2 and 3 for a list of BMPs to be used throughout the SWMP. Appendix C includes details on BMP installation and maintenance procedures. Bonanza Creek Booster Station COR03C332 April 2014.docx 10 6.2. 1 .3 Detailed Structural and Administrative Site Management Practices The following structural and administrative site management practices are expected to reduce, minimize, and control erosion and sediment transport: • In order to minimize disturbances associated with installation of pads, level and gently sloping terrain outside the construction project area will not be graded, except where necessary. • To prevent tracking of sediment mud and rocks onto public roads, portions of access roads may be graveled, as appropriate. Other means such as track pads/angular rock or cattle guards may be utilized if appropriate. • Silt barriers (e.g. wattles, silt fence, straw bales) will be installed as needed on down- gradient portions of project areas. • Side hill cuts (cut slopes) will be kept to a minimum to protect local resources while providing a safe and stable plane for the efficient and safe use of equipment. • Where conditions warrant, erosion control structures such as berms, diversion structures or culverts may be constructed to divert water away from project areas. These control structures will also reduce soil erosion along and adjoining areas disturbed during construction. • During construction near perennial streams, lakes or wetlands, the utilization of silt fence or straw bales may be considered in order to prevent suspended sediments from reaching down slope watercourses, streams, lakes, or wetlands. • Where appropriate, staked straw bales or silt fence may be constructed adjacent to crossings to reduce potential sedimentation in streams or wetlands. • In areas that have steep slopes, water bars, or runoff diversions may be installed. When used, water bars will generally begin and end in undisturbed ground at approximately a 2% slope. • Culverts may be installed at a grade ranging from 2% to 5%. Inlet protection may include inlet aprons and rock armoring around the culvert perimeter while below grade inlet sumps may be installed to enhance sediment deposition. Outfall protection may include the use of a rock bather to slow the discharge of runoff water. Culvert pipe or outfall protection will be extended to the toe of the slope on the discharge end. • During the reclamation of a pad, cut and fill slopes in steep terrain will be graded and contoured to blend into the adjoining landscape. Natural drainage patterns will also be recreated to as near pre-disturbance as possible. When possible, cut and fill slopes will be constructed so they are no steeper than a 1 to 3 ratio. • Reclaimed pads may have a fence constructed around areas that have been seeded. These fences will be installed in order to keep livestock and vehicles off reseeded areas. Bonanza Creek Booster Station COR03C332 April 2014.docx 1 1 6.2. 1 .4 Implementation of Structural Practices The following structural practices (sediment controls) may be utilized at disturbed areas: silt fences, straw bales, earth berms, or equivalent sediment controls. These sediment control structures will be installed so as to protect down slope surface waters, wetlands, and roads from sediment flow due to runoff from a precipitation or snow melt event. Graded surfaces, walls, dams and structures, vegetation, erosion and sediment control measures, and other protective devices identified in the plan will be maintained, repaired, and restored as necessary. Table 3 contains a summary list of structural and non-structural BMPs. 6.2.2 Non-Structural Practices for Erosion and Sediment Control Erosion and sediment control can also be controlled via non-structural BMPs. Non-structural BMPs are not engineered as a stormwater barrier but are capable of limiting the amount of potential pollutants available to reach receiving water bodies. Non-structural BMPs can achieve the same effect as structural BMPs through erosion control, filtration trapping, and the settling of sediment load within a perimeter. Bonanza Creek has implemented non-structural practices for stormwater management into their site development, including Program Oversight, Construction Site Planning and Management, and Materials Management. Table 3 summarizes the details of such practices. Sites can include a slope to the reserve pit or a buffer zone of natural vegetation used as a non- structural BMP to inhibit sediment travel offsite and minimize the footprint of the pad. 6.2.3 Phased BMP Implementation The phases of construction or development and stormwater stages are linked to the implementation of structural and non-structural BMPs. For stormwater regulation purposes, construction sites have been divided into the following stormwater stages: Active, Completed, and Final Stabilization. Stormwater controls to be used for each phase are listed in Tables 2 and 3 . Approximately 4 acres of surface terrain will be disturbed during the construction of the Pronghorn 24-7 Booster Station. The Construction phase includes the following sequence of activities: pad construction through clearing and grading, equipment installation, access road building, and perimeter reclamation. During active construction and other field work activities, the focus will be primarily on containment type BMPs. An example would be a continuous berm to contain stormwater pollutants on site. During this phase, stormwater runoff is specifically controlled so as not to leave the pad site. The completed phase includes the production (operation and maintenance) activities during natural gas production. Reclamation activities during this phase include maintenance of Bonanza Creek Booster Station COR03C332 April 2014.docx 12 revegetated areas and maintenance of the erosion and sediment control structures. Wells in the field are projected to produce for approximately 20 to 30 years with pipelines and booster stations possibly in use for longer periods of time. When the oil and/or natural gas production of a well is exhausted it will be abandoned. Once the pipeline and booster station are no longer in use, the pad area will be reclaimed by contouring disturbed soils to conform to the surrounding terrain and subsurface pipelines will be removed to the appropriate locations and plugged. For the purposes of this SWMP and the stormwater construction general permit, only active and completed sites will be monitored. Once a completed site is revegetated and stable, it will be removed from the stormwater construction permit program. Depending upon the site conditions and the phase of construction, different stormwater BMPs will be utilized. Various BMP options are listed in Table 2, and design specifications are depicted in the BMP Manual (Appendix C). 6.2.4 Material Handling and Spill Prevention An SPCC Plan is required for this project site as it does meet the applicability criteria set forth in Section 112. 1 of 40 CRF Part 112 and in the Colorado Storage Tank regulations. These regulations require a SPCC Plan for non-transportation related facilities that could reasonably expect to discharge oil into or upon a navigable body of water of the United States; and the facility has a total combine above ground storage tank capacity of greater than 1 ,320 gallons of oil. Both regulations further add that an SPCC Plan is required if any single aboveground oil storage tank's capacity exceeds 660 gallons. Hazardous materials and petroleum products used in construction of a pad include fuel and lubricants for construction equipment and vehicles; small quantities of paints and solvents; water or gel based hydraulic fracturing fluids (surfactant, friction reducer, dilute hydrochloric acid, potassium chloride) used during well completion; produced water; and crude oil/condensate. Safety Data Sheets (SDS) for materials to be used or that are produced, are maintained at Bonanza Creek's, Evans, Colorado office. If a spill of pollutant(s) threatens stormwater or has the potential to discharge from the site, the Stormwater Operations Manager will be contacted immediately. 6.2.5 Dedicated Concrete or Asphalt Batch Plants Bonanza Creek does not have or subcontract any dedicated concrete or asphalt batch plants for its pad site development or construction in the DJ Basin, Colorado, nor will stormwater encounter concrete or asphalt batch plant activities. Dedicated concrete or asphalt batch plants are further discussed in Section 6. 1 . 11 of this SWMP. Bonanza Creek Booster Station COR03C332 April 2014.docx 13 6.2.6 Vehicle Tracking Control Bonanza Creek will employ BMPs to minimize vehicle tracking. Further discussion on this topic is in Section 6. 1 .2 of this SWMP. 6.2.7 Waste Management and Disposal, Including Concrete Washout Waste disposal is further discussed in Sections 6. 1 .9 through 6. 1 . 12 of this SWMP. Concrete washout does not occur at Bonanza Creek's sites, and therefore, will not be a potential pollutant to stormwater. 6.2.8 Groundwater and Stormwater Dewatering Construction dewatering may take place on a limited basis at Bonanza Creek sites. The permit allows for conditional discharge of construction dewatering to the ground (to infiltrate), however no groundwater from construction dewatering can be discharged as surface runoff or to surface waters. For large construction projects with planned dewatering activity, Bonanza Creek will apply for a separate dewatering permit from the state, as required. 7.0 FINAL STABILIZATION AND LONG-TERM STORMWATER MANAGEMENT 7.1 Reclamation Unless otherwise directed by the landowner or a jurisdictional authority, rocks, cut vegetation, and other surface material temporarily stockpiled during construction will be redistributed as backfill on the project area. During reclamation, sediment BMPs will remain in use. Disturbed areas will be seeded using seed mixes appropriate to the location as noted in Table 4, unless the landowner wishes to return the land to agricultural production. Local soil conservation authorities with the U.S. Natural Resources Conservation Service, surface owners and/or reclamation contractors familiar with the area may be consulted regarding the other seed mixes to be utilized. On terrain where drill seeding and/or thatch/mulch is appropriate, seed may be planted using a drill equipped with a depth regulator to ensure proper depth of planting. The seed mix will be evenly and uniformly planted over the disturbed area. Drilling will be used where topography and soil conditions allow operation of equipment to meet the seeding requirements of the species being planted. Broadcast seeding will occur on steep terrain and on areas where the cut vegetation and rocks were redistributed over a right-of-way. Hydraulic mulch consists of applying a mixture of shredded wood fiber or a hydraulic matrix, and a stabilizing emulsion or tackifier with hydro-mulching equipment, which temporarily protects exposed soil from erosion by raindrop impact or wind. Hydraulic mulch is suitable for disturbed areas requiring temporary protection until permanent stabilization is established, and disturbed areas that will be re-disturbed following an extended period of inactivity. Seeding will be done when seasonal or weather conditions are most favorable according to schedules identified by the jurisdictional authority, reclamation contractor, or landowner. Bonanza Creek Booster Station COR03C332 April 2014.docx 14 Whenever possible, seeding will be timed to take advantage of moisture, such as early spring or late fall, which will benefit from winter precipitation. Seed mixes will be planted in the amount specified in pounds (as noted in Table 4) of pure live seed per acre. No primary or secondary noxious weeds will be in the seed mix. The reestablishment of vegetative cover as well as watershed stabilization measures will be scheduled during the working season and before the succeeding winter. Re-vegetation will be accomplished as soon as practical following the reclamation of a pad, pipeline, or road. Mulch will be laid down during re-vegetation as appropriate. The cut vegetation and rocks will act like mulch in the areas where they are applied. Where straw or hay mulch is applied, the mulch will be applied and crimped into the soil. The need for fertilizers will be determined in conjunction with the landowner. If fertilization is necessary, the rates of application will be based on site-specific requirements of the soil. A special condition exists for pad sites within crop lands. According to the CDPHE Stormwater Fact Sheet dated July 2007: ...when portions of an oil and gas site are restored to crop land in accordance with the COGCC rules, and returned to the control of the farmer following interim reclamation, permit coverage is no longer required for those areas, and it is not necessary for the oil and gas site to either stabilize or reassign permit coverage for the areas. When this condition exists for a site, inspections will be discontinued and the site will be removed from the stormwater construction permit program. 7.2 Post Construction Structural Measures Permanent culverts, trench plugs and/or other permanent structural measures may be installed on steep slopes and at wetland and stream crossing boundaries. After restoration and reclamation work is complete, required repairs to vegetation and erosion and sediment control BMPs will be completed as required. 7.3 Final Stabilization According to stormwater regulations, "finally stabilized means that all ground surface disturbing activities at the site have been completed and all disturbed areas have been either built on, paved, or a uniform vegetative cover has been established with an individual plant and a density of at least 70% of pre-disturbance levels, and the vegetation cover is capable of providing erosion control equivalent to pre-existing conditions, or equivalent permanent, physical erosion reduction methods have been employed." A special condition exists for oil and gas pad sites regarding pavement. According to the CDPHE Stormwater Fact Sheet dated July 2007 : Bonanza Creek Booster Station COR03C332 April 2014.docx 15 Areas developed as stabilized unpaved surfaces as needed for operation of the facility after interim reclamation also qualify as 'finally stabilized ". The term "stabilized unpaved surfaces " includes dirt road surfaces and the portions of the well pad surfaces that cannot be revegetated due to operational necessity, but does not include slopes, ditches and other areas where revegetation is necessafy. Stabilized unpaved surfaces must be prepared in such a way as to minimize erosion, such as preventing rill erosion on pad surfaces or roads. 8.0 INSPECTION AND MAINTENANCE PROCEDURES 8.1 Inspections Inspections will be conducted to document the status of erosion and sediment control structures and re-vegetation efforts. Inspection forms will document non-compliance conditions, including any uncontrolled releases of sediment or other contaminants, additional BMPs that are needed, or repair and maintenance issues. Required actions or modifications, as documented on the SWMP Inspection Report, will be implemented as soon as possible, immediately in most cases, to minimize the discharge of pollutants. Routine inspections may be conducted at pad areas and along access roads and pipelines during all phases of work and after a precipitation-related event. All inspection observations will be recorded on the SWMP Inspection Report. The SWMP Inspection Report provides a standardized format that will be completed during all inspections, and includes a signature line for the inspector to ensure compliance with the regulations. For stormwater regulation purposes, construction sites have been divided into stormwater inspection stages: Active, Completed, and Final Stabilization. Each of these stormwater inspection stages is discussed below. Once a Completed site is revegetated and stable, it will be removed from this stormwater construction permit program and all site-specific structural BMPs will be removed. A special condition exists for pad sites within crop lands, which is detailed in Section 7. 1 of this SWMP. When pad sites are being returned to a farmer for agricultural usage, the sites may be removed from the stormwater construction permit program. Personnel responsible for inspections will be trained to evaluate stormwater management concerns, erosion and sediment control BMPs, and to evaluate pad and surrounding area vegetation. 8.1.1 Fourteen-day Inspection/Active Stage The construction phase of work is classified as the Active phase, according to stormwater regulations. The inspection frequency is every 14 days during the Active phase and must be conducted within 24 hours after the end of any precipitation or snowmelt event that causes surface erosion. The construction perimeter, disturbed areas, and any stored materials that are exposed to precipitation will be inspected for evidence of, or the potential for pollutants to possibly enter the Bonanza Creek Booster Station COR03C332 April 2014.docx 16 drainage system. Erosion and sediment control systems identified on the site-specific SWMP Inspection Report will be inspected to ensure they are in good condition and operating properly. 8. 1 .2 Monthly Inspection/Completed Stage Once the site meets the following criteria, but final stabilization is not achieved due to a vegetative cover that has not become established, a thorough inspection will be conducted at least once every month, and post-storm event inspections are not required. This reduced inspection schedule is only allowed if: • All construction activities that will result in surface ground disturbance are completed; • All activities required for final stabilization, in accordance with the SWMP, have been completed, with the exception of the application of seed that has not occurred due to seasonal conditions or the necessity for additional seed application to augment previous efforts; and • The SWMP has been amended to indicate those areas that will be inspected in accordance with the reduced schedule. However, because slopes and other disturbed areas are not vegetated, erosion in these areas still occurs which requires maintenance activities such as regrading, erosion control blankets, and seeding of problem areas. As such, inspections must continue in order to address these situations. The SWMP for the site must be amended to indicate the areas that will be inspected at this reduced frequency. 8. 1 .3 Final Stabilization Stage Final stabilization is reached when all ground surface disturbing activities at the site have been completed, and uniform vegetative cover has been established with an individual plant density of at least 70% of pre-disturbance levels, or equivalent permanent, physical erosion reduction methods have been employed. When the site has reached final stabilization, all temporary site- specific BMPs that are no longer required will be removed. 8.1 .4 Winter Conditions Inspections will not be required where construction activities are temporarily halted because snow cover exists over the entire site for an extended period as long as melting conditions do not exist. The following information must be documented in the inspection record for use of this exclusion: dates when snow cover occurred, date when construction activities ceased, and date melting conditions began. 8.1.5 Precipitation Event Inspections Active site inspections will be conducted within 24 hours after a precipitation or snowmelt event that causes surface erosion. Surface erosion generally occurs when precipitation or snowmelt results in surface water flow. If no construction activities will occur at a site following a storm Bonanza Creek Booster Station COR03C332 April 2014.docx 17 event, post-storm event inspections will be conducted prior to re-commencing construction activities, but no later than 72 hours following the stoi In event. 8.2 Preventive Maintenance Preventing stormwater from passing through pad areas where contamination may occur is a key element of preventative maintenance. Another key element of preventative maintenance is the routine inspection and repair of erosion and sediments control structures. Regular cleaning of diversion ditches and other BMPs to keep them free of debris and sediment will be practiced. Spillways and culvert systems will also be routinely cleaned and inspected (if applicable). These maintenance procedures will help to ensure that the stormwater does not leave disturbed areas via unintended channels. The following preventive maintenance procedures will be implemented, as applicable, to reduce or eliminate potential stormwater contamination sources that may exist on the pad: • Storage containers, fuel tanks, and equipment used during construction activities should be visually inspected routinely for obvious leaks. These inspections should be conducted by site and contractor personnel as they perform their routine duties; • Drums will be properly labeled so an enclosed substance can be quickly identified. Occupational Safety and Health Administration (OSHA)-approved labeling and sign systems will be followed for all secondary containers; • Erosion damage to the berms, outfalls, silt bathers, collection channel, containment ponds, and any other erosion and sediment controls will be repaired as soon as practical; • Areas of stained soil will be inspected in order to identify the sources of the staining. Contaminated soil will be removed and properly disposed; • Energy dissipating material such as riprap, cobbles, or gravel will be placed, or existing materials will be utilized at the stormwater outfalls to prevent erosion damage. Barrow ditches should be free from vegetation and debris which may cause impounding of stormwater; and • Stonnwater management structures will be cleared of debris and repaired when necessary; and surface runoff controls such as culverts and ditches will be used to control runoff. 8.2. 1 Good Housekeeping In accordance with BMPs that provide procedures to eliminate contamination and direct, divert, and contain stormwater, Bonanza Creek has implemented a number of housekeeping practices. These practices will help prevent soil sediment, trash, and toxic or hazardous substances from entering navigable waters. Housekeeping practices include regular cleaning, organization, and maintenance of equipment and erosion and sediment control structures throughout the project. Areas where chemicals are Bonanza Creek Booster Station COR03C332 April 2014.docx 18 stored and used at the site should be stored in buildings or containers where there is limited potential for stormwater contact. The following items will be addressed in order to maintain a clean and orderly pad during the development, production, and abandonment phases of work: • Inspect pad areas routinely; • Correct deficiencies noted during inspections; • Clean and maintain stormwater management structures and components; • Routine trash collection and proper disposal; • Familiarize employees and contractors with spill clean-up equipment and storage locations; and • Familiarize employees and contractors with good housekeeping procedures and pad pollution prevention procedures. 8.2.2 Material Storage The following good housekeeping practices will be followed at the material storage areas: • Storage containers will be stored away from direct traffic to prevent accidents. They will also have proper labels; • Dumpsters and trash receptacles will be enclosed in order to prevent the dissemination of refuse; • Storage areas will be kept free of refuse; • Chemical substances used at pads will be properly labeled and will have proper spill containment; and • Chemical substance containers will be clearly labeled with an SDS kept on file. 8.2.3 Waste Removal All waste from materials imported to the construction site will be removed for disposal/recycling to an appropriate licensed disposal/recycling facility, including sanitary sewage facilities (typically portable). No wastes of imported materials will be buried, dumped, or purposely discharged to waters of the state. There are no other pollutant sources from areas other than construction areas. Bonanza Creek Booster Station COR03C332 April 2014.docx 19 9.0 EMPLOYEE TRAINING Bonanza Creek will inform and train employees who are involved with SWMP activities. Training will cover information and procedures contained in the SWMP and will be conducted on an as-needed basis. Personnel work responsibilities will be used to identify the appropriate attendees. Safety and environmental elements of the SWMP will also be covered. A Training Log (Appendix D) will be kept and updated on an annual basis. The following topics may be presented and discussed during SWMP training: • Introduction to CDPS Stormwater Permit; • Stormwater regulations; • Purpose of stormwater permit; • Requirements of stormwater permit; • Components of the SWMP; • Identification of potential pollutant sources; • BMPs; • Preventative maintenance; • Good housekeeping; • Inspections and maintenance; and • Recordkeeping. 10.0 RECORDKEEPING The following recordkeeping procedures will be implemented in order to provide accurate and complete documentation of events associated with the stonuwater management program. Routine inspections will include the 14-day, monthly, and post precipitation event inspections. Stormwater related inspection records, site maps, and diagrams will be also kept on file or in the Bonanza Creek database. All stormwater related records will be filed and stored by Bonanza Creek for a minimum of three years after each individual site has achieved final stabilization 11.0 SWMP REVIEW/CHANGES Bonanza Creek will amend the SWMP whenever there is a significant change in design, construction, operation, or maintenance, which has a significant effect on the potential for the discharge of pollutants to water of the state, or if the SWMP proves to be ineffective in achieving Bonanza Creek Booster Station COR03C332 April 2014.docx 20 the general objectives of controlling pollutants in stormwater discharges associated with pad activities. The SWMP is considered a "living document". Bonanza Creek Booster Station COR03C332 April 2014.docx 21 FIGURES / • ♦ ♦ ♦ O` / //> z'/ c ,', I: ':: .: •:::=:•. 1 ` _ ;S `,�•: �_ / //// / ! t I � 1 :.-::: ::.,.:-' ♦ � � _ / / / i :::$:::`:::••. 1 / / / I 4570 I 1 : .♦:.::;: ♦ e % • ..- / / I ♦ I ♦ 1 •-:-.::%:.•i L':. I / • , _/ / /• III"'' ;�.::;: ::::::S • ♦ ♦ % ♦ .. • % ♦ I I �:•.• :*►.;:::S .•! ♦ ♦♦ - illas s - ♦ 14% I II •• s...' ,.*.:• .., , :-a.;:•::::.:•..,• •••.•.'•♦.• " 5 456 % S / ;: 1 h Ill �'.�,.•:: :�,: • rr III. = :. ' .. ...!... *:::"....i.-#.?:: :' : ' :' .-. .y::•::• •::::::::::;::::: :ty.':• : -:/. `: ..•. :•=.;:4560:: ;v:' III : I: • , .{•::•:::.:A::..:'•: N:::,: ' '.•�, �•�"+ .. '�'•:-'••'��` . • ♦''•nr-arint •�♦ • • 7, ` �• ♦ .4. a• / ` NOTE: 1 ) GROUND ELEVATIONS ARE BASED ON OBSERVED GPS ELEVATION (NAVD 1988 DATUM). 2) NO ALLOWANCE HAS BEEN MADE FOR SOIL EXPANSION OR COMPACTION. 3) PROPOSED ELEVATION DOES NOT ACCOUNT FOR TOP SOIL REMOVAL. 4) TOP SOIL VOLUME ASSUMES 12" DEPTH ACROSS ENTIRE LOCATION. 5) FILL SLOPES 2:1 6) CUT SLOPES 1 .5: 1 LEGEND 0 100 200 I SURFACE TOPOGRAPHY I r Feet -- WATTLES FIGURE 1 - - - - PROPOSED CONTOUR SITE LOCATION MAP PRONGHORN 24-7 BOOSTER STATION PAD BMP MAP - r EXISTING CONTOUR SECTION 7, TOWNSHIP 5N , RANGE 61W ": . r FILL AREA WELD COUNTY, COLORADO BONANZA CREEK ENERGY OPERATING COMPANY LLC P:\Bonanza Creek Energy1GISWXD\334511303_STORMWATER1034511003_FIGURE_O1_PRONGHORN_BOOSTER_STATION.mxd TABLES TABLE 1 CHEMICAL PRODUCT LIST PRONGHORN 24-7 BOOSTER STATION DJ BASIN, COLORADO BONANZA CREEK ENERGY OPERATING COMPANY, LLC SDS Product Name Manufacturer's Product Use/Chemical Description Chemical Manufacturer Product Number FUELS & LUBRICANTS Acetylene Fuel Various Chain Oil Lubricant Various Diesel Fuel Fuel Various Drive Chain Fluid Lubricant Various Gear Oil Lubricant Various Grease Lubricant Various Hydraulic Oil Lubricant Various Motor Oil Lubricant Various Propane Fuel Various PAINTS Paints - Industrial Enamel Paint Various Paints - Various Colors Paint Various Paints - Primer Primer Various Paints - Thinner Paint Thinner Various MISCELLANEOUS Antifreeze Various uses Various Methanol Various uses Various Rig Wash Various uses Various Starting Fluid Various uses Various Thread Dope Various uses Various WD-40 (Aerosol) Various uses Various WD-40 (Liquid) Various uses Various TABLE 2 BMP SELECTION CRITERIA PRONGHORN 24-7 BOOSTER STATION DJ BASIN, COLORADO BONANZA CREEK ENERGY OPERATING COMPANY, LLC ACTIVE COMPLETED I FINAL. STABILIZATION WC a Booster Station V Berm Berm Berm Cattle Guard Cattle Guard Cattle Guard Check Dams Check Dams Culverts Culvert Protection Culvert Protection Diversion Ditch/Ditch&Berm Ditch&Berm Ditch&Berm Revegetation Erosion Control Blanket Erosion Control Blanket Mulches, with or without a tackifier Land Grading Land Grading Mulches, with or without a tackifier Mulches, with or without a tackifier Revegetation Revegetation Silt Fence Roadside Ditches Vehicle Tracking Control Silt Fence Straw Bales Straw Bale Wind Erosion Control Wattles Wattles Access Roads Berm Berm Berm Cattle Guard Cattle Guard Cattle Guard Check Dams Check Dams Culverts Culverts Culverts Culvert Protection Culvert Protection Culvert Protection Ditch&Berm Ditch&Berm Ditch&Berm Gravel Surfacing Erosion Control Blanket Erosion Control Blanket Revegetation Land Grading Land Grading Mulches, with or without a tackifier Silt Fence Revegetation Straw Bale Silt Fence (Cattle Guard) Straw Bales Wind Erosion Control Wattles Notes: BMP = Best Management Practice TABLE 3 STRUCTURAL AND NON-STRUCTURAL BMP CLASSIFICATION PRONGHORN 24-7 BOOSTER STATION DJ BASIN, COLORADO BONANZA CREEK ENERGY OPERATING COMPANY, LLC NON-STRUCTURAL BMPs Program Oversight Construction Site Planning and Management Good Housekeeping/Materials Management Construction Phase Plan Review Timing of Projects General Construction Site Waste Management Contractor Training and Certification Construction Sequencing Spill Prevention, Control Plan and Countermeasure Database Development and Maintenance Site Operator BMP Inspection and Mainentance Training Non-structural practices may include, but are not limited to: a stabilized staging area, minimize initial pad site acreage, slope pad to the reserve pit, wind erosion and dust control, temporary vegetation, permanent vegetation, mulching, geotextiles, sod stabilization, slope roughening, vegetative buffer strips, protection of trees, and preservation of mature vegetation. A water source may be used to abate dust and alleviate wind erosion. STRUCTURAL BMPs Erosion Control Sediment Control Runoff Control Berms Silt Fence Berms Check Dams Straw Bales Check Dams Culverts Land Grading Culverts Culvert Protection Vehicle Tracking Control Culvert Protection Diversions Wattles Ditch&Berm Land Grading Mulches, with or without a tackifier Erosion Control Blankets Notes: BMP = Best Management Practice TABLE 4 SEED MIXES AND APPLICATION RATES PRONGHORN 24-7 BOOSTER STATION DJ BASIN, COLORADO BONANZA CREEK ENERGY OPERATING COMPANY, LLC SEED MIX APPLICATION RATE (lbs/acre) PBSI Dryland Aggressive Mix (20%) Green Needlegrass, Lodorm (20%) Slender Wheatgrass, Native (20%) Western Wheatgrass, Native 25 (20%) Pubescent Wheatgrass, Luna (20%) Intermediate Wheatgrass, Oahe/Rush PBSI Native Prairie Mix ■ (25%) Blue Grama (10%) Buffalograss (20%) Green Needlegrass 15 (20%) Sideoats Grama (25%) Western Wheatgrass PBSI Native Sandyland Mix (20%) Yellow lndiangrass (10%) LittleBluestem (10%) Indian Rice Grass (10%) Sideoats Grama 15 (10%) Sand Lovegrass (10%) Prairie Sandreed (20%) Switchgrass PBSI Premium Irrig. Pasture Mix #1 (75%) Meadow Bromegrass, Paddock/Fleet 25 (25%) Orchardgrass, Elsie/Megabite/Paiute Notes: lbs/acre = pounds per acre = percent PBSI = Pawnee Buttes Seed Inc. tr7 APPENDIX A STORMWATER GENERAL PERMIT COR-030000 AND BONANZA CREEK ENERGY OPERATING COMPANY, LLC STORMWATER PERMIT COR-03C332 STATE OF COLORADORISCHARGE PERMIT SYSTEM (CDPS) STORM WATER DISCHARGE of Colo Deal�ated to protecting and improving the health and environment at the peop,e at Colorado er e' ASSOCIATED WITH CONSTRUCTION: 4300 Cherry Creek Dr S ACTIVITIES APPLICATION Denver, Colorado 80246-1530 • .,; • Phone (303) 692-2000 • is-6 • Permit COR030000 TDD Line (303) 691-7700 Colorado Department Located m Glendale. Colorado of Public Health Cert#CO R03C332 nttp:rlwww.cjphe.state.co.us and Environment RENEWAL REAPPLICATION -- RESPONSE REQUIRED THE CDPS GENERAL PERMIT FOR STORMWATER DISCHARGES ASSOCIATED WITH CONSTRUCTION ACTIVITIES (COR030000) WILL EXPIRE JUNE 30, 2012 AND WILL BE ADMINISTRATIVELY CONTINUED AT THAT TIME. For Additional Information, see the Q&A Guidance : http://www.cdphe.state.co.us/wq/PermitsUnit/PermittingWhatsNew.htm • This reapplication form shows the current record for the facility listed on page 2 - active certification COR03C332 • For certification COR03C332 to be administratively continued, this reapplication must be reviewed, corrected (if needed), signed, and returned to the division prior to March 31, 2012. This is the only action necessary to renew this certification. • If certification is no longer needed, please send in an inactivation form as soon as the facility is eligible. • Receipt of this form will be tracked on the Division's web site: http://www.cdphe.state.co.us/wq/PermitsUnitJconstruction.html . Select: Active Storm water Construction Certifications (this list will be updated in the first week of each month). A date entry under "Application Received" indicates the date the Division received this renewal application. This also indicates that the certification is administratively continued. • A postcard will be sent to confirm the Division's receipt of the form a certification is administratively continued. Please allow up to 45 days for receipt of this confirmation. • Certifications for which no renewal is received will expire and be terminated effective June 30, 2012. • Please keep a copy of this application for your records. Please direct questions to cdphe.wgstorm@state.co.us, (303) 692-3517, or visit our website at www.coloradowateraermits.com. fvlail to: CDPHE/WQCD Attn Permits. 4300 Cherry Creek Dr South Denver CO 80246 Photo copies, faxed copies, pdf copies or emails will not be accepted by the Division. REVIEW AND CONFIRM THE FOLLOWING INFORMATION IS CORRECT (Verify That This Information Is Correct. Cross out and make changes as necessary.) APPLICATION to RENEW CERT ti COR03C332 1. CONTACTS: PERMITTEE ORGANIZATION FORMAL NAME Bonanza Creek Operating Co LLC LEGAL CONTACT (This is the party who must sign on page 2, Kerry A McCowen, VP 410 17 St Ste 1500 Denver CO 80202 Phone 72O-27-9-233O Email kam@bonanzacrk.com LOCAL CONTACT jd,C- `IYO1;4OC Kerry McCowen, VP Rocky Mountain Ops Phone 720-2.79-2330 Email kam@bonanzacrk.com 7)O • =: , Organization: i Mailing Address: City: _ State: Zip: CONTINUE TO BACK OF FORM Construction SW Renewal Application 2012 Cert ##COR03C332 Bonanza Creek Operating Co LLC Facility Bonanza Creek Drilling Program 2007 R62W page 2 BILLING CONTACT Kerry A. McCowen, VP Bonanza Creek Operating Co LLC 41017 St Ste 1500 • Denver CO 80202 Phone 720 -2338 Email kam@bonanzacrk.com Tao• WO-610D 2. PERMITTED PROJECT/FACILITY INFORMATION Verify That This Information Is Correct. Cross out and make changes as necessary: Project/Facility Name Bonanza Creek Drilling Program 2007 R62W Address Or Cross Streets Hwy 39 & 90 City Uninc County Weld Zip Code 80634 Facility Latitude 40/40/11 Longitude 104/38/45 Total Area Of Project Site (Acres):1,280 Area Of Disturbance (Acres) 6 Nature Of Construction Activity Oil and Gas Production and/or Exploration Immediate Receiving Water(S):Box Elder Creek Ultimate Receiving Water(S): South Platte River 3. SIGNATURE OF PERMIT LEGAL CONTACT "I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is to the best of my knowledge and belief, true, accurate and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations." "I understand that submittal of this application is for coverage under the State of Colorado General Permit for Stormwater Discharges Associated with Construction Activity for the entirety of the construction site/project described and applied for, until such time as the application is a ded or the certification is tir ansferred, inactivated, or expired." / -� XX �,7 de �% _ 1-4 3 --/ d / fT Signature of L ally Responsible Person listed in item 1 (submission must include original signature) Date Si Signed g ir'ic' I # �.,CaP`PA/ ail/M (4 n Ar Name (printed) Title Per Regulation 61 In all cases,APPLICATION shall be signed as follows: a) In the case of corporations, by a responsible corporate officer. For the purposes of this section, the responsible corporate officer is responsible for the overall operation of the facility from which the discharge described in the application originates. b) In the case of a partnership, by a general partner. c) In the case of a sole proprietorship, by the proprietor. d) In the case of a municipal,state, or other public facility, by either a principal executive officer or ranking elected official WQCD Mail Code 2034 Kerry A McCowen, VP Or environmental permitting representative for: Bonanza Creek Operating Co LLC 41017 St Ste 1500 Denver, CO 80634 Page 2 of 22 Permit No. COR-030000 CDPS GENERAL PERMIT STORMWATER DISCHARGES ASSOCIATED WITH CONSTRUCTION ACTIVITY AUTHORIZATION TO DISCHARGE UNDER THE COLORADO DISCHARGE PERMIT SYSTEM In compliance with the provisions of the Colorado Water Quality Control Act, (25-8-101 et seq., CRS, 1973 as amended) and the Federal Water Pollution Control Act, as amended (33 U.S.C. 1251 et seq.; the "Act"), this permit authorizes the discharge of stormwater associated with construction activities (and specific allowable non-stormwater discharges in accordance with Part I.D.3 of the permit) certified under this permit, from those locations specified throughout the State of Colorado to specified waters of the State. Such discharges shall be in accordance with the conditions of this permit. This permit specifically authorizes the facility listed on page 1 of this permit to discharge, as of this date, in accordance with permit requirements and conditions set forth in Parts I and II hereof All discharges authorized herein shall be consistent with the terms and conditions of this permit. This permit and the authorization to discharge shall expire at midnight, June 30, 2012. Issued and Signed this 31 St day of May, 2007 COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT Lea Janet S. Kieler Permits Section Manager Water Quality Control Division SIGNED AND ISSUED MAY 31 , 2007 ADMIX ' STiAT IVE, LY EFFECTIVE JULY 1 , 2007 CONTINUED EFFECTIVE JULY 1 , 2012 TABLE OF CONTENTS PART I A. COVERAGE UNDER THIS PERMIT 3 1 . Authority to Discharge 3 a) Applicable Sections 3 b) Oil and Gas Construction 3 2. Definitions 3 3. Permit Coverage Without Application — Qualifying Local Programs 3 a) Applicable Sections 3 b) Local Agency Authority 4 c) Permit Coverage Termination 4 d) Compliance with Qualifying Local Program 4 e) Full Permit Applicability 4 4. Application, Due Dates 4 a) Application Due Dates 4 b) Summary of Application 4 5. Permit Certification Procedures 4 a) Request for Additional Information 4 b) Automatic Coverage 5 c) Individual Permit Required 5 d) General vs. Individual Permit Coverage 5 e) Local Agency Authority 5 6. Inactivation Notice 5 7. Transfer of Permit 5 8. Reassignment of Permit 5 9. Sale of Residence to Homeowners 6 10. Permit Expiration Date 6 1 1 . Individual Permit Criteria 6 B. STORMWATER MANAGEMENT PLAN — GENERAL REQUIREMENTS 6 C. STORMWATER MANAGEMENT PLAN — CONTENTS 7 1 . Site Description 7 2. Site Map 7 3. Stormwater Management Controls 8 a) SWMP Administrator 8 b) Identification of Potential Pollutant Sources 8 c) Best Management Practices (BMPs) for Stormwater Pollution Prevention 8 4. Final Stabilization and Long-term Stormwater Management 9 5. Inspection and Maintenance 10 D. TERMS AND CONDITIONS 10 1 . General Limitations 10 2. BMP Implementation and Design Standards 10 3. Prohibition of Non-Stormwater Discharges 11 4. Releases in Excess of Reportable Quantities 11 5. SWMP Requirements 1 1 a) SWMP Preparation and Implementation I I b) SWMP Retention Requirements 1 1 c) SWMP Review/Changes 1 1 d) Responsive SWMP Changes 12 6. Inspections 12 a) Minimum Inspection Schedule 12 b) Inspection Requirements 13 c) Required Actions Following Site Inspections 13 7. BMP Maintenance 13 8. Replacement and Failed BMPs 14 9. Reporting 14 -2a- TABLE OF CONTENTS (cont.) 10. SWMP Availability 14 11 . Total Maximum Daily Load (TMDL) 14 E. ADDITIONAL DEFINITIONS 15 F. GENERAL REQUIREMENTS 16 1 . Signatory Requirements 16 2. Retention of Records 16 3. Monitoring 16 PART II A. MANAGEMENT REQUIREMENTS 17 1 . Amending a Permit Certification 17 2. Special Notifications - Definitions 17 3. Noncompliance Notification 17 4. Submission of Incorrect or Incomplete Information 18 5. Bypass 18 6. Upsets 18 7. Removed Substances 18 8. Minimization of Adverse Impact 18 9. Reduction, Loss, or Failure of Stormwater Controls 19 10. Proper Operation and Maintenance 19 B. RESPONSIBILITIES 19 1 . Inspections and Right to Entry 19 2. Duty to Provide Information 19 3. Transfer of Ownership or Control 19 4. Modification, Suspension, or Revocation of Permit By Division 20 5. Permit Violations 21 6. Legal Responsibilities 21 7. Severability 21 8. Renewal Application 21 9. Confidentiality 21 10. Fees 21 11 . Requiring an Individual CDPS Permit 22 -2b- PART I Permit - Page 3 Permit No. COR-030000 PART I A. COVERAGE UNDER THIS PERMIT 1 . Authority to Discharge Under this permit, facilities are granted authorization to discharge stormwater associated with construction activities into waters of the state of Colorado. This permit also authorizes the discharge of specific allowable non-stormwater discharges, in accordance with Part I.D.3 of the permit, which includes discharges to the ground. This includes stormwater discharges from areas that are dedicated to producing earthen materials, such as soils, sand and gravel, for use at a single construction site (i.e., borrow or fill areas). This permit also authorizes stormwater discharges from dedicated asphalt batch plants and dedicated concrete batch plants. (Coverage under the construction site permit is not required for batch plants if they have alternate CDPS permit coverage.) This permit does not authorize the discharge of mine water or process water from such areas. a) Applicable Sections: In accordance with Part I.A.3 of this permit, some parts of this permit do not apply to sites covered under a Qualifying Local Program, as defined in I.A.2.d. For sites not covered by a Qualifying Local Program, all parts of the permit apply except Part I.A.3. The permittee will be responsible for determining and then complying with the applicable sections. b) Oil and Gas Construction: Stormwater discharges associated with construction activities directly related to oil and gas exploration, production, processing, and treatment operations or transmission facilities are regulated under the Colorado Discharge Permit System Regulations (5CCR 1002-61), and require coverage under this permit in accordance with that regulation. However, references in this permit to specific authority under the Federal Clean Water Act (CWA) do not apply to stormwater discharges associated with these oil and gas related construction activities, to the extent that the references are limited by the federal Energy Policy Act of 2005. 2. Definitions a) Stormwater: Stormwater is precipitation-induced surface runoff. b) Construction activity: Construction activity refers to ground surface disturbing activities, which include, but are not limited to, clearing, grading, excavation, demolition, installation of new or improved haul roads and access roads, staging areas, stockpiling of fill materials, and borrow areas. Construction does not include routine maintenance to maintain original line and grade, hydraulic capacity, or original purpose of the facility. c) Small construction activity: Stormwater discharge associated with small construction activity means the discharge of stormwater from construction activities that result in land disturbance of equal to or greater than one acre and less than five acres. Small construction activity also includes the disturbance of less than one acre of total land area that is part of a larger common plan of development or sale, if the larger common plan will ultimately disturb equal to or greater than one and less than five acres. d) Qualifying Local Program: This permit includes conditions that incorporate qualifying local erosion and sediment control program (Qualifying Local Program) requirements by reference. A Qualifying Local Program is a municipal stormwater program for stormwater discharges associated with small construction activity that has been formally approved by the Division. Other Definitions: Definitions of additional terms can be found in Part I.E. of this permit. 3. Permit Coverage Without Application — for small construction activities under a Qualifying Local Program only If a small construction site is within the jurisdiction of a Qualifying Local Program, the operator of the construction activity is authorized to discharge stormwater associated with small construction activity under this general permit without the submittal of an application to the Division. a) Applicable Sections: For sites covered by a Qualifying Local Program, only Parts 1 .A. 1, 1 .A.2, 1 .A.3, I.D. 1 , I.D.2, 1.D.3, 1.D.4, I.D.7, I.D.8, I.D. 11, I.E and Part II of this permit, with the exception of Parts II.A. 1, 11.B.3, II.B.8, and II.B10,10, apply. PART I Permit - Page 4 Permit No. COR-030000 A. COVERAGE UNDER THIS PERMIT (cont.) b) Local Agency Authority: This permit does not pre-empt or supersede the authority of local agencies to prohibit, restrict, or control discharges of stormwater to storm drain systems or other water courses within their jurisdiction. c) Permit Coverage Termination: When a site under a Qualifying Local Program has been finally stabilized, coverage under this permit is automatically terminated. d) Compliance with Qualifying Local Program: A construction site operator that has authorization to discharge under this permit under Part I.A.3 shall comply with the requirements of the Qualifying Local Program with jurisdiction over the site. e) Full Permit Applicability: The Division may require any operator within the jurisdiction of a Qualifying Local Program covered under this permit to apply for and obtain coverage under the full requirements of this permit. The operator must be notified in writing that an application for full coverage is required. When a permit certification under this permit is issued to an operator that would otherwise be covered under Part I.A.3 of this permit, the full requirements of this permit replace the requirements as per Part I.A.3 of this permit, upon the effective date of the permit certification. A site brought under the full requirements of this permit must still comply with local stormwater management requirements, policies or guidelines as required by Part I.D. 1 .g of this permit. 4. Application, Due Dates a) Application Due Dates: At least ten calendar days prior to the commencement of construction activities, the applicant shall submit an application form as provided by the Division, with a certification that the Stormwater Management Plan (SWMP) is complete. One original completed discharge permit application shall be submitted, by mail or hand delivery, to: Colorado Department of Public Health and Environment Water Quality Control Division WQCD-Permits-B2 4300 Cherry Creek Drive South Denver, Colorado 80246-1530 b) Summary of Application: The application requires, at a minimum, the following: 1) The applicant's company name; address; telephone number; and email address (if available); whether the applicant is the owner, developer, or contractor; and local contact information; 2) Project name, address, county and location of the construction site, including the latitude and longitude to the nearest 15 seconds of the approximate center of the construction activity; 3) Legal description or map of the construction site; 4) Estimates of: the total area of the site, the area of the site that is expected to be disturbed, and the total area of the larger common plan of development or sale to undergo disturbance; 5) The nature of the construction activity; 6) The anticipated start date and final stabilization date for the project; 7) The name of the receiving water(s), or the municipal separate storm sewer system and the ultimate (i.e., named) receiving water(s); 8) Certification that the SWMP for the construction site is complete (see Part I.C. below); and 9) The signature of the applicant, signed in accordance with Part I.F.1 of this permit. 5. Permit Certification Procedures If this general permit is appropriate for the applicant's operation, then a certification will be developed and the applicant will be authorized to discharge stormwater under this general permit. a) Request for Additional Information: The Division shall have up to ten calendar days after receipt of the above information to request additional data and/or deny the authorization for any particular discharge. Upon receipt of additional information, the Division shall have an additional ten calendar days to issue or deny authorization for the particular discharge. (Notification of denial shall be by letter, in cases where coverage under an alternate general permit or an individual permit is required, instead of coverage under this permit.) PART I Permit - Page 5 Permit No. COR-030000 A. COVERAGE UNDER THIS PERMIT (cont.) b) Automatic Coverage: If the applicant does not receive a request for additional information or a notification of denial from the Division dated within ten calendar days of receipt of the application by the Division, authorization to discharge in accordance with the conditions of this permit shall be deemed granted. c) Individual Permit Required: If, after evaluation of the application (or additional information, such as the SWMP), it is found that this general permit is not appropriate for the operation, then the application will be processed as one for an individual permit. The applicant will be notified of the Division's decision to deny certification under this general permit. For an individual permit, additional information may be requested, and 180 days may be required to process the application and issue the permit. At the Division's discretion, temporary coverage under this general permit may be allowed until the individual permit goes into effect. d) General vs. Individual Permit Coverage: Any permittee authorized by this permit may request to be excluded from the coverage of this permit by applying for an individual CDPS permit. The permittee shall submit an individual application, with reasons supporting the request, to the Division at least 180 days prior to any discharge. e) Local Agency Authority: This permit does not pre-empt or supersede the authority of local agencies to prohibit, restrict, or control discharges of stormwater to storm drain systems or other water courses within their jurisdiction. 6. Inactivation Notice When a site has been finally stabilized in accordance with the SWMP, the permittee must submit an Inactivation Notice form that is signed in accordance with Part I.F. 1 . of this permit. The Inactivation Notice form is available from the Division and includes: a) Permit certification number; b) The permittee's name, address, telephone number; c) Name, location, and county for the construction site for which the inactivation notice is being submitted; and d) Certification that the site has been finally stabilized, and a description of the final stabilization method(s). 7. Transfer of Permit When responsibility for stormwater discharges at a construction site changes from one entity to another, the permittee shall submit a completed Notice of Transfer and Acceptance of Terms form that is signed in accordance with Part I.F. 1 . of this permit. The Notice of Transfer form is available from the Division and includes: a) Permit certification number; b) Name, location, and county for the construction site for which the Notice of Transfer is being submitted; c) Identifying information for the new permittee; d) Identifying information for the current permittee; and e) Effective date of transfer. If the new responsible party will not complete the transfer form, the permit may be inactivated upon written request to the Division and completion of the Inactivation Notice if the permittee has no legal responsibility, through ownership or contract, for the construction activities at the site. In this case, the new owner or operator would be required to obtain permit coverage separately. 8. Reassignment of Permit When a permittee no longer has control of a specific portion of a permitted site, and wishes to transfer coverage of that portion of the site to a second party, the permittee shall submit a completed Notice of Reassignment of Permit Coverage form that is signed in accordance with Part I.F. 1 . of this permit. The Notice of Reassignment of Permit Coverage form is available from the Division and includes: a) Current permit certification number; b) Identifying information and certification as required by Part 1.A.4.b for the new permittee; c) Identifying information for the current permittee, revised site information and certification for reassignment; and d) Effective date of reassignment. PART I Permit - Page 6 Permit No. COR-030000 A. COVERAGE UNDER THIS PERMIT (cont.) If the new responsible party will not complete the reassignment form, the applicable portion of the permitted site may be removed from permit coverage upon written request to the Division if the permittee has no legal responsibility, through ownership or contract, for the construction activities at the portion of the site. In this case, the new owner or operator would be required to obtain permit coverage separately. 9. Sale of Residence to Homeowners For residential construction only, when a residential lot has been conveyed to a homeowner and all criteria in paragraphs a through e, below, are met, coverage under this permit is no longer required and the conveyed lot may be removed from coverage under the permittee's certification. At such time, the permittee is no longer responsible for meeting the terms and conditions of this permit for the conveyed lot, including the requirement to transfer or reassign permit coverage. The permittee remains responsible for inactivation of the original certification. a) The lot has been sold to the homeowner(s) for private residential use; b) the lot is less than one acre of disturbed area; c) all construction activity conducted by the permittee on the lot is completed; d) a certificate of occupancy (or equivalent) has been awarded to the home owner; and e) the SWMP has been amended to indicate the lot is no longer covered by permit. Lots not meeting all of the above criteria require continued permit coverage. However, this permit coverage may be transferred (Part I.A.7, above) or reassigned (Part I.A.8, above) to a new owner or operator. 10. Permit Expiration Date Authorization to discharge under this general permit shall expire on June 30, 2012. The Division must evaluate and reissue this general permit at least once every five years and must recertify the permittee's authority to discharge under the general permit at such time. Therefore, a permittee desiring continued coverage under the general permit must reapply by March 31, 2012. The Division will initiate the renewal process; however, it is ultimately the permittee's responsibility to ensure that the renewal is submitted. The Division will determine if the permittee may continue to operate under the terms of the general permit. An individual permit may be required for any facility not reauthorized to discharge under the reissued general permit. 11 . Individual Permit Criteria Various criteria can be used in evaluating whether or not an individual (or alternate general) permit is required instead of this general permit. This information may come from the application, SWMP, or additional information as requested by the Division, and includes, but is not limited to, the following: a) the quality of the receiving waters (i.e., the presence of downstream drinking water intakes or a high quality fishery, or for preservation of high quality water); b) the size of the construction site; c) evidence of noncompliance under a previous permit for the operation; d) the use of chemicals within the stormwater system; or e) discharges of pollutants of concern to waters for which there is an established Total Maximum Daily Load (TMDL). In addition, an individual permit may be required when the Division has shown or has reason to suspect that the stormwater discharge may contribute to a violation of a water quality standard. B. STORMWATER MANAGEMENT PLAN (SWMP) - GENERAL REQUIREMENTS 1 . A SWMP shall be developed for each facility covered by this permit. The SWMP shall be prepared in accordance with good engineering, hydrologic and pollution control practices. (The SWMP need not be prepared by a registered engineer.) PART I Permit - Page 7 Permit No. COR-030000 B. STORMWATER MANAGEMENT PLAN (SWMP) — GENERAL REQUIREMENTS (cont.) 2. The SWMP shall: a) Identify all potential sources of pollution which may reasonably be expected to affect the quality of stormwater discharges associated with construction activity from the facility; b) Describe the practices to be used to reduce the pollutants in stormwater discharges associated with construction activity at the facility; and ensure the practices are selected and described in accordance with good engineering practices, including the installation, implementation and maintenance requirements; and c) Be properly prepared, and updated in accordance with Part I.D.5.c, to ensure compliance with the terms and conditions of this permit. 3. Facilities must implement the provisions of the SWMP as written and updated, from commencement of construction activity until final stabilization is complete, as a condition of this permit. The Division reserves the right to review the SWMP, and to require the permittee to develop and implement additional measures to prevent and control pollution as needed. 4. The SWMP may reflect requirements for Spill Prevention Control and Countermeasure (SPCC) plans under section 311 of the CWA, or Best Management Practices (BMPs) Programs otherwise required by a separate CDPS permit, and may incorporate any part of such plans into the SWMP by reference, provided that the relevant sections of such plans are available as part of the SWMP consistent with Part I.D.5.b. 5. For any sites with permit coverage before June 30, 2007, the permittee's SMWP must meet the new SWMP requirements as summarized in Section 11.1 of the rationale. Any needed changes must be made by October 1, 2007. C. STORMWATER MANAGEMENT PLAN (SWMP) — CONTENTS The SWMP shall include the following items, at a minimum. 1 . Site Description. The SWMP shall clearly describe the construction activity, to include: a) The nature of the construction activity at the site. b) The proposed sequence for major activities. c) Estimates of the total area of the site, and the area and location expected to be disturbed by clearing, excavation, grading, or other construction activities. d) A summary of any existing data used in the development of the site construction plans or SWMP that describe the soil or existing potential for soil erosion. e) A description of the existing vegetation at the site and an estimate of the percent vegetative ground cover. f) The location and description of all potential pollution sources, including ground surface disturbing activities (see Part I.A.2.b), vehicle fueling, storage of fertilizers or chemicals, etc. g) The location and description of any anticipated allowable sources of non-stormwater discharge at the site, e.g., uncontaminated springs, landscape irrigation return flow, construction dewatering, and concrete washout. h) The name of the receiving water(s) and the size, type and location of any outfall(s). If the stormwater discharge is to a municipal separate storm sewer system, the name of that system, the location of the storm sewer discharge, and the ultimate receiving water(s). 2. Site Map. The SWMP shall include a legible site map(s), showing the entire site, identifying: a) construction site boundaries; b) all areas of ground surface disturbance; c) areas of cut and fill; d) areas used for storage of building materials, equipment, soil, or waste; e) locations of dedicated asphalt or concrete batch plants; 0 locations of all structural BMPs; g) locations of non-structural BMPs as applicable; and h) locations of springs, streams, wetlands and other surface waters. PART I Permit - Page 8 Permit No. COR-030000 C. STORMWATER MANAGEMENT PLAN (SWMP) — CONTENTS (cont.) 3. Stormwater Management Controls. The SWMP must include a description of all stormwater management controls that will be implemented as part of the construction activity to control pollutants in stormwater discharges. The appropriateness and priorities of stormwater management controls in the SWMP shall reflect the potential pollutant sources identified at the facility. The description of stormwater management controls shall address the following components, at a minimum: a) SWMP Administrator - The SWMP shall identify a specific individual(s), position or title who is responsible for developing, implementing, maintaining, and revising the SWMP. The activities and responsibilities of the administrator shall address all aspects of the facility's SWMP. b) Identification of Potential Pollutant Sources - All potential pollutant sources, including materials and activities, at a site must be evaluated for the potential to contribute pollutants to stormwater discharges. The SWMP shall identify and describe those sources determined to have the potential to contribute pollutants to stormwater discharges, and the sources must be controlled through BMP selection and implementation, as required in paragraph (c), below. At a minimum, each of the following sources and activities shall be evaluated for the potential to contribute pollutants to stormwater discharges, and identified in the SWMP if found to have such potential: 1) all disturbed and stored soils; 2) vehicle tracking of sediments; 3) management of contaminated soils; 4) loading and unloading operations; 5) outdoor storage activities (building materials, fertilizers, chemicals, etc.); 6) vehicle and equipment maintenance and fueling; 7) significant dust or particulate generating processes; 8) routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, oils, etc.; 9) on-site waste management practices (waste piles, liquid wastes, dumpsters, etc.); 10) concrete truck/equipment washing, including the concrete truck chute and associated fixtures and equipment; 11) dedicated asphalt and concrete batch plants; 12) non-industrial waste sources such as worker trash and portable toilets; and 13) other areas or procedures where potential spills can occur. c) Best Management Practices (BMPs) for Stormwater Pollution Prevention - The SWMP shall identify and describe appropriate BMPs, including, but not limited to, those required by paragraphs 1 through 8 below, that will be implemented at the facility to reduce the potential of the sources identified in Part I.C.3.b to contribute pollutants to stormwater discharges. The SWMP shall clearly describe the installation and implementation specifications for each BMP identified in the SWMP to ensure proper implementation, operation and maintenance of the BMP. 1) Structural Practices for Erosion and Sediment Control. The SWMP shall clearly describe and locate all structural practices implemented at the site to minimize erosion and sediment transport. Practices may include, but are not limited to: straw bales, wattles/sediment control logs, silt fences, earth dikes, drainage swales, sediment traps, subsurface drains, pipe slope drains, inlet protection, outlet protection, gabions, and temporary or permanent sediment basins. 2) Non-Structural Practices for Erosion and Sediment Control. The SWMP shall clearly describe and locate, as applicable, all non-structural practices implemented at the site to minimize erosion and sediment transport. Description must include interim and permanent stabilization practices, and site-specific scheduling for implementation of the practices. The SWMP should include practices to ensure that existing vegetation is preserved where possible. Non-structural practices may include, but are not limited to: temporary vegetation, permanent vegetation, mulching, geotextiles, sod stabilization, slope roughening, vegetative buffer strips, protection of trees, and preservation of mature vegetation. PART I Permit - Page 9 Permit No. COR-030000 C. STORMWATER MANAGEMENT PLAN (SWMP) — CONTENTS (cont.) 3) Phased BMP Implementation. The SWMP shall clearly describe the relationship between the phases of construction, and the implementation and maintenance of both structural and non-structural stormwater management controls. The SWMP must identify the stormwater management controls to be implemented during the project phases, which can include, but are not limited to, clearing and grubbing; road construction; utility and infrastructure installation; vertical construction; final grading; and final stabilization. 4) Materials Handling and Spill Prevention. The SWMP shall clearly describe and locate all practices implemented at the site to minimize impacts from procedures or significant materials (see definitions at Part I.E.) that could contribute pollutants to runoff. Such procedures or significant materials could include: exposed storage of building materials; paints and solvents; fertilizers or chemicals; waste material; and equipment maintenance or fueling procedures. Areas or procedures where potential spills can occur must have spill prevention and response procedures identified in the SWMP. 5) Dedicated Concrete or Asphalt Batch Plants. The SWMP shall clearly describe and locate all practices implemented at the site to control stormwater pollution from dedicated concrete batch plants or dedicated asphalt batch plants covered by this certification. 6) Vehicle Tracking Control. The SWMP shall clearly describe and locate all practices implemented at the site to control potential sediment discharges from vehicle tracking. Practices must be implemented for all areas of potential vehicle tracking, and can include: minimizing site access; street sweeping or scraping; tracking pads; graveled parking areas; requiring that vehicles stay on paved areas on-site; wash racks; contractor education; and/or sediment control BMPs, etc. 7) Waste Management and Disposal, Including Concrete Washout. i) The SWMP shall clearly describe and locate the practices implemented at the site to control stormwater pollution from all construction site wastes (liquid and solid), including concrete washout activities. ii) The practices used for concrete washout must ensure that these activities do not result in the contribution of pollutants associated with the washing activity to stormwater runoff. iii) Part I.D.3.c of the permit authorizes the conditional discharge of concrete washout water to the ground. The SWMP shall clearly describe and locate the practices to be used that will ensure that no washout water from concrete washout activities is discharged from the site as surface runoff or to surface waters. 8) Groundwater and Stormwater Dewatering. i) The SWMP shall clearly describe and locate the practices implemented at the site to control stormwater pollution from the dewatering of groundwater or stormwater from excavations, wells, etc. ii) Part I.D.3.d of the permit authorizes the conditional discharge of construction dewatering to the ground. For any construction dewatering of groundwater not authorized under a separate CDPS discharge permit, the SWMP shall clearly describe and locate the practices to be used that will ensure that no groundwater from construction dewatering is discharged from the site as surface runoff or to surface waters. 4. Final Stabilization and Long-term Stormwater Management a) The SWMP shall clearly describe the practices used to achieve final stabilization of all disturbed areas at the site, and any planned practices to control pollutants in stormwater discharges that will occur after construction operations have been completed at the site. b) Final stabilization practices for obtaining a vegetative cover should include, as appropriate: seed mix selection and application methods; soil preparation and amendments; soil stabilization practices (e.g., crimped straw, hydro mulch or rolled erosion control products); and appropriate sediment control BMPs as needed until final stabilization is achieved; etc. PART I Permit - Page 10 Permit No. COR-030000 C. STORMWATER MANAGEMENT PLAN (SWMP) — CONTENTS (cont.) c) Final stabilization is reached when all ground surface disturbing activities at the site have been completed, and uniform vegetative cover has been established with an individual plant density of at least 70 percent of pre- disturbance levels, or equivalent permanent, physical erosion reduction methods have been employed. The Division may, after consultation with the permittee and upon good cause, amend the final stabilization criteria in this section for specific operations. 5. Inspection and Maintenance Part I.D.6 of the permit includes requirements for site inspections. Part I.D.7 of the permit includes requirements for BMP maintenance. The SWMP shall clearly describe the inspection and maintenance procedures implemented at the site to maintain all erosion and sediment control practices and other protective practices identified in the SWMP, in good and effective operating condition. D. TERMS AND CONDITIONS 1 . General Limitations The following limitations shall apply to all discharges covered by this permit: a) Stormwater discharges from construction activities shall not cause, have the reasonable potential to cause, or measurably contribute to an exceedance of any water quality standard, including narrative standards for water quality. b) Concrete washout water shall not be discharged to state surface waters or to storm sewer systems. On-site permanent disposal of concrete washout waste is not authorized by this permit. Discharge to the ground of concrete washout waste that will subsequently be disposed of off-site is authorized by this permit. See Part I.D.3.c of the permit. c) Bulk storage structures for petroleum products and any other chemicals shall have secondary containment or equivalent adequate protection so as to contain all spills and prevent any spilled material from entering State waters. d) No chemicals are to be added to the discharge unless permission for the use of a specific chemical is granted by the Division. In granting the use of such chemicals, special conditions and monitoring may be addressed by separate correspondence. e) The Division reserves the right to require sampling and testing, on a case-by-case basis, in the event that there is reason to suspect that compliance with the SWMP is a problem, or to measure the effectiveness of the BMPs in removing pollutants in the effluent. Such monitoring may include Whole Effluent Toxicity testing. 0 All site wastes must be properly managed to prevent potential pollution of State waters. This permit does not authorize on-site waste disposal. g) All dischargers must comply with the lawful requirements of federal agencies, municipalities, counties, drainage districts and other local agencies regarding any discharges of stormwater to storm drain systems or other water courses under their jurisdiction, including applicable requirements in municipal stormwater management programs developed to comply with CDPS permits. Dischargers must comply with local stormwater management requirements, policies or guidelines including erosion and sediment control. 2. BMP Implementation and Design Standards Facilities must select, install, implement, and maintain appropriate BMPs, following good engineering, hydrologic and pollution control practices. BMPs implemented at the site must be adequately designed to provide control for all potential pollutant sources associated with construction activity to prevent pollution or degradation of State waters. PART I Permit - Page 11 Permit No. COR-030000 D. TERMS AND CONDITIONS (cont.) 3. Prohibition of Non-Stormwater Discharges a) Except as provided in paragraphs b, c, and d below, all discharges covered by this permit shall be composed entirely of stormwater associated with construction activity. Discharges of material other than stormwater must be addressed in a separate CDPS permit issued for that discharge. b) Discharges from the following sources that are combined with stormwater discharges associated with construction activity may be authorized by this permit, provided that the non-stormwater component of the discharge is identified in the SWMP (see Part I.C. l .g of this permit): - emergency fire fighting activities - landscape irrigation return flow - uncontaminated springs c) Discharges to the ground of concrete washout water from washing of tools and concrete mixer chutes may be authorized by this permit, provided that: 1) the source is identified in the SWMP; 2) BMPs are included in the SWMP in accordance with Part I.C.3(c)(7) and to prevent pollution of groundwater in violation of Part I.D.1 .a; and 3) these discharges do not leave the site as surface runoff or to surface waters d) Discharges to the ground of water from construction dewatering activities may be authorized by this permit, provided that: 1) the source is groundwater and/or groundwater combined with stormwater that does not contain pollutants in concentrations exceeding the State groundwater standards in Regulations 5 CCR 1002-41 and 42; 2) the source is identified in the SWMP; 3) BMPs are included in the SWMP, as required by Part I.C.3(c)(8); and 4) these discharges do not leave the site as surface runoff or to surface waters. Discharges to the ground from construction dewatering activities that do not meet the above criteria must be covered under a separate CDPS discharge permit. Contaminated groundwater requiring coverage under a separate CDPS discharge permit may include groundwater contaminated with pollutants from a landfill, mining activity, industrial pollutant plume, underground storage tank, or other source. 4. Releases in Excess of Reportable Quantities This permit does not relieve the permittee of the reporting requirements of 40 CFR 110, 40 CFR 117 or 40 CFR 302. Any discharge of hazardous material must be handled in accordance with the Division's Noncompliance Notification Requirements (see Part II.A.3 of the permit). 5. SWMP Requirements a) SWMP Preparation and Implementation: The SWMP shall be prepared prior to applying for coverage under the general permit, and certification of its completion submitted with the application. The SWMP shall be implemented prior to commencement of construction activities. The plan shall be updated as appropriate (see paragraph c, below), below). SWMP provisions shall be implemented until expiration or inactivation of permit coverage. b) SWMP Retention Requirements: A copy of the SWMP must be retained on site unless another location, specified by the permittee, is approved by the Division. c) SWMP Review/Changes: The permittee shall amend the SWMP: 1) when there is a change in design, construction, operation, or maintenance of the site, which would require the implementation of new or revised BMPs; or 2) if the SWMP proves to be ineffective in achieving the general objectives of controlling pollutants in stormwater discharges associated with construction activity; or PART I Permit - Page 12 Permit No. COR-030000 D. TERMS AND CONDITIONS (cont.) 3) when BMPs are no longer necessary and are removed. SWMP changes shall be made prior to changes in the site conditions, except as allowed for in paragraph d, below. SWMP revisions may include, but are not limited to: potential pollutant source identification; selection of appropriate BMPs for site conditions; BMP maintenance procedures; and interim and final stabilization practices. The SWMP changes may include a schedule for further BMP design and implementation, provided that, if any interim BMPs are needed to comply with the permit, they are also included in the SWMP and implemented during the interim period. d) Responsive SWMP Changes: SWMP changes addressing BMP installation and/or implementation are often required to be made in response to changing conditions, or when current BMPs are determined ineffective. The majority of SWMP revisions to address these changes can be made immediately with quick in-the-field revisions to the SWMP. In the less common scenario where more complex development of materials to modify the SWMP is necessary, SWMP revisions shall be made in accordance with the following requirements: 1) the SWMP shall be revised as soon as practicable, but in no case more than 72 hours after the change(s) in BMP installation and/or implementation occur at the site, and 2) a notation must be included in the SWMP prior to the site change(s) that includes the time and date of the change(s) in the field, an identification of the BMP(s) removed or added, and the location(s) of those BMP(s). 6. Inspections Site inspections must be conducted in accordance with the following requirements and minimum schedules. The required minimum inspection schedules do not reduce or eliminate the permittee's responsibility to implement and maintain BMPs in good and effective operational condition, and in accordance with the SWMP, which could require more frequent inspections. a) Minimum Inspection Schedule: The permittee shall, at a minimum, make a thorough inspection, in accordance with the requirements in I.D.6.b below, at least once every 14 calendar days. Also, post-storm event inspections must be conducted within 24 hours after the end of any precipitation or snowmelt event that causes surface erosion. Provided the timing is appropriate, the post-storm inspections may be used to fulfill the 14-day routine inspection requirement. A more frequent inspection schedule than the minimum inspections described may be necessary, to ensure that BMPs continue to operate as needed to comply with the permit. The following conditional modifications to this Minimum Inspection Schedule are allowed: 1) Post-Storm Event Inspections at Temporarily Idle Sites — If no construction activities will occur following a storm event, post-storm event inspections shall be conducted prior to re-commencing construction activities, but no later than 72 hours following the storm event. The occurrence of any such delayed inspection must be documented in the inspection record. Routine inspections still must be conducted at least every 14 calendar days. 2) Inspections at Completed Sites/Areas - For sites or portions of sites that meet the following criteria, but final stabilization has not been achieved due to a vegetative cover that has not become established, the permittee shall make a thorough inspection of their stormwater management system at least once every month, and post- storm event inspections are not required. This reduced inspection schedule is only allowed if: i) all construction activities that will result in surface ground disturbance are completed; ii) all activities required for final stabilization, in accordance with the SWMP, have been completed, with the exception of the application of seed that has not occurred due to seasonal conditions or the necessity for additional seed application to augment previous efforts; and iii) the SWMP has been amended to indicate those areas that will be inspected in accordance with the reduced schedule allowed for in this paragraph. PART I Permit - Page 13 Permit No. COR-030000 D. TERMS AND CONDITIONS (cont.) 3) Winter Conditions Inspections Exclusion — Inspections are not required at sites where construction activities are temporarily halted, snow cover exists over the entire site for an extended period, and melting conditions posing a risk of surface erosion do not exist. This exception is applicable only during the period where melting conditions do not exist, and applies to the routine 14-day and monthly inspections, as well as the post-storm- event inspections. The following information must be documented in the inspection record for use of this exclusion: dates when snow cover occurred, date when construction activities ceased, and date melting conditions began. Inspections, as described above, are required at all other times. When site conditions make the schedule required in this section impractical, the permittee may petition the Division to grant an alternate inspection schedule. b) Inspection Requirements 1) Inspection Scope - The construction site perimeter, all disturbed areas, material and/or waste storage areas that are exposed to precipitation, discharge locations, and locations where vehicles access the site shall be inspected for evidence of, or the potential for, pollutants leaving the construction site boundaries, entering the stormwater drainage system, or discharging to state waters. All erosion and sediment control practices identified in the SWMP shall be evaluated to ensure that they are maintained and operating correctly. 2) Inspection Report/Records - The permittee shall keep a record of inspections. Inspection reports must identify any incidents of non-compliance with the terms and conditions of this permit. Inspection records must be retained for three years from expiration or inactivation of permit coverage. At a minimum, the inspection report must include: i) The inspection date; ii) Name(s) and title(s) of personnel making the inspection; iii) Location(s) of discharges of sediment or other pollutants from the site; iv) Location(s) of BMPs that need to be maintained; v) Location(s) of BMPs that failed to operate as designed or proved inadequate for a particular location; vi) Location(s) where additional BMPs are needed that were not in place at the time of inspection; vii) Deviations from the minimum inspection schedule as provided in Part I.D.6.a above; vii) Description of corrective action for items iii, iv, v, and vi, above, dates corrective action(s) taken, and measures taken to prevent future violations, including requisite changes to the SWMP, as necessary; and viii) After adequate corrective action(s) has been taken, or where a report does not identify any incidents requiring corrective action, the report shall contain a signed statement indicating the site is in compliance with the permit to the best of the signer's knowledge and belief c) Required Actions Following Site Inspections - Where site inspections note the need for BMP maintenance activities, BMPs must be maintained in accordance with the SWMP and Part I.D.7 of the permit. Repair, replacement, or installation of new BMPs determined necessary during site inspections to address ineffective or inadequate BMPs must be conducted in accordance with Part I.D.8 of the permit. SWMP updates required as a result of deficiencies in the SWMP noted during site inspections shall be made in accordance with Part I.D.5.c of the permit. 7. BMP Maintenance All erosion and sediment control practices and other protective measures identified in the SWMP must be maintained in effective operating condition. Proper selection and installation of BMPs and implementation of comprehensive Inspection and Maintenance procedures, in accordance with the SWMP, should be adequate to meet this condition. BMPs that are not adequately maintained in accordance with good engineering, hydrologic and pollution control practices, including removal of collected sediment outside the acceptable tolerances of the BMPs, are considered to be no longer operating effectively and must be addressed in accordance with Part I.D.8, below. A specific timeline for implementing maintenance procedures is not included in this permit because BMP maintenance is expected to be proactive, not responsive. Observations resulting in BMP maintenance activities can be made during a site inspection, or during general observations of site conditions. PART I Permit - Page 14 Permit No. COR-030000 D. TERMS AND CONDITIONS (cont.) 8. Replacement and Failed BMPs Adequate site assessment must be performed as part of comprehensive Inspection and. Maintenance procedures, to assess the adequacy of BMPs at the site, and the necessity of changes to those BMPs to ensure continued effective performance. Where site assessment results in the determination that new or replacement BMPs are necessary, the BMPs must be installed to ensure on-going implementation of BMPs as per Part I.D.2. Where BMPs have failed, resulting in noncompliance with Part I.D.2, they must be addressed as soon as possible, immediately in most cases, to minimize the discharge of pollutants. When new BMPs are installed or BMPs are replaced, the SWMP must be updated in accordance with Part I.D.5(c). 9. Reporting No scheduled reporting requirements are included in this permit; however, the Division reserves the right to request that a copy of the inspection reports be submitted. 10. SWMP Availability A copy of the SWMP shall be provided upon request to the Division, EPA, or any local agency in charge of approving sediment and erosion plans, grading plans or stormwater management plans, and within the time frame specified in the request. If the SWMP is required to be submitted to any of these entities, it must include a signed certification in accordance with Part I.F. 1 of the permit, certifying that the SWMP is complete and meets all permit requirements. All SWMPs required under this permit are considered reports that shall be available to the public under Section 308(b) of the CWA and Section 61 .5(4) of the Colorado Discharge Permit System Regulations. The permittee shall make plans available to members of the public upon request. However, the permittee may claim any portion of a SWMP as confidential in accordance with 40 CFR Part 2. 11 . Total Maximum Daily Load (TMDL) If a TMDL has been approved for any waterbody into which the permittee discharges, and stormwater discharges associated with construction activity have been assigned a pollutant-specific Wasteload Allocation (WLA) under the TMDL, the Division will either: a) Ensure that the WLA is being implemented properly through alternative local requirements, such as by a municipal stormwater permit; or b) Notify the permittee of the WLA, and amend the penmittee's certification to add specific BMPs and/or other requirements, as appropriate. The permittee may be required to do the following: 1) Under the permittee's SWMP, implement specific management practices based on requirements of the WLA, and evaluate whether the requirements are being met through implementation of existing stormwater BMPs or if additional BMPs are necessary. Document the calculations or other evidence that show that the requirements are expected to be met; and 2) If the evaluation shows that additional or modified BMPs are necessary, describe the type and schedule for the BMP additions/revisions. Discharge monitoring may also be required. The permittee may maintain coverage under the general permit provided they comply with the applicable requirements outlined above. The Division reserves the right to require individual or alternate general permit coverage. PART I Permit - Page 15 Permit No. COR-030000 E. ADDITIONAL DEFINITIONS For the purposes of this permit: 1 . Best Management Practices (BMPs): schedules of activities, prohibitions of practices, maintenance procedures, and other management practices to prevent or reduce the pollution of waters of the State. BMPs also include treatment requirements, operating procedures, pollution prevention, and practices to control site runoff, spillage or leaks, waste disposal, or drainage from material storage. 2. Dedicated asphalt plants and concrete plants: portable asphalt plants and concrete plants that are located on or adjacent to a construction site and that provide materials only to that specific construction site. 3. Final stabilization: when all ground surface disturbing activities at the site have been completed, and uniform vegetative cover has been established with an individual plant density of at least 70 percent of pre-disturbance levels, or equivalent permanent, physical erosion reduction methods have been employed. For purposes of this permit, establishment of a vegetative cover capable of providing erosion control equivalent to pre-existing conditions at the site will be considered final stabilization. 4. Municipal separate storm sewer system: a conveyance or system of conveyances (including: roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains), owned or operated by a State, city, town, county, district, or other public body (created by state law), having jurisdiction over disposal of sewage, industrial waste, stormwater, or other wastes; designed or used for collecting or conveying stormwater. 5. Operator: the entity that has day-to-day supervision and control of activities occurring at the construction site. This can be the owner, the developer, the general contractor or the agent of one of these parties, in some circumstances. It is anticipated that at different phases of a construction project, different types of parties may satisfy the definition of 'operator' and that the permit may be transferred as the roles change. 6. Outfall: a point source at the point where stormwater leaves the construction site and discharges to a receiving water or a stormwater collection system. 7. Part of a larger common plan of development or sale: a contiguous area where multiple separate and distinct construction activities may be taking place at different times on different schedules. 8. Point source: any discernible, confined and discrete conveyance from which pollutants are or may be discharged. Point source discharges of stormwater result from structures which increase the imperviousness of the ground which acts to collect runoff, with runoff being conveyed along the resulting drainage or grading pattern. 9. Pollutant: dredged spoil, dirt, slurry, solid waste, incinerator residue, sewage, sewage sludge, garbage, trash, chemical waste, biological nutrient, biological material, radioactive material, heat, wrecked or discarded equipment, rock, sand, or any industrial, municipal or agricultural waste. 10. Process water: any water which, during manufacturing or processing, comes into contact with or results from the production of any raw material, intermediate product, finished product, by product or waste product. This definition includes mine drainage. 11 . Receiving Water: any classified stream segment (including tributaries) in the State of Colorado into which stormwater related to construction activities discharges. This definition includes all water courses, even if they are usually dry, such as borrow ditches, arroyos, and other unnamed waterways. 12. Significant Materials include, but are not limited to: raw materials; fuels; materials such as solvents, detergents, and plastic pellets; finished materials such as metallic products; raw materials used in food processing or production; hazardous substances designated under section 101 (14) of CERCLA; any chemical the facility is required to report pursuant to section 313 of title III of SARA; fertilizers; pesticides; and waste products such as ashes, slag and sludge that have the potential to be released with stormwater discharge. 13. Stormwater: precipitation-induced surface runoff. PART I Permit - Page 16 Permit No. COR-030000 F. GENERAL REQUIREMENTS 1 . Signatory Requirements a) All reports required for submittal shall be signed and certified for accuracy by the permittee in accordance with the following criteria: 1 ) In the case of corporations, by a principal executive officer of at least the level of vice-president or his or her duly authorized representative, if such representative is responsible for the overall operation of the facility from which the discharge described in the form originates; 2) In the case of a partnership, by a general partner; 3) In the case of a sole proprietorship, by the proprietor; 4) In the case of a municipal, state, or other public facility, by either a principal executive officer, ranking elected official, or other duly authorized employee, if such representative is responsible for the overall operation of the facility from which the discharge described in the form originates. b) Changes to authorization. If an authorization under paragraph a) of this section is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of paragraph a) of this section must be submitted to the Division, prior to or together with any reports, information, or applications to be signed by an authorized representative. c) Certification. Any person signing a document under paragraph a) of this section shall make the following certification: "I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations." 2. Retention of Records a) The permittee shall retain copies of the SWMP and all reports required by this permit and records of all data used to complete the application to be covered by this permit, for three years after expiration or inactivation of permit coverage. b) The permittee shall retain a copy of the SWMP required by this permit at the construction site from the date of project initiation to the date of expiration or inactivation of permit coverage, unless another location, specified by the permittee, is approved by the Division. 3. Monitoring The Division reserves the right to require sampling and testing, on a case-by-case basis (see Part I.D. 1 .e), for example to implement the provisions of a TMDL (see Part I.D. 11 of the permit). Reporting procedures for any monitoring data collected will be included in the notification by the Division of monitoring requirements. If monitoring is required, the following definitions apply: a) The thirty (30) day average shall be determined by the arithmetic mean of all samples collected during a thirty (30) consecutive-day period. b) A grab sample, for monitoring requirements, is a single "dip and take" sample. PART II A. MANAGEMENT REQUIREMENTS 1 . Amending a Permit Certification The permittee shall inform the Division (Permits Section) in writing of changes to the information provided in the permit application, including the legal contact, the project legal description or map originally submitted with the application, or the planned total disturbed acreage. The permittee shall furnish the Division with any plans and specifications which the Division deems reasonably necessary to evaluate the effect on the discharge and receiving stream. If applicable, this notification may be accomplished through submittal of an application for a CDPS process water permit authorizing the discharge. The SWMP shall be updated and implemented prior to the changes (see Part I.D.5.c). Any discharge to the waters of the State from a point source other than specifically authorized by this permit or a different CDPS permit is prohibited. 2. Special Notifications - Definitions a) Spill: An unintentional release of solid or liquid material which may cause pollution of state waters. b) Upset: An exceptional incident in which there is unintentional and temporary noncompliance with permit discharge limitations because of factors beyond the reasonable control of the permittee. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventative maintenance, or careless or improper operation. 3. Noncompliance Notification a) The permittee shall report the following instances of noncompliance: 1 ) Any noncompliance which may endanger health or the environment; 2) Any spill or discharge of hazardous substances or oil which may cause pollution of the waters of the state. 3) Any discharge of stormwater which may cause an exceedance of a water quality standard. b) For all instances of noncompliance based on environmental hazards and chemical spills and releases, all needed information must be provided orally to the Colorado Department of Public Health and Environment spill reporting line (24-hour number for environmental hazards and chemical spills and releases: 1-877-518-5608) within 24 hours from the time the permittee becomes aware of the circumstances. For all other instances of noncompliance as defined in this section, all needed information must be provided orally to the Water Quality Control Division within 24 hours from the time the permittee becomes aware of the circumstances. For all instances of noncompliance identified here, a written submission shall also be provided within 5 calendar days of the time the permittee becomes aware of the circumstances. The written submission shall contain a description of: 1) The noncompliance and its cause; 2) The period of noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; 3) Steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. A. MANAGEMENT REQUIREMENTS (cont.) 4. Submission of Incorrect or Incomplete Information Where the permittee failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or report to the Division, or relevant new information becomes available, the permittee shall promptly submit the relevant application information which was not submitted or any additional information needed to correct any erroneous information previously submitted. 5. Bypass a) A bypass, which causes effluent limitations (i.e., requirements to implement BMPs in accordance with Parts I.B.3 and I.D.2 of the permit) to be exceeded is prohibited, and the Division may take enforcement action against a permittee for such a bypass, unless: 1) Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage; 2) There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities (e.g., alternative BMPs), retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if the permittee could have installed adequate backup equipment (e.g., implemented additional BMPs) to prevent a bypass which occurred during normal periods of equipment downtime or preventative maintenance; and 3) The permittee submitted notices as required in "Non-Compliance Notification," Part II.A.3. 6. Upsets a) Effect of an Upset: An upset constitutes an affirmative defense to an action brought for noncompliance with permit limitations and requirements if the requirements of paragraph b of this section are met. (No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review.) b) Conditions Necessary for a Demonstration of Upset: A permittee who wishes to establish the affirmative defense of upset shall demonstrate through properly signed contemporaneous operating logs, or other relevant evidence that: 1) An upset occurred and that the permittee can identify the specific cause(s) of the upset; 2) The permitted facility was at the time being properly operated; 3) The permittee submitted notice of the upset as required in Part II.A.3. of this permit (24-hour notice); and 4) The permittee complied with any remedial measures required under 40 CFR Section 122.41 (d) of the federal regulations or Section 61 .8(3)(h) of the Colorado Discharge Permit System Regulations. c) Burden of Proof: In any enforcement proceeding the permittee seeking to establish the occurrence of an upset has the burden of proof 7. Removed Substances Solids, sludges, or other pollutants removed in the course of treatment or control of discharges shall be properly disposed of in a manner such as to prevent any pollutant from such materials from entering waters of the State. 8. Minimization of Adverse Impact The permittee shall take all reasonable steps to minimize any adverse impact to waters of the State resulting from noncompliance with any terms and conditions specified in this permit, including such accelerated or additional monitoring as necessary to determine the nature and impact of the noncomplying discharge. A. MANAGEMENT REQUIREMENTS (cont.) 9. Reduction, Loss, or Failure of Stormwater Controls The permittee has the duty to halt or reduce any activity if necessary to maintain compliance with the permit requirements. Upon reduction, loss, or failure of any stormwater controls, the permittee shall, to the extent necessary to maintain compliance with its permit, control production, or remove all pollutant sources from exposure to stormwater, or both, until the stormwater controls are restored or an alternative method of treatment/control is provided. It shall not be a defense for a permittee in an enforcement action that it would be necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this permit. 10. Proper Operation and Maintenance The permittee shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the permittee to achieve compliance with the conditions of this permit. Proper operation and maintenance includes effective performance, adequate funding, adequate operator staffing and training, and adequate laboratory and process controls, including appropriate quality assurance procedures. This provision requires the operation of back-up or auxiliary facilities or similar systems only when necessary to achieve compliance with the conditions of the permit. B. RESPONSIBILITIES 1 . Inspections and Right to Entry The permittee shall allow the Director of the State Water Quality Control Division, the EPA Regional Administrator, and/or their authorized representative(s), upon the presentation of credentials: a) To enter upon the permittee's premises where a regulated facility or activity is located or in which any records are required to be kept under the terms and conditions of this permit; b) At reasonable times to have access to and copy any records required to be kept under the terms and conditions of this permit and to inspect any monitoring equipment or monitoring method required in the permit; and c) To enter upon the permittee's premises to investigate, within reason, any actual, suspected, or potential source of water pollution, or any violation of the Colorado Water Quality Control Act. The investigation may include, but is not limited to, the following: sampling of any discharge and/or process waters, the taking of photographs, interviewing permittee staff on alleged violations and other matters related to the permit, and access to any and all facilities or areas within the permittee's premises that may have any effect on the discharge, permit, or any alleged violation. 2. Duty to Provide Information The permittee shall furnish to the Division, within the time frame specified by the Division, any information which the Division may request to determine whether cause exists for modifying, revoking and reissuing, or inactivating coverage under this permit, or to determine compliance with this permit. The permittee shall also furnish to the Division, upon request, copies of records required to be kept by this permit. 3. Transfer of Ownership or Control Certification under this permit may be transferred to a new permittee if: a) The current permittee notifies the Division in writing when the transfer is desired as outlined in Part I.A.7; and b) The notice includes a written agreement between the existing and new permittees containing a specific date for transfer of permit responsibility, coverage and liability between them; and c) The current permittee has met all fee requirements of the Colorado Discharge Permit System Regulations, Section 61 . 15. B. RESPONSIBILITIES (cont.) 4. Modification, Suspension, or Revocation of Permit By Division All permit modification, inactivation or revocation and reissuance actions shall be subject to the requirements of the Colorado Discharge Permit System Regulations, Sections 61 .5(2), 61 .5(3), 61 .7 and 61 . 15, 5 C.C.R. 1002-61, except for minor modifications. a) This permit, and/or certification under this permit, may be modified, suspended, or revoked in whole or in part during its term for reasons determined by the Division including, but not limited to, the following: 1 ) Violation of any terms or conditions of the permit; 2) Obtaining a permit by misrepresentation or failing to disclose any fact which is material to the granting or denial of a permit or to the establishment of terms or conditions of the permit; 3) Materially false or inaccurate statements or information in the application for the permit; 4) Promulgation of toxic effluent standards or prohibitions (including any schedule of compliance specified in such effluent standard or prohibition) which are established under Section 307 of the Clean Water Act, where such a toxic pollutant is present in the discharge and such standard or prohibition is more stringent than any limitation for such pollutant in this permit. b) This permit, and/or certification under this permit, may be modified in whole or in part due to a change in any condition that requires either a temporary or permanent reduction or elimination of the permitted discharge, such as: 1) Promulgation of Water Quality Standards applicable to waters affected by the permitted discharge; or 2) Effluent limitations or other requirements applicable pursuant to the State Act or federal requirements; or 3) Control regulations promulgated; or 4) Other available information indicates a potential for violation of adopted Water Quality Standards or stream classifications. c) This permit, or certification under this permit, may be modified in whole or in part to include new effluent limitations and other appropriate permit conditions where data submitted pursuant to Part I indicate that such effluent limitations and permit conditions are necessary to ensure compliance with applicable water quality standards and protection of classified uses. d) At the request of the permittee, the Division may modify or inactivate certification under this permit if the following conditions are met: 1) In the case of inactivation, the permittee notifies the Division of its intent to inactivate the certification, and certifies that the site has been finally stabilized; 2) In the case of inactivation, the permittee has ceased any and all discharges to state waters and demonstrates to the Division there is no probability of further uncontrolled discharge(s) which may affect waters of the State. 3) The Division finds that the pennittee has shown reasonable grounds consistent with the Federal and State statutes and regulations for such modification, amendment or inactivation; 4) Fee requirements of Section 61 . 15 of the Colorado Discharge Permit System Regulations have been met; and 5) Applicable requirements of public notice have been met. For small construction sites covered by a Qualifying Local Program, coverage under this permit is automatically terminated when a site has been finally stabilized. B. RESPONSIBILITIES (cont.) 5. Permit Violations Failure to comply with any terms and/or conditions of this permit shall be a violation of this permit. Dischargers of stormwater associated with industrial activity, as defined in the EPA Stormwater Regulation (40 CFR 122.26(b)(14) and Section 61 .3(2) of the Colorado Discharge Permit System Regulations, which do not obtain coverage under this or other Colorado general permits, or under an individual CDPS permit regulating industrial stormwater, will be in violation of the federal Clean Water Act and the Colorado Water Quality Control Act, 25-8-101 , as amended. Failure to comply with CDPS permit requirements will also constitute a violation. 6. Legal Responsibilities The issuance of this permit does not convey any property or water rights in either real or personal property, or stream flows, or any exclusive privileges, nor does it authorize any injury to private property or any invasion of personal rights, nor any infringement of Federal, State or local laws or regulations. Nothing in this permit shall be construed to preclude the institution of any legal action or relieve the permittee from any responsibilities, liabilities, or penalties established pursuant to any applicable State law or regulation under authority granted by Section 510 of the Clean Water Act. 7. Severability The provisions of this permit are severable. If any provisions of this permit, or the application of any provision of this permit to any circumstance, are held invalid, the application of such provision to other circumstances and the application of the remainder of this permit shall not be affected. 8. Renewal Application If the permittee desires to continue to discharge, a permit renewal application shall be submitted at least ninety (90) days before this permit expires. If the permittee anticipates that there will be no discharge after the expiration date of this permit, the Division should be promptly notified so that it can inactivate the certification in accordance with Part II.B.4.d. 9. Confidentiality Except for data determined to be confidential under Section 308 of the Federal Clean Water Act and Colorado Discharge Permit System Regulations, Section 61 .5(4), all reports prepared in accordance with the terms of this permit shall be available for public inspection at the offices of the Division. The permittee must state what is confidential at the time of submittal. Any information relating to any secret process, method of manufacture or production, or sales or marketing data which has been declared confidential by the permittee, and which may be acquired, ascertained, or discovered, whether in any sampling investigation, emergency investigation, or otherwise, shall not be publicly disclosed by any member, officer, or employee of the Commission or the Division, but shall be kept confidential. Any person seeking to invoke the protection of this section shall bear the burden of proving its applicability. This section shall never be interpreted as preventing full disclosure of effluent data. 10. Fees The permittee is required to submit payment of an annual fee as set forth in the Water Quality Control Act. Failure to submit the required fee when due and payable is a violation of the permit and will result in enforcement action pursuant to Section 25-8-601 et. seq., C.R.S. 1973 as amended. B. RESPONSIBILITIES (cont.) 11 . Requiring an Individual CDPS Permit The Director may require the permittee to apply for and obtain an individual or alternate general CDPS permit if: a) The discharger is not in compliance with the conditions of this general permit; b) Conditions or standards have changed so that the discharge no longer qualifies for a general permit; or c) Data/information become available which indicate water quality standards may be violated. The permittee must be notified in writing that an application for an individual or alternate general CDPS permit is required. When an individual or alternate general CDPS permit is issued to an operator otherwise covered under this general permit, the applicability of this general permit to that operator is automatically inactivated upon the effective date of the individual or alternate general CDPS permit. Water Quality Control Division WQCD-P-B2 4300 Cherry Creek Drive South Denver, Colorado 80246-1530 RATIONALE STORMWATER DISCHARGES ASSOCIATED WITH CONSTRUCTION UCTION ACTIVITY GENERAL PERMIT IN COLORADO THIRD RENEWAL COLORADO DISCHARGE PERMIT NUMBER COR-030000 CONTENTS PAGE I. Introduction 1 II. Changes in this General Permit I 111. Background b' IV. Stormwater Discharges Associated with Construction Activity 9 V. Coverage Under this Permit 10 VI Application and Certification 10 VII Qualifying Local Programs 11 VIII Terms and Conditions of Pennit 11 IX Public Notice — 12/22/06 15 X Public Notice — 3/23/07 15 L INTRODUCTION This permit is for the regulation of stormwater runoff from construction activities, and specific allowable non- stormwater discharges in accordance with Part I.D.3 of the permit. The term "construction activity" includes ground surface disturbing activities, including, but not limited to, clearing, grading, excavation, demolition, installation of new or improved haul and access roads, staging areas, stockpiling of fall materials, and borrow areas. "Stormwater" is precipitation-induced surface runoff. This rationale will explain the background of the Stormwater program, activities which are covered under this permit, how to apply for coverage under this permit, and the requirements of this permit The forms discussed in the rationale and permit are available on the Water Quality Control Division 's website at: www.cdphe.state.co.us/wq/PermitsUnit IL CHANGES IN THIS GENERAL PERMIT Several notable changes from the previous General Permit for Construction Activities have been incorporated into this permit. Significant changes are listed below. Numerous other minor changes were made for clarification purposes only. A. Authority to Discharge This section has been restructured to list all of the types of activities covered by this permit, and to be consistent with the definition of "construction activity. " The definition of construction activity has been expanded to provide clarification. See Part LA.1 of the permit. PART II Permit - Page 24 Permit No. COR-030000 IL CHANGES IN THIS GENERAL PERMIT (cont.) B. Authority to Discharge — Oil and Gas Construction This section has been added, to take into account a regulatory change. The federal Energy Policy Act of' 2005 exempts nearly all oil and gas construction activities from federal requirements under the Clean Water Act 's NPDES stormwater discharge permit program. In January 2006, the Colorado Water Quality Control Commission held a hearing to determine what effects, if any, the change in federal law would have upon Colorado 's stormwater regulations. The Commission determined that oil and gas construction sites in Colorado that disturb one or more acres are still required to be covered under Colorado 's stormwater permitting regulations (Colorado Discharge Permit System (CDPS) regulations (5CCR 1002-61)). In practice, oil and gas construction sites have the same requirements under this permit as do other types of construction. However, this permit contains some references to the federal Clean Water Act; generally these references are not applicable to oil and gas construction sites to the extent that the references are limited by the federal Energy Policy Act of 2005. See Part I.A.1(b) of the permit. C. Application Requirements The permit application requirements have changed slightly, including the addition of an email address, if available. See Part LA.4(b). The applicant must be either the owner and/or- operator of the construction site. An operator at a construction site that is not covered by a certification held by an appropriate entity may be held liable for operating without the necessary permit coverage. D. Temporary Coverage Part LA.5(d) of the previous permit (effective July 1, 2002) dealt with temporarily covering a facility under the general permit even Van individual permit is more appropriate. This permit section essentially duplicated the previous section (see Pail LA.5(c)), and so it has been deleted. E. Reassignment of Permit Coverage Procedures have been added to clarify the requirements for the transfer of coverage of specific portions of a permitted site to a second party. See Section VIII.L3 of the rationale and Part LA.8 of the permit. F. Individual Permit Criteria This section has been modified to include situations involving a Total Maximum Daily Load (TMDL). See Part LA. 11 of the permit. G. Stormwater Management Plan (SWMP) The Stormwater Management Plan section has been divided into two parts: Stormwater Management Plan (SWMP) — General Requirements, which provides the basic framework and general requirements for the SWMP, and Stormwater Management Plan (SWMP) — Contents, which specifically identifies each item that must be addressed in the SWMP. See Parts LB and LC of the permit. H. Stormwater Management Plan (SWMP) — General Requirements The SWMP General Requirements section has been modified to require that the SWMP be updated in accordance with Parts LD.5(c) and LD.5(d) of the permit (SWMP Review/Changes). This additional requirement ensures that the SWMP provisions reflect current site conditions. See Part LB.2(c) of the permit. PART II Permit - Page 25 Permit No. COR-030000 II. CHANGES IN THIS GENERAL PERMIT (cons) Stormwater Management Plan (SWMP) — Contents The SWMP Contents section has been modified. Some of the changes are limited to organization of information, which does not require modification of an existing permittee 's current SWMP. Most of the SWMP changes involve either clarifications, reformatting, or taking recommendations from the Division 's SWMP guide and making them permit requirements (e.g., vehicle tracking controls, BMP installation specifications). If an existing permittee (i.e., those with permit coverage before June 30, 2007)followed the recommendations in the SWMP guide (Appendix A of the permit application), then their SWMP will presumably meet the new requirements. However, for any existing permittees who did not follow the applicable SWMP guide recommendations, their SMWP must be amended to include the new required items: -SWMP Administrator -Identification of potential pollutant sources -Best Management Practices descriptions and installation specifications, including dedicated concrete or asphalt batch plants; vehicle tracking control; and waste management and disposal (including concrete washout activities). For existing permittees, any SWMP changes based on the change in permit requirements must be completed by October 1, 2007. The plan is not to be submitted to the Division unless requested, but must be available on site as outlined in Part I.D.5(b) of the permit. The BMP requirement clarifications included in this renewed permit in no way imply that adequate BMPs to address all pollutant sources at a permitted site were not required in previous permits. The revised requirements are intended only to better clarify SWMP content requirements and provide improved direction to permittees. The SWMP changes are listed below. All new applicants (after June 30, 2007)for permit coverage for their sites must fully comply with the new SWMP organization, plan requirements, and implementation. 1. Site Description: The requirement to provide an estimate of the run-off coefficient has been removed. The run-off coefficient as currently utilized in the SWMP may not contribute sufficiently to permit compliance to justify the effort in determining accurate values. See Part I. C.1 of the permit. However, the Division still encourages use of the coefficient as needed to adequately evaluate site-specific BMP selection and design criteria (e.g., pond capacities, BMP location, etc.) See Section C.2 of the SWMP guidance (Appendix A of the permit application). 2. Site Map: The requirement to ident y boundaries of the 100 year flood plain has been removed. The boundaries as currently utilized in the SWMP may not contribute sufficiently to permit compliance to justify the effort in determining their location. See Part I.C.2 of the permit. 3. Stormwater Management Controls: This section has been modified to require identification of a SWMP Administrator and all potential pollutants sources in the SWMP. See Part I.C.3 of the permit. a) The SWMP Administrator is a specific individual(s), position or title who is responsible for the process of developing, implementing, maintaining, and revising the SWMP. This individual serves as the comprehensive point of contact for all aspects of the facility 's SWMP. This requirement may necessitate changes to existing permittees' SWMPs. PART II Permit - Page 26 Permit No. COR-030000 II. CHANGES IN THIS GENERAL PERMIT (cont.) b) The requirement to identffj, Potential Pollutant Sources has been expanded to include more details for the evaluation of such sources. This evaluation allows for the appropriate selection of BMPs for implementation at a facility or site. Additionally, this section was added to be consistent with the SWMP guide. This requirement may necessitate changes to existing permittees' SWMPs. c) Best Management Practices (BMPs)for Stormwater Pollution Prevention: This section was modified to require the following items to be addressed in the SWMP. These requirements may necessitate changes to existing permittees' SWMPs. This section also requires that the SWMP provide installation and implementation specifications for each BMP identified in the SWMP. For structural BMPs, in most cases, this must include a technical drawing to provide adequate installation specifications. See Part I.C.3(c). i) Dedicated concrete or asphalt batch plants. This section requires that the practices used to reduce the pollutants in stormwater discharges associated with dedicated concrete or asphalt batch plants be identified in the SWMP. (Coverage under the construction site SWMP and permit is not required for batch plants if they have alternate CDPS permit coverage.) ii) Vehicle tracking control. This section requires that practices be implemented to control sediment from vehicle tracking, and that all such practices implemented at the site be clearly described in the SWMP. iii) Waste management and disposal. This section requires that the practices implemented at the site to control stormwater pollution from construction site waste, including concrete washout activities, be clearly described in the SWMP. It also requires that concrete washout activities be conducted in a manner that does not contribute pollutants to surface waters or stormwater runoff. iv) Concrete Washout Water. Part I.D.3(c) of the permit has been revised to conditionally authorize discharges to the ground of concrete wash water from washing of tools and concrete mixer chutes when appropriate BMPs are implemented. The permit prohibits the discharge of concrete washout water to surface waters and to storm sewer systems. Part I.C.3(c)(7) of the permit requires that BMPs be in place to prevent surface discharges of concrete washout water from the site. The use of unlined pits to contain concrete washout water is a common practice in Colorado. The Division has further evaluated the need for a permit for discharge of concrete washout water to the ground. The Division has determined that the use of appropriate BMPs for on-site washing of tools and concrete mixer chutes would prevent any significant discharge to groundwater. BMPs to protect groundwater are required by Part I.C.3(c)(7) of the permit. Because pH is a pollutant of concern for washout activities, the soil must have adequate buffering capacity to result in protection of the groundwater standard, or a lines/containment must be used. The following management practices are recommended to prevent an impact from unlined pits to groundwater: (1) the use of the washout site should be temporary (less than 1 year), and (2) the washout site should be not be located in an area where shallow groundwater may be present, such as near natural drainages, springs, or wetlands. PART II Permit - Page 27 Permit No. COR-030000 II. CHANGES IN THIS GENERAL PERMIT (cont.) Where adequate management practices are not followed to protect groundwater quality, the Department may require discharges to unlined pits to cease, or require the entity to obtain alternate regulatory approval through notice from either the Water Quality Control Division or the Hazardous Materials and Waste Management Division. In addition, Part I.D. 1(b) of the permit has been revised to clearly state that the permit does not authorize on-site permanent disposal of concrete washout waste, only temporary containment of concrete washout water from washing of tools and concrete mixer chutes. Upon termination of use of the washout site, accumulated solid waste, including concrete waste and any contaminated soils, must be removedfrom the site to prevent on-site disposal of solid waste. v) Construction Dewatering. Part LD.3(d) of the permit has been revised to conditionally authorize discharges to the ground of water from construction dewatering activities when appropriate BMPs are implemented. The permit does not authorize the discharge of groundwater from construction dewatering to surface waters or to storm sewer systems. Part I.C.3(c)(8) of the permit requires that BMPs be in place to prevent surface discharges. The permittee may apply for coverage under a separate CDPS discharge permit, such as the Construction Dewatering general permit, if there is a potential for discharges to surface waters. The Division has determined that potential pollutant sources introduced into groundwater .from construction dewatering operations do not have a reasonable potential to result in exceedance of groundwater standards when the discharge is to the ground. The primary pollutant of concern in uncontaminated groundwater is sediment. Although technology- based standards for sediment do exist in 5 CCR 1002-41, the discharge of sediment to the ground as part of construction dewatering does not have the reasonable potential to result in transport of sediment to the groundwater table so as to result in an exceedance of those standards. For a discharge of water contaminated with other pollutants that are present in concentrations that may cause an exceedance of groundwater standards, separate CDPS discharge permit coverage is required. Contaminated groundwater may include that contaminated with pollutants from a landfill, mining activity, industrial pollutant plume, underground storage tank, or other source of human-induced groundwater pollution and exceeding the State groundwater standards in Regulations 5 CCR 1002-41 and 42. J. Terms and Conditions, General Limitations and Design Standards This section reiterates the requirement that facilities select, install, implement, and maintain appropriate BMPs, following good engineering, hydrologic and pollution control practices. In addition, requirements for protection of water quality standards (see Part I.D.1.(a) of the permit) and requirements to adequately design BMPs to prevent pollution or degradation of State waters (see Part I.D.2 of the permit) have been revised and are fully discussed in Part IILB of the rationale, below. Additional language was also added to Section If B of the rationale further claming the expectations for compliance with this permit. 1. Management of'Site Waste This section has been modified to clarify that on-site waste must be properly managed to prevent potential pollution of State waters, and that this permit does not authorize on-site waste disposal. Solid waste disposal is regulated by the Hazardous Materials and Waste Management Division. PART II Permit - Page 28 Permit No. COR-030000 II. CHANGES IN THIS GENERAL PERMIT (cont.) K Terms and Conditions, SWMP Requirements 1. SWMP Review/Changes: This section now requires that when changes are made to site conditions, the SWMP must be revised immediately, except for some BMP description changes which conditionally may occur within 72 hours. This requirement is included to both ensure that the SWMP be kept accurate and up-to-date, and to clam that stormwater management at a site typically should be proactive instead of responsive, and be integrated into site management to ensure it is calibrated with those changes. The section was also clarified to state that only changes in site conditions that do not require new or modified BMPs do not need to be addressed in the SWMP. See Pan LD.S(c) of the permit. 2. SWMP Certification: The previous permit was unclear on a requirement that the copy of SWMP that remains at the facility had to be signed in accordance with permit signatory requirements. This requirement has been deleted. The signatory requirement of Part I.F. 1 only applies to the SWMP if it is to be submitted to the Division or to EPA. See Part I.F. 1 of the permit. L. Terms and Conditions, Post-Storm Inspections The previous permit required post-storm inspections, but did not speck the timing of inspections. This section now requires that post-storm event inspections generally be conducted within 24 hours of the event An alternative timeline has been allowed, only for sites where there are no construction activities occurring following a storm event For this condition, post-storm event inspections shall instead be conducted prior to commencing construction activities, but no later than 72 hours following the storm event, and the delay noted in the inspection report. Any exception from the minimum inspection schedule is temporary, and does not eliminate the requirement to perform routine maintenance due to the effects of a storm event, including maintaining vehicle tracking controls and removing sediment from impervious areas. In many cases, maintenance needs will require a more frequent inspection schedule than the minimum inspections required in the permit, to ensure that BMPs continue to operate as needed to comply with the permit See Part I.D.6(a) of the permit M. Terms and Conditions, Inspections 1. The Winter Conditions Inspection Exclusion section has been modified to include documentation requirements for this exclusion. See Part I.D.6(a) of the permit The Inspection Scope has been modified to include the requirement to inspect waste storage areas during inspections conducted in accordance with the permit See Part I.D.6(b) of the permit 2. The requirements for sites to quay for reduced inspection frequencies for completed sites have been slightly modified (see Part LD.6(a)(2) of the permit,). The requirement now is that only construction activities that disturb the ground surface must be completed. Construction activities that can be conducted without disturbance of the ground surface;for example, interior building construction, and some oil well activities, would not prohibit a site from otherwise qualifying for the reduced inspection frequency. In addition, the requirement for the site to be prepared for final stabilization has been slightly modified to allow for sites that have not yet been seeded to qualify, as long as the site has otherwise been prepared for final stabilization, including completion of appropriate soil preparation, amendments and stabilization practice. This will allow for sites with seasonal seeding limitations or where additional seed application may be needed in the future to still qualify. PART II Permit - Page 29 Permit No. COR-030000 II. CHANGES IN THIS GENERAL PERMIT (cont.) 3. The Inspection Report/Records section (Part LD.6(b)(2)) was added to clarify requirements for inspection reports generated during an inspection conducted in accordance with Part I.D.6 of the permit. Inspection reports must be signed by the inspector, or the individual verifying the corrective action indicated in the inspection report, on behalf of the permittee. Inspection reports are not typically required to be submitted to the Division, and therefore, are not required to be signed and certified for accuracy in accordance with Part I.F. 1 of the permit. However, any inspection reports that are submitted to the Division must follow the signatory requirements contained in that section. N. Terms and Conditions, Maintenance, Repair, and Replacement of Control Practices These sections have been added to clarify requirements for maintaining the BMPs identified in the SWMP and for addressing ineffective or failed BMPs. BMP maintenance and site assessment to determine the overall adequacy of stormwater quality management at the site must occur proactively, in order to ensure adequate control of pollutant sources at the site. In most cases, if BMPs are already not operating effectively, or have failed, the issue must be addressed immediately, to prevent discharge of pollutants. See Parts LD. 7 and LD.8 of the permit. O. Total Maximum Daily Load (TMDL) A section on TMDLs has been added. This section gives a general outline of the additional requirements that may be imposed by the Division if the facility discharges to a waterbody for which a stormwater-related TMDL is in place. See Section VIII.C of the rationale and Part LD. 11 of the permit. P. Additional Definitions Part LE of the permit has been modified to remove the definition of runoff coefficient, as it is no longer a permit requirement. The definition for state waters has also been deleted, but can be found in Regulation 61. Q. Changes in Discharge The section on the types of discharge or facility changes that necessitate Division notification has been clarified. See Part II.A. 1 of the permit. R. Non-Compliance Notification The section on notification to the Division regarding instances of non-compliance has been amended to clarify which types of noncompliance require notification. See Part II.A.3 of the permit. S. Short Term Certifications The previous permit allowed small short-term construction activities to be authorized for a predetermined period from 3 to 12 months, and then automatically expire (an inactivation request did not need to be submitted). The issuance of these certifications has led to significant confusion and incidents of noncompliance resulting from permittees unintentionally letting their certifications expire prior to final stabilization, as well as issues regarding billing. Therefore, the provisions for short-term certifications have been deleted. T. Bypass The Division has revised the Bypass conditions in Part ILA.5 of the permit to be consistent with the requirements of Regulation 61.8(3)(i). The revised language addresses under what rare occurrences BMPs may be bypassed at a site. PART II Permit - Page 30 Permit No. COR-030000 HI. BACKGROUND As required under the Clean Water Act amendments of 1987, the Environmental Protection Agency (EPA) has established a framework for regulating municipal and industrial stormwater discharges. This framework is under the National Pollutant Discharge Elimination System (NPDES) program (Note: The Colorado program is referred to as the Colorado Discharge Permit System, or CDPS, instead of NPDES.) The Water Quality Control Division ("the Division ') has stormwater regulations (5CCR 1002-61) in place. These regulations require specific types of industrial facilities that discharge stormwater associated with industrial activity (industrial stormwater), to obtain a CDPS permit.for such discharge. The regulations specifically include construction activities that disturb one acre of land or more as industrial facilities. Construction activities that are part of a larger common plan of development which disturb one acre or more over a period of time are also included. A. General Permits The Division has determined that the use of general permits is the appropriate procedure for handling most of the thousands of industrial stormwater applications within the State. B. Permit Requirements This permit does not impose numeric effluent limits or require submission of effluent monitoring data in the permit application or in the permit itself. The permit instead imposes practice-based effluent limitations for stormwater discharges through the requirement to develop and implement a Stormwater Management Plan (SWMP). The narrative permit requirements include prohibitions against discharges of non-stormwater (e.g., process water). See Part 1.13.3 of the permit. The permit conditions,for the SWMP include the requirement for dischargers to select, implement and maintain Best Management Practices (BMPs) at a permitted construction site that adequately minimize pollutants in the discharges to assure compliance with the terms and conditions of the permit. Part 1.13.2 of the permit includes basic design standards for BMPs implemented at the site. Facilities must select, install, implement, and maintain appropriate BMPs, following good engineering, hydrologic and pollution control practices. BMPs implemented at the site must be adequately designed to control all potential pollutant sources associated with construction activity to prevent pollution or degradation of State waters. Pollution is defined in CDPS regulations (SCCR 1002-61) as man-made or man-induced, or natural alteration of the physical, chemical, biological, and radiological integrity of water. Utilizing industry-accepted standards for BMP selection that are appropriate for the conditions and pollutant sources present will typically be adequate to meet these criteria, since construction BMPs are intended to prevent the discharge of all but minimal amounts of sediment or other pollutants that would not result in actual pollution of State waters, as defined above. However, site-specific design, including ongoing assessment of BMPs and pollutant sources, is necessary to ensure that BMPs operate as intended. The permit further requires that stormwater discharges from construction activities shall not cause, have the reasonable potential to cause, or measurably contribute to an excursion above any water quality standard, including narrative standards for water quality. This condition is the basis for all CDPS Discharge permits, and addresses the need to ensure that waters of the State maintain adequate water quality, in accordance with water quality standards, to continue to meet their designated uses. It is believed that, in most cases, BMPs can be adequate to meet applicable water quality standards. If water quality impacts are noted, or the Division otherwise determines that additional permit requirements are necessary, they are typically imposed as follows: 1) at the renewal of this general permit or through a general permit specific to an industrial sector (if the issue is sector-based); 2) through direction from the Division based on the implementation of a TMDL (if the issue is watershed-based); or 3) if the issue is site-specific, through a revision to the certification from the Division based on an inspection or SWMP review, or through an individual permit. PART II Permit - Page 31 Permit No. COR-030000 III. BACKGROUND (cont.) Some construction sites may be required to comply with a Qualifying Local Program in place of meeting several of the specific requirements in this permit Sites covered by a Qualifying Local Program may not be required to submit an application for coverage or a notice of inactivation and may not be required to pay the Division 's annual fee. See Section VII of the rationale. C. Violations/Penalties Dischargers of stormwater associated with industrial activity, as defined in the CDPS regulations (SCCR 1002-61), that do not obtain coverage under this or other Colorado general permits, or under an individual CDPS permit regulating industrial stormwater, will be in violation of the Federal Clean Water Act and the Colorado Water Quality Control Act, 25-8-101. For facilities covered under a CDPS permit, failure to comply with any CDPS permit requirement constitutes a violation. As of the time of permit issuance, civil penalties for violations of the Act or CDPS permit requirements may be up to $10,000 per day, and criminal pollution of state waters is punishable by fines of up to $25,000 per day. IV. STORMWA TER DISCHARGES ASSOCIATED WITH CONSTRUCTION ACTIVITY The stormwater regulations (CDPS regulations (SCCR 1002-61)), require that stormwater discharges associated with certain industrial activities be covered under the permit program. Construction activity that disturbs one acre or more during the life of the project is specifically included in the listed industrial activities. This permit is intended to cover most stormwater discharges from construction facilities required by State regulation to obtain a permit A. Construction Activity Construction activity includes ground surface disturbing activities including, but not limited to, clearing, grading, excavation, demolition, installation of new or improved haul and access roads, staging areas, stockpiling of fill materials, and dedicated borrow/fill areas. Construction does not include routine maintenance to maintain original line and grade, hydraulic capacity, or original purpose of the facility. (The maintenance exclusion is intended for projects such as road resurfacing, and where there will be less than one acre of additional ground disturbed. Improvements or upgrades to existing facilities or roads, where at least one acre is disturbed, would not qualify as "routine maintenance. '9 Definitions of additional terms can be found in Part I.E of the permit. Stormwater discharges from all construction activity require permit coverage, except for operations that result in the disturbance of less than one acre of total land area and which are not part of a larger common plan of development or sale. A "larger common plan of development or sale " is a contiguous area where multiple separate and distinct construction activities may be taking place at different times on different schedules. B. Types of Discharges/Activities Covered 1. Stormwater: This permit is intended to cover most new or existing discharges composed entirely of stormwater from construction activities that are required by State regulation to obtain a permit. This includes stormwater discharges associated with areas that are dedicated to producing earthen materials, such as soils, sand, and gravel, for use at a single construction site. These areas may be located at the construction site or• at some other location. This permit does not authorize the discharge of mine water or process water from borrow areas. This permit may also cover stormwater discharges associated with dedicated asphalt plants and concrete plants located at a specific construction site. PART II Permit - Page 32 Permit No. COR-030000 IV. STORMWA TER DISCHARGES ASSOCIA TED WITH CONSTRUCTION ACTIVITY (cont.) 2. Process water: Under certain restrictions, discharges to the ground from construction dewatering, and from concrete washout activities, are also covered (see Parts I.C.3(c)(7), LC.3(c)(8), LD.3(c) and I.D.3(d) of the permit). C. Types of Activities NOT Covered 1. Stormwater: Aside from the sources listed in subparagraph B.1, above, this permit does not cover stormwater discharged from construction sites that is mixed with stormwater from other types of industrial activities, or process water of any kind. Other types of industrial activities that require stormwater discharge permits pursuant to different sections qf the regulations (Regulation 5 CCR 1002-61, Section 61.2(e)(iii)(A-I, K)J, are not covered by this permit 2. Process water: This permit also does not cover any discharge of process water to suiface waters. If the construction activity encounters groundwater, in order to discharge this groundwater to surface waters, a Construction Dewatering Discharge Permit (permit number COG-070000) must also be obtained. An application for this permit can be obtained from the Division at the address listed in Part LA.4(a) of the permit, or at the website in Section I qf the rationale. V. COVERAGE UNDER THIS GENERAL PERMIT Under this general permit, owners or operators of stormwater discharges associated with construction activity may be granted authorization to discharge stormwater into waters of the State of Colorado. This includes stormwater discharges associated with industrial activity from areas that are dedicated to producing earthen materials, such as soils, sand and gravel, for use at a single construction site, and dedicated asphalt plants and dedicated concrete plants. This permit does not pre-empt or supersede the authority of other local, state or federal agencies to prohibit, restrict or control discharges of stormwater to storm drain systems or other water courses within their jurisdiction. Authorization to discharge under the permit requires submittal of a completed application form and a certification that the SWMP is complete, unless the site is covered by a Qualifying Local Program. Upon receipt of all required information, the Division may allow or disallow coverage under the general permit VL APPLICATION AND CERTIFICATION At least ten days prior to the commencement of construction activities, the owner or operator of the construction site shall submit an original completed application which includes the signed certification that the SWMP is complete. Original signatures are required for the application to be considered complete. For small construction sites only, if the site is covered by a Qualifying Local Program (see below), submittal of an application is not required. For the purposes of this permit, the "operator " is the person who has day-to-day control over the project This can be the owner, the developer, the general contractor or the agent of one of these panics, in some circumstances. At different times during a construction project, different types of parties may satisfy the definition of "operator" and the certification may be transferred as roles change. (Note - Under the Federal regulations, this application process is referred to as a Notice of Intent, or NOL For internal consistency with its current program, the Division will continue to use the term "application. '9 A summary of the permit application requirements is found in the permit at Part I.A.4(b). If coverage under this general permit is appropriate, then a certification will be developed and the applicant will be certified under this general permit. PART II Permit - Page 33 Permit No. COR-030000 VII. QUALIFYING LOCAL PROGRAMS For stormwater discharges associated with small construction activity (i.e., one to five acre disturbed area sites), the permit includes conditions that incorporate approved qualifying local erosion and sediment control program (Qualifying Local Program) requirements by reference. A Qualifying Local Program is a municipal stormwater program for stormwater discharges associated with small construction activity that has been formally approved by the Division. The requirements for Qualifying Local Programs are outlined in Part 61.8(12) of the Colorado Discharger Permit System Regulations (also see the Division's "Qualifying Local Programs for Small Construction Sites - Application Guidance '9. Such programs must impose requirements to protect water quality that are at least as stringent as those required in this permit. A. Approval Termination A Qualifying Local Program may be terminated by either the Division or the municipality. Upon termination of Division approval of a Qualifying Local Program, any small construction activity required to obtain permit coverage under Section 61.3(2)(h) of the CDPS regulations (SCCR 1002-61), shall submit an application form as provided by the Division, with a certification that the Stormwater Management Plan (SWMP) is complete as required by Part LA.3 of the permit, within 30 days of Division notification. B. Approval Expiration Division approval of a Qualifying Local Program will expire with this general permit on June 30, 2012. Any municipality desiring to continue Division approval of their program must reapply by March 31, 2012. The Division will determine if the program may continue as a approved Qualifying Local Program. VIII. TERMS AND CONDITIONS OF PERMIT A. Coverage under a Qualifying Local Program — For Small Construction Sites Only For small construction sites (disturbing less than 5 acres) covered under a Qualifying Local Program (see Section VII, above), only certain permit requirements apply, as outlined below. The local program must have been formally designated by the Division to quay. Most municipalities have some type of local program and may require permits and fees. However, simply having a program in place does not necessarily mean that it is a qualifying program and that a State permit is not required. The local municipality is responsible for notifying operators and/or owners that they are covered by a Qual wing Local Program. As of May 31, 2007, the only approved Qualifying Local Programs within the state are for Golden, Durango and Lakewood. An updated list of municipalities with Qual fying Local Programs, including contact information, is available on the Divisions website at: http://www.cdphe.state.co.us/wq/Permits Unit/stormwater/construction.h tml. The Division reserves the right to require any construction owner or operator within the jurisdiction of a Qualifying Local Program covered under this permit to apply for and obtain coverage under the full requirements of this permit. 1. Permit Coverage: If a construction site is within the jurisdiction of a Qualifying Local Program, the owner or operator of the construction activity is authorized to discharge stormwater associated with small construction activity under this general permit without the submittal of an application to the Division. The permittee also is not required to submit an inactivation notice or payment of an annual fee to the Division. PART II Permit - Page 34 Permit No. COR-030000 VIII. TERMS AND CONDITIONS OF PERMIT (cont.) 2. Permit Terms and Conditions: The permittee covered by a Qualifying Local Program must comply with the requirements of that Qualifying Local Program. In addition, the following permit sections are applicable: a) Parts 1.A. 1, 1.A.2, and I.A.3: Authorization to discharge and discussion of coverage under the permit. b) Part LD. 1: General limitations that must be met in addition to local requirements. c) Parts I.D.2, I.D.3, I.D.4: BMP implementation, prohibition of non-stormwater discharges unless addressed in a separate CDPS permit, and requirements related to releases of reportable quantities. d) Part I.D. 11: Potential coverage under a Total Maximum Daily Load (TMDL). e) Part IS: Additional definitions. I) Part II (except for Parts ILA.1, IL B.3, ILB.8, and II.B. 10): Specifically includes, but is not limited to, provisions applicable in the case of noncompliance with permit requirements, and requirements to provide information and access. B. Stormwater Management Plans (SWMPs) Prior to commencement of construction, a stormwater management plan (SWMP) shall be developed and implemented for each facility covered by this permit. A certification that the SWMP is complete must be submitted with the permit application. The SWMP shall identify potential sources of pollution (including sediment) which may reasonably be expected to affect the quality of stormwater discharges associated with construction activity from the facility. In addition, the plan shall describe the Best Management Practices (BMPs) which will be used to reduce the pollutants in stormwater discharges from the construction site. (Note that permanent stormwater controls, such as ponds, that are used as temporary construction BMPs must be adequately covered in the SWMP.) Facilities must implement the provisions of their SWMP as a condition of this permit. The SWMP shall include the following items: 1. Site Description 2. Site Map 3. Stormwater Management Controls 4. Long-term Stormwater Management 5. Inspection and Maintenance (See Parts I.B. and LC of the permit for a more detailed description of SWMP requirements.) The Division has a guidance document available on preparing a SWMP. The document is included as Appendix A of the permit application, and is available on the Division 's website at www.cdphe.state.co.us/wq/PermitsUnit. Some changes have been made to the SWMP requirements. See Section III of the rationale for a discussion on permittee responsibilities regarding those changes. PART II Permit - Page 35 Permit No. COR-030000 VIII. TERMS AND CONDITIONS OF PERMIT (cont.) Master SWMP Often, a large construction project will involve multiple smaller construction sites that are within a common plan of development, or multiple well pads under construction within an oil and gas well field. Pollutant sources and the types of BMPs used can be relatively consistent in such cases. A permittee could significantly streamline the SWMP development process through the use of a master SWMP. SWMP information must be developed and maintained for all construction activities that exceed one acre (or are part of a common plan of development exceeding one acre) conducted within the permitted area. By developing a single master plan, the permittee can eliminate the need to develop repetitive information in separate plans. Such a plan could include two sections, one containing a reference section with information applicable to all sites (e.g., installation details and maintenance requirements for many standard BMPs, such as silt fence and erosion blankets), and the second containing all of the information specific to each site (e.g., site BMP map, drainage plans, details for BMPs requiring site specific design, such as retention ponds). As new activities begin, information required in the SWMP is added to the plan, and as areas become finally stabilized, the related information is removed. Records of information related to areas that have been finally stabilized that are removed from the active plan must be maintained for a period of at least three years from the date that the associated site is finally stabilized. C. Total Maximum Daily Load (TMDL) If the designated use of a stream or water body has been impaired by the presence of a pollutant(s), development of a Total Maximum Daily Load (TMDL) may be required. A TMDL is an estimate of allowable loading in the waterbody for the pollutant in question. Types of discharges that are or have the potential to be a significant source of the pollutant are also identified. If a TMDL has been approved for any waterbody into which the permittee discharges, and stormwater discharges associated with construction activity have been assigned a pollutant-specific Wasteload Allocation (WLA) under the TMDL, the Division will either: 1. Notify the permittee of the TMDL, and amend the permittee's certification to add specific BMPs and/or other requirements, as appropriate; or 2. Ensure that the TMDL is being implemented properly through alternative local requirements, such as by a municipal stormwater permit. (The only current example of this is the Cherry Creek Reservoir Control Regulation (72.0), which mandates that municipalities within the basin require specific BMPs for construction sites.) See Part I.D.11 of the permit,for further information. D. Monitoring Sampling and testing of stormwater for specific parameters is not required on a routine basis under this permit. However, the Division reserves the right to require sampling and testing on a case-by-case basis, in the event that there is reason to suspect that compliance with the SWMP is a problem, or to measure the effectiveness of the BMPs in removing pollutants in the effluent. See Part I.D. 1(e) of the permit. E. Facility Inspections Construction sites typically must inspect their stormwater management controls at least every 14 days and within 24 hours after the end of any precipitation or snowmelt event that causes surface erosion. At sites or portions of sites where ground-disturbing construction has been completed but a vegetative cover has not been established, these inspections must occur at least once per month. (At sites where persistent snow cover conditions exist, inspections are not required during the period that melting conditions do not exist. These PART II Permit - Page 36 Permit No. COR-030000 VIII. TERMS AND CONDITIONS OF PERMIT (cont.) conditions are only expected to occur at high elevations within the Colorado mountains.) For all of these inspections, records must be kept on.file. Exceptions to the inspection requirements are detailed in Part I.D. 6 of the permit. F. SWMP Revisions The permittee shall amend the SWMP whenever there is a change in design, construction, operation, or maintenance of the site, which would require the implementation of new or revised BMPs. The SWMP shall also be amended if it proves to be ineffective in achieving the general objectives of controlling pollutants in stormwater discharges associated with construction activity. The timing for completion of SWMP changes is detailed in Parts I.D.5(c) and I.D.5(d) of the permit. SWMP revisions shall be made prior to change in the,field, or in accordance with Part I.D.5 40 of the permit. G. Reporting The inspection record shall be made available to the Division upon request. Regular submittal of an annual report is not required in this permit. See Part I.D.9 of the permit. H. Annual Fee The permittee is required to submit payment of an annual fee as set forth in the Water Quality Control Act. Permittees will be billed for the initial permit fee within a few weeks of permit issuance and then annually, based on a July 1 through June 30 billing cycle. L Responsibility for Permit The permit certification for a site may be inactivated, once coverage is no longer needed. The certification may be transferred, if another party is assuming responsibility for the entire area covered by the certification. In addition, permit responsibility for part of the area covered by the certification may be reassigned to another party. These actions are summarized below. The Stormwater Program construction fact sheet explains these actions in further detail under the section on Multiple Owner/Developer Sites, and is available on the Division website at http://www.cdphe.state.co.us/wq/Permits Unit/stormwater/ConstFactSheet.PDF, Section F. 1. Inactivation Notice: When a site has been finally stabilized in accordance with the SWMP, the permittee shall submit an Inactivation Notice that is signed in accordance with Part LF. 1 of the permit. A summary of the Inactivation Notice content is described in Part LA.6 of the permit. A copy of the Inactivation Notice form will be mailed to the permittee along with the permit certification. Additional copies are available from the Division. For sites where all areas have been removed from permit coverage, the permittee may submit an inactivation notice and terminate permit coverage. In such cases the permittee would no longer have any land covered under their permit certification, and therefore there would be no areas remaining to finally stabilize. Areas may be removed from permit coverage by: -reassignment of permit coverage (Part LA.8 of the permit); -sale to homeowner(s) (Part LA.9 of the permit); or -amendment by the permittee, in accordance with Division guidance for areas where permit coverage has been obtained by a new operator or returned to agricultural use. PART II Permit - Page 37 Permit No. COR-030000 VIII. TERMS AND CONDITIONS OF PERMIT (cont.) 2. Transfer of Permit: When responsibility for stormwater discharges for an entire construction site changes from one individual to another, the permit shall be transferred in accordance with Part I.A. 7 of the permit. The permittee shall submit a completed Notice of Transfer form, which is available from the Division, and at www.cdphe.state.co.us/wq/PermitsUnit. If the new responsible party will not complete the transfer form, the permit may be inactivated if the permittee has no legal responsibility, through ownership or contract, for the construction activities at the site. In this case, the new owner or operator would be required to obtain permit coverage separately. 3. Reassignment of Permit When a permittee no longer has control of a specific portion of a permitted site, and wishes to transfer coverage of that portion of the site to a second party, the permittee shall submit a completed Notice of Reassignment of Permit Coverage form, which is available from the Division, and at www.cdphe.state.co.us/wq/PermitsUnit. The form requires that both the existing permittee and new permittee complete their respective sections. See Part LA.8 of the permit. J. Duration of Permit The general permit will expire on June 30, 2012. The permittee's authority to discharge under this permit is approved until the expiration date of the general permit. Any permittee desiring continued coverage under the general permit past the expiration date must apply for recertification under the general permit at least 90 days prior to its expiration date. Kathleen Rosow December 18, 2006 IX PUBLIC NOTICE — 12/22/06 The permit was sent to public notice on December 22, 2006. A public meeting was requested, and was held on February 2, 2007. Numerous comments were received on the draft permit. Responses to those comments, and a summary of changes made to the draft permit, are in a separate document entitled "Division Response To Public Comments. " The permit will be sent to a second public notice on March 23, 2007. Any changes resulting from the second public notice will be summarized in the rationale. Kathleen Rosow March 22, 2007 X PUBLIC NOTICE — 3/23/07 The permit was sent to public notice for a second time on March 23, 2007. Numerous comments were received on the second draft permit. Responses to those comments, and a summary of the additional changes made to the draft permit, are contained in a separate document entitled "Division Response To Public Comments Part II". This document is part of the rationale. Any changes based on the Division response are incorporated into the rationale and permit. The response document is available online at http://www.cdphe.state.co.us/wq/Perm its Unit/stormwater/construction.html, or by emailing cdphe.wgstorm@state.co.us, or by calling the Division at 303-692-3517. Kathleen Rosow May 31, 2007 APPENDIX B SITE-SPECIFIC INFORMATION APPENDIX C BMP MANUAL Best Management Practices ( BM Ps) Berm ( B) Description A berm is a ridge of compacted soil located at the top or base of a sloping disturbed area to contain or divert surface runoff. Berms may be constructed from either excavated topsoil or subsoil. The purpose of a berm is to control runoff velocity, divert onsite surface runoff to a sediment trapping device, divert clean water away from disturbed areas, and to provide a safe slope bather for vehicle traffic. Applicability Berms are usually appropriate for drainage basins smaller than five acres, but with modifications they can be capable of servicing areas as large as ten acres. With regular maintenance, earthen berms have a useful life span of approximately 18 months. Berms are applicable for the following applications: • Along the outside shoulder of an insloped road to ensure that runoff from the roadway drains inward and to protect the fill slope from continual disturbance during road blading and maintaining. • Upslope of cut or fill slopes to divert flows away from disturbed areas. • Downslope of cut or fill slopes to divert onsite runoff to a stabilized outlet or sediment trapping device, although diversions are more commonly used for this application. • Along the outside shoulder of a road to provide vehicle safety. Limitations • Berms may erode if not properly compacted and stabilized with vegetation. Berms which are adjacent to concentrated flows will require erosion blanketing. • If a berm crosses a vehicle roadway or entrance, its effectiveness can be reduced. Wherever possible, berms should be designed to avoid crossing vehicle pathways. 1 Design Criteria VAS E-. 2 �tit��•'� � �i ' 1 .5 �� 1 .� EART -1 BERM '�'4�. ` 1 �:1��► x \�� 4- DIRECTION FLOW Drawing: URS 2008 :E Construction Specifications 1 . Prior to berm construction, remove all trees, brush, stumps and other objects in the path of the berm and till the base of the berm before laying the fill. Fill may consist of topsoil or subsoil excavated during the construction of nearby roads or well pads. 2. For roadside berms, construct according to Figure B- 1 . 3. To remain effective, berms should be compacted with tracked equipment, if possible. 4. All berms shall have positive drainage to a stabilized outlet so that runoff does not collect in ponds on the upslope side of the berm, but instead flows along the berm until ti reaches a stabilized outlet. Field location should be adjusted as needed. Stabilized outlet may be a well- vegetated area, a well pad detention pond, or a sediment control such as a silt fence or sediment trap where sedment can settle out of the runoff before being discharged to surface water. 5. If the expected life span of the berm is greater than 15 days, it is strongly recommended that the berm be stabilized with vegetation or an erosion control blanket immediately after construction. Stabilization is required where concentrated flows are expected. 6. Berms should be constructed and fully stabilized prior to commencement of major upslope land disturbance. This will maximize the effectiveness of the structure as a storm water control device. Maintenance Considerations 2 The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Berms should be inspected for evidence of erosion or deterioration to ensure continued effectiveness. Berms should also be maintained at the original height. Any decrease in height due to settling or erosion, which impacts the effectiveness of the BMP, should be repaired imm Removal Berms should remain in place and in good condition until all upslope disturbed areas are permanently stabilized. There is no need to formally remove the berm on completion of stabilization until interim or final reclamation. References Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES). Construction Ste Storm Water Runoff Control. Washington, D.C., February, 2003. http://www.dec.state.ny.us/website/dow/toolbox/escstandards New York State Department of Environmental Conservation, New York Guidelines for Urban Erosion and Sediment Control. New York. Fourth Edition, 1997. http://www.dec.state.ny.us/website/dow/toolbox/escstandards Table B-1 Berm Stabilization Treatment Channel Grade Type (1) A (<5 Ac.) B (5- 10 Ac.) 1 0.5-3 .0% Hydro-seed and use Hydro-seed and use tackifier tackifier Seed and cover with 2 3 .0-5 .0% Hydro-seed and use erosion control tackifier blanket, or lined with 2-inch stone Seed and cover with Line with 4 to 8- 3 5 .0-8.0% inch control inch stone or rock blanket, or lined (2) with 2-inch stone Line with 4 to 8- 4 8.0-20.0% inch stone or rock Engineering Design (2) (1) In highly erodible soils, as defined by the local approving agency, refer to the next higher slope grade for type of stabilization. 3 (2) Site rock, if available, shall be broken into the required size. Check Dam (CD ) t• • ti r � , • . ✓ .. S r .\ ^. tr r ` • `�'.` , 1. ♦ . ..a _ Description Check dams are small, temporary dams constructed across a diversion or road side ditch. Check dams can be constructed using gravel, rock, sandbags, gravel bags, earth with erosion control blanketing, straw bales, or synthetic materials to slow the velocity of concentrated flow in a channel and thus reduce erosion. As a secondary function, check dams can also be used to catch sediment from the channel itself or from the contributing drainage area as storm water runoff flows through or over the structure. Applicability Check dams are most often used in small, open channels with contributing drainage area of less than 10 acres, and side slopes of 2: 1 or less. Check dams may be used in the following applications: • In diversion or roadside ditches where it is not practical to line the channel or implement other flow control and sediment control practices. • In diversions or roadside ditches where temporary seeding has been recently implemented but has not had time to take root and fully develop. • As a series of check dams, spaced at appropriate intervals, used in one of the above two applications. 4 • Rock ditch checks should be perpendicular to the flowlinc of the ditch. • Rock ditches must be designed so that water can flow over them, not around them. The ditch check should extend far enough so that the ground level at the ends of the check is higher than the low point on the crest of the check. The following table provides check spacing for a given ditch grade: Ditch Grade Check Spacing Check Spacing (Percent) (feet) (meters) 5 59 18 6 49 15 7 43 13 8 36 11 9 33 10 10 30 9 Limitations • Check dams should not be used in live, continuously flowing streams unless approved by an appropriate regulatory agency. • Check dams may require frequent removal of accumulated sediments. Darns should therefore be located in areas accessible to maintenance vehicles. • Leaves have been shown to be a significant problem by clogging check dams in the fall. Therefore, they might necessitate increased inspection and maintenance. • Straw bale check dams decompose over time, and may be consumed by livestock. 5 Design Criteria ROCK CHECK DAM AMC 9 0 MAC A PONT A O@SION LOG PLAN VIEW POW A POW A POET s ?'r Flow—� o� framer PONS A SNAIL a IWO 'sIM PONT F� FVAT4Qf' L = The distance such that points EROSION LOG DETAIL DITCH 9NSTA6,iAT:QJ IOM MOMS LOOS 9*1 Q RDRL' ern ARAN MD WS. A and B are of equal elevation. r Mfr_- r "r4 a SPACING BETWEEN CHECK DAMS From: Virginia Soil and Water Conservation Commission, 1985 6 WIRE AND ROCK } VARIES 'Jr NOT SHOWN FOR CLARITY 12" MIN SWALE / /� /� /\\/ / :2 $\\/\\// i\// i 3" EMBEDMENT SWALE ELEVATION 10" MIN ROCK SOCK -\\ FLOW aiNosi. 'I'A L \ / / �\\/\\/\\ \\ FILTERED \ EMBEDDED ROCK/\/\/\/ / `j )1/R , �/ RUNOFF / �/ // // // // // 'SOCK 3" IN SOIL / � / / / / • \ /\\ \\ \\ \\ \\ \\\\\ \\. \ , \, \\ \ \ \ \ \\ \\\/\\\/\\/\\\\\ \ . /// / //\//\//\/ / / / / ///EMBEDDED ROCK// \\\\A /\\/ , //\\�/��/%/\/\ \ \ \ \�\ SOCK 3" `N SOIL\�\\ L = THE DISTANCE SUCH THAT POINT A AND B ARE OF EQUAL ELEVATION. SWALE SPACING /MA RSS ROCK SOCK IN SWALE 7 Construction Specifications • Install straw bale check dams, rock check dams and other check dams according to Figures and respectively. Other types of check dams shall have similar designs. • Check dams should be located in areas accessible to maintenance vehicles for the periodic removal of accumulated sediments. • Dams should be installed with careful placement of the construction material. Mere dumping of the dam material into a channel is not appropriate and will reduce overall effectiveness. • Check dams can be constructed from a number of different materials. Most commonly, they are made of straw bales or rock. When using rock, the material diameter should be 4 to 8 inches depending on the expected velocity and quantity of runoff within the channel. Wattles or sand/gravel bags may also be used, but only if straw bales or rock is unavailable or not feasible for the location. Earth collected during excavation of diversions or roadside ditches may also be placed as check dams if covered with erosion control blanketing. • All check dams should have a maximum height of three feet with sufficient space up slope from the barrier to allow ponding, and to provide room for sediment storage. The center of the dam should be at least six inches lower than the edges. This design creates a weir effect that helps to channel flows away from the banks and prevent further erosion. • Additional stability can be achieved by implanting the dam material approximately six inches into the sides and bottom of the channel. • In order to be most effective, dams used in a series should be spaced such that the base of the upstream dam is at the same elevation as the top of the next downstream dam. • When installing more than one check dam in a channel, outlet erosion stabilization measures should be installed below the final dam in the series. Because this area is likely to be vulnerable to further erosion, riprap, erosion control blanket lining, or some other stabilization measure is highly recommended. Maintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). During inspection, large debris, trash, and leaves should be removed. The center of a check dam should always be lower than its edges. If erosion or heavy flows cause the edges of a dam to fall to a height equal to or below the height of the center, and the effectiveness of the check dam is compromised, repairs should be made immediately. Accumulated sediment should be removed from the upstream side of a check dam when the sediment has reached a height of the dam (measured at the center). Close attention should be paid to the repair of damaged or 8 rotting straw bales, end runs and undercutting beneath bales. Replacement of bales should be accomplished promptly. Removal Removal of check dams is optional. Check dams within roadside ditches are usually used as temporary controls, where other check dams may be left in place to silt out. If removing a check dam, all accumulated sediment should be removed. Removal of a check dam should be completed only after the contributing drainage area has been completely stabilized. Permanent vegetation should replace areas from which rock or other material has been removed. References Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002. http://ww.dot.state.co.us/enviromental.envWaterQual/wgms4.asp Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES). Construction Ste Storm Water Runoff Control. Washington, D.C., February 2003 . http://cfpud.epa.gov/npdes/stonnwater/menufbmps/con site.cfin Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization (RAPPS) of Oil and Gas Construction Stes April 2004. North Dakota Department of Health Division of Water Quality, A Guide to Temporary Erosion- Control Measures for Contractors Designers and Inspectors, June 2001 *Other materials may be used instead of straw. 9 Culvert (C ) Description Culverts are typically concrete, steel, aluminum, or plastic pipe used to move ditch water under the road or to direct stream flow under the road or construction area. Applicability Culverts are ideal on road grates less than 15%. For grades over 15%, it is difficult to slow down the water or remove it from road surface rapidly. On such steep grades, it is best to use frequently spaced relief culverts and drainage crossings culverts, with armored ditches (see RIPRAP [R]). Culverts may be used in the following applications. • As drainage crossing culverts in streams and gullies to allow normal drainage to flow under the traveled way. • As ditch relief culverts to periodically relieve the inside ditch line flow by piping water to the opposite side of the road where the flow can be dispersed away from the roadway. Culverts placed in natural drainages may be utilized for ditch relief. Limitations • If undersized, culverts are susceptible to plugging and require cleaning. • Culverts will not filter sediment. • Culverts are easily crushed if not properly designed. Design Criteria Pipe size can be determined using general design criteria, such as in table C- 1 , but is ideally based upon site specific hydrologic analysis. Depth The depth of culvert burial must be sufficient to ensure protection of the culvert barrel for the design life of the culvert. This requires anticipating the amount of material that may be lost to road use and erosion. 10 Headwalls Use headwalls on culvert pipes as often as possible (see RETAINING WALL [RW]). The advantages of headwalls include: preventing large pipes from floating out of the ground when they plug; reducing the length of the pipe capacity; helping to funnel debris through the pipe; retaining the backfill material; and reducing the chances of culvert failure if it is overtopped. Construction Specifications Drainage crossing culverts • Make road crossings of natural drainages perpendicular to the drainage to minimize pipe length and area of disturbance (Figure C-1 ). • Use single large pipes versus multiple smaller diameter pipes to minimize plugging potential in most channels (unless roadway elevation is critical). In very broad channels, multiple pipes are desirable to maintain the natural flow spread across the channel. All culverts should be concrete corrugated metal pipe made of steel or aluminum, or properly bedded and backfilled corrugated plastic pipe. • Align culverts in the bottom and middle of the natural channel flowline so that installation causes no change in the stream alignment or stream bottom elevation. Culverts should not cause damming or pooling or increase stream velocities significantly. • Extend the outlet of the culvert at least one foot beyond the toe of the slope to prevent erosion of the fill material. Alternatively, use retaining walls (headwalls) to hold back the fill slope. • It may be necessary to install rip-rap, erosion control blanketing, a combination of both, or other energy dissipater device at the outlet end of the culvert to reduce soil erosion or to trap sediment (see CULVERT PROTECTION [CP]). • It may be desirable to construct pulloffs/turnouts for vehicle on one or both sides of narrow culvert crossings. This will help avoid culvert crushing as well as disturbance to roadside ditches and berms. Ditch relief culverts • See figure C-2 for installation details. 11 • Ditch relief culverts can provide better flow when skewed 0 to 30 degrees perpendicular to the road. • The culvert gradient should be at least 2% greater than the approach ditch gradient. This improves the flow hydraulics and reduces siltation and debris from plugging the culvert inlet. • Discharge culvert at natural ground level where possible ( see figure C-3,type A), on firm, non-erosive soil or in rocky or bushy areas. If discharge on the fill slopes, armor outlets with riprap or logging slash (see figure C-3, type B), or use down-drain structures (see figure C- 3, type C and SLOPE DRAIN [SD]). • Extend the inlet of the culvert at least one foot beyond the flowline of the roadside ditch. Extend the outlet of the culvert at least one foot beyond the toe slopes to prevent erosion of the fill material. • It may be necessary to install riprap or other energy dissipater devices at the outlet end of the culvert to prevent soil erosion or to trap sediment (see CULVERT PROTECTION [CP]). • Spacing of culverts is dependent on the road gradient, soil types, and runoff characteristics according to the following table: Road Grade Soil Type 2-4% 2-4% 2-4% Highly corrosive 240' 10' 140' granitic or sandy Intermediate erosive 310' 260' 200' clay or load Low erosive shale 400' 325' 250' or gravel • It may be desirable to construct pulloffs/turnouts for vehicle on one or both sides of narrow culvert crossings. This will help avoid culvert crushing as well as disturbance to roadside ditches and berms. 12 Backfill and Compaction See figure C-4. • Firmly compact well-graded fill material (soil or road base) around culverts, particularly around the bottom half, using placement in layers to achieve a uniform density. Use slightly plastic sandy gravel with fines. Avoid the use of fine sand and silt rich soils for bedding material because of their susceptibility to piping. Pay particular attention to culvert bedding and compaction around the haunches of the pipe. Do not allow the compaction to move or raise the pipe. In large fills, allow for settlement. • Cover the top of the metal and plastic culvert pipes with fill to a depth of at least 1 foot to prevent crushing by heavy trucks. Use a minimum cover of 2 feet of fill over concrete pipe. For maximum allowable fill height, follow manufacturer's recommendations. • Mound fill over the top of culvert pipes so that the road is slightly raised at culvert locations to help prevent erosion and water from ponding over culvert crossings. This practice, as well as placing large boulders around the culvert outlets, will also help to prevent culverts from crushing. M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). If any damage to culvert or inlet/outlet protection is noted or if there is any evidence of scour, repairs should be made immediately. Any debris that may be blocking the culvert inlet or outlet should be removed. References Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent practices for Stabilization (RAPPS) of Oil and Gas Construction 9tes April 2004. Keller, Gordon and James Sherar, Low-Volume Roads Engineering, Best Management Practices Field Guide. United States Department of Agriculture (USDA), Forest Service, US Agency od International Development (USAID), 2005. http://www.blm.gov/bmp/field%20guide.htm United States Department of the Interior and United States Department of Agriculture. Surface Operating Standards and Guidelines for Oil and Gas Exploration and Development " Gold Book". BLM/WO/ST-06/021 +3071 . Bureau of Land Management (BLM). Denver, Colorado. Fourth Edition, 2006. 13 Size of Drainage Structure (diameter and area) Drainage Area (acres) Steep Slopes (Light Vegetation) Gentle Slopes (Heavy Vegetation) C=0.7 C=0.2 Round Pipe ( In) Area (sq.ft) Round Pipe (In) Area (sq.ft) 0- 10 30" 4.9 18" 1 .8 10-20 42" 9.6 24" 3 . 1 20-35 48" 12.6 30" 4.9 35-75 72" 28.3 42" 9.6 75- 125 84" 38.5 48" 12.6 125-200 96" 50.3 60" 19.6 * Due to site specific conditions this table may not be used. 14 Drainage Crossing Culvert Alignment & Overflow Dip - I - r- � • y 3.11Et PROTECT1 I + ' .................1...........-..............::::-...............:•........:..........."...."..-...........1:-.......*..........-........1.-........:.......•....:•:::::::..........1.•:-...........::::::.:-.:. • • A gaps MyD CNx3S11m °ETOEWO CLL* •' •, .`•.' •—-• . 'C7 Inc +MW�C 1D IAVM?Z PfPL • • • • • • -•. • • **Mt..... •-' •1�Wv11i MC AKA or p5T.P84$ • �' �• • -- . • ,c. •• .•- �c� Eft C+:IvERT �� • 1FT. at i0TFE �!� RE Or SI0�E L to r arvmcnw Ditch Relief Culvert Installation --___..•46.0,0-- -•----• 46 46 ._ - -- - --46__46 .•---•-- d ,- Jr. ••♦,• �� 1.♦ R— Mstplalo::u us oat: \• Rosmcae ticA ��' • '.Turret";valor. "• .•r L rcassnip WO 1 Sp/CUg 140.400* Extinct culvert at lead 1'D-'/ond 1 t_ nrra�► lH+ vrl► baba u Of r 1 / : ': i Extend cult al r �, :1t?;C`A0•.. •, j • i"+ •� r �1 a 1' nsyorc la at slops •;i•• 1 C twit ' lam I !' Pt slaps -rr �+ f • •. .'h- } �� 4/ i n YY .• I y% , Flats WWI p pct at tts ifl round _ S• �• •; - laval or[trrap anrca QiaM t, M OS !.<• • NO1"TO SCALE 15 Culvert Installation Options TYPE A TYPE B SI j-- NILES psi ststss ¶ (/`Clf '\ .zbt Whitt 36% : - Gb�ete: ns— ,.,••• c 1 t / r• " -. Add 'Drag or tither trOtl►MM rte ms., Wart /� . ' : Caked — f TYPE C enelbM r t'EIfl aIr: F f • _ i' �.�r.r. l mato-fiea►adian :bea: hrR.sip r i� 1� / •8:M raiuls •ud! a"Cr Maass,et; Cuba) pt4u3✓t NOT TO SCALE �`` ?�. — -- Culvert Backfill and Compaction nm `N/ At bast 1 It of cps tb'afbr t a1 onet*dofdishaforbrys•aftvarla, Ikn 2 ft ac I SW"mDur overa.hnrt —\ tvn,010Rlpl�. . . . . _ . ..__ .$it\%.? _• ? • • • •• ' ' Wiwi . — ,,,;,')."..5. • . . A. teed'WWI st `R. ts,Ms Mtwwli Pill a er , `F`� Batts airs r raw.alt to avAaMM .� should bar rcmps' Oa patt �� •�,�> �. r tn. a mil um d oath cdnrt 'I 'I' 4\ •�,\ •,• .L Level oQ sslurd*otod ffumaw on arch slily a1 Ow dihrnK ii iMli at ail St bad Oven*Imps thin In ` NOT TO SCALE ,... 16 Culvert Protection (CP) a. Ippt �' ., b.: . N -'y ►. 7• ?► a • A _ •` 11/4,1 x- '�.,,, • il'-c* M- 4 i • � • � t2 Description Culvert protection may be required at the inlet of the culvert (upstream side) and/or the outlet side of the culvert (downstream side). Culvert inlet protection could involve placing boulders, riprap, gabions, rock retaining walls, slash, and/or any other protection at the inlet pipes. Riprap, or other energy-dissipating devices, will reduce the velocity of storm water flows and thereby prevent erosion and help protect the inlet structure. Culvert outlet protection involves placing structurally lined aprons or other appropriate energy- dissipating devices, such as large boulders or plunge pools, at the outlets of the pipes to reduce the velocity of storm water flows and thereby prevent scouring at storm water outlets, protect the outlet structure, and minimize potential for erosion downstream. Applicability Riprap inlet protection should be used where velocities and energies at the inlets of culvert are sufficient to erode around the inlet structure. Riprap may also be used to help channel the storm water to the inlet of the culvert. Culvert outlet protection should be used where discharge velocities and energies at the outlets of the culverts or channels are sufficient to erode the next downstream reach. Limitations Rock aprons at the culvert outlets should not be placed on slopes steeper than 10 percent. Runoff from pipe outlets at the top of cut/fills or on slopes steeper than 10 percent should be routed via slope drains or riprap chutes to a rock apron at the toe of the slope. Otherwise will re-concentrate and gain velocity as the flow leaves the apron. 17 Design Criteria Culvert inlet protection: Riprap, gabions, or rock retaining walls at culvert inlets shall be designed according to RIPRAP (R) or RETAINING WALL (RW). Culvert Outlet Protection: Gabions or rock retaining walls at culvert outlets shall be designed according to RETAINING WALL (RW). No formal design is required for plunge pools at outlets. Riprap aprons at culvert outlets shall be designed as follows. Tail-water depth: The depth of tail-water immediately below the pipe outlet must be determined for design capacity of the pipe. If the tail-water depth is less than half the diameter of the outlet pipe, and the receiving stream is wide enough to accept divergence of the flow, it shall be classified as a minimum tail-water condition. If the tail-water depth is greater than half the pipe diameter and the receiving stream will continue to confine the flow, it shall be classified as a maximum tail-water condition. Pipes that outlet onto flat areas with no defined channel may be assumed to have a minimum tail-water condition. Riprap Apron Size & D50: The apron length (LA) and the D50 of the riprap shall be determined from table CP-1 according to the design flow and weather there is a minimum or maximum tail- water condition. The apron width (W) shall then be determined as (W=d+0.4LA) where d is the diameter of the culvert. If the pipe discharges directly into a well defines channel, the apron shall extend across the channel bottom and up the channel banks to an elevation one foot above the maximum tail-water depth or to the top of the bank, whichever is less. The upstream end of the apron, adjacent to the pipe, shall have a width of two (2) times the diameter of the outlet pipe, or confirmed to pipe and section if used. Riprap M aterials The outlet protection may be done using rock riprap or grouted riprap. Riprap shall be composed of a well-graded mixture of stone size so that 50 percent of the pieces, by weight, shall be larger than the D50 size determined from table CP-1 . A well-graded mixture, as used herein, is defined as a mixture composed primarily of larger stone sizes, but with a sufficient mixture of other sizes to fill the smaller voids between the stones. The diameter of the largest stone size in such a mixture shall be 1 .5 times the D50 size. All grout for grouted riprap must be one part Portland cement for every three parts sand, mixed thoroughly with water. Filter : If a filter cloth or gravel is used, it should be designed according to RIPRAP (R). Apron Thickness The minimum thickness of the riprap layer shall be 1 .5 times the maximum stone diameter for D50 of 15 inches or less; and 1 .2 times the maximum stone size for D50 greater than 15 inches. Riprap Stone Quality: Stone for riprap shall consist of field stone or rough un-hewn quarry stone. The stone shall be hard and angular and of quality that will not disintegrate in exposure to water or weathering. The specific gravity of the individual stone shall be at least 2.5. Site rock or site boulders may be used provided it has a density of at least 150 pounds per cubic foot, and does not have any exposed steel or reinforcing bars. 18 Construction Specifications Culvert Inlet Protection: 1 . Riprap, gabions, or rock retaining walls at culvert inlets shall be constructed in accordance to RIPRAP (R) or RETAINING WALL (RW). 2. After installation of a culvert, examine the stream channel for the amount of debris, logs, and brushy vegetation present. In channels with large amounts of debris, consider using oversized pipes. 3 . Boulder should be dry-stacked around the culvert inlet and up the slope to the edge of the road. Culvert outlet protection: Gabions or rock retaining walls at culvert outlets shall be designed according to RETAINING WALL (RW). Riprap aprons at culvert outlets shall be constructed according to CP-2 and as follows. 1 . Prepare the sub-grade for the riprap to the required lines and grades. Any fill required in the sub-grade shall be compacted to a density of approximately that of the surrounding undisturbed material. 2. If a pipe discharges into a well-defined channel, the channel's side slopes may not be steeper than 2: 1 . 3. Construct apron to the design length and width with no slope. The invert elevations must be equal at the receiving channel and the apron's downstream end. No over-fall at the end of the apron of the apron is allowed. The elevation of the downstream and of the apron shall be equal to the elevation of the receiving channel or adjacent ground. The outlet protection apron shall be located so that there are no bends in the horizontal alignment. 4. If a culvert outlets at the top of cut/fills or on slopes steeper than 10 percent one of the following option is suggested: 5. Line slope below culvert outlet with a riprap channel to convey storm water to the bottom of the slope where a riprap apron, as designed above, shall prevent erosion at the bottom of the slope. The riprap channel shall be designed according to the table in the RIPRAP (R) construction specification that is based on depth of flow and slope. The riprap channel shall dip into the slope so that all water is contained within the channel, flows to the riprap outlet apron at the base of the slope, and does not spill over the sides onto unprotected soil. 19 M aintenan©e Considerations The frequency of inspection should be in accordance with the Storm Water Management Plan (SWMP). Inspect for debris at the entrance to culverts and within culverts. Inspect riprap at culvert inlets for damage and dislodged stones. The maintenance needs are usually very low for properly installed riprap aprons at culvert outlets. However, inspect for evidence of scour beneath riprap at outlets aprons or for dislodged stones. Anything that is found to reduce the effectiveness of the culvert or culvert outlet protection should be repaired immediately. References Keller, Gordon and James Sherar, Low-Volume Roads Engineering, Best Management Practices Field Guide. United States Department of Agriculture (USDA), Forest Service, US Agency od International Development (USAID), 2005. http://www.blm.gov/bmp/field%20guide.htm New York State Department of Environmental Conservation, New York Guidelinesfor Urban Erosion and Sediment Control. New York. Forth Edition, 1997.http://www.dec.state.ny.us/website/dow/toolbox/escstandards 20 Riprap Aprons for Low Tailwater (downstream flow depth < 0.5 x pipe diameter) Culvert Lowest Value I ntermediate values to interpolate from Highest Value Diameter Q LA O50 Q LA D50 Q LA O50 Q LA O50 Q LA D50 Cfs Ft I n Cfs Ft In Cfs Ft In Cfs Ft In Cfs Ft In 12" 4 7 2.5 6 10 3 .5 9 131 6 12 16 7 14 17 8.5 15 " 6.5 8 3 10 s 12 5 15 16 7 20 18 10 25 20 12 18" 10 9 3 .5 15 14 5 .5 20 17 7 30 22 11 40 25 14 21 " 15 11 4 25 18 7 35 22 10 45 26 13 60 29 18 24" 21 13 s 5 35 s 20 8.5 50 26 12 65 30 16 80 33 19 27" 27 14 5 .5 50 24 9.5 70 29 14 90 34 18 110 37 22 30" 36 16 6 60 25 9.5 90 33 15 .5 120 38 20 140 41 24 36" 56 20 s 7 100 , 32 13 s 140 40 s 18 180 s 45 s 23 220 50 28 42" 82 22 8.5 120 32 12 160 39 17 200 45 20 260 52 26 48" 120 26 10 170 37 14 220 46 19 270 54 23 320 64 37 Riprap Aprons for High Tailwater (downstream flow depth > 0.5 x pipe diameter) Lowest Value I nter mediate val ues to interpolate from Highest Value Culvert Diameter Q LA O50 Q LA O50 Q LA O50 Q LA O50 Q LA O50 Cfs Ft I n Cfs Ft I n Cfs Ft I n Cfs Ft I n Cfs Ft I n 12" 4 8 2 6 18 2.5 9 28 4.5 s 12 s 36 7 14 40 8 15 " 7 8 2 10 s 20 2.5 s 15 s 34 5 s 20 s 42 s 7.5 25 50 10 18" 10 8 2 15 22 3 20 34 5 30 50 9 40 60 11 21 " 15 8 2 25 s 32 4.5 35 s 48 7 45 s. 58 s. 11 60 72 14 24" 20 8 2 35 s 36 5 50 55 8.5 s 65 68 12 80 80 15 27" 27 10 2 50 41 6 70 s 58 10 90 70 14 110 82 17 30" 36 11 2 60 s 42 6 90 64 s 11 s 120 80 15 140 90 18 36" 56 13 2.5 100 60 7 140 s 85 13 180 104 18 220 120 23 42" 82 15 2.5 120 50 6 160 75 10 s 200 96 14 260 120 19 48" 120 20 2.5 170 58 7 220 85 12 270 105 16 320 120 20 21 Typical Inlet Protection ... ...o avert � -.4 - l 1' beyond tow at slope "'1 . _.• ._• _ -, - f - ..... ........--. -- ** -c:k• teat.,..3essa," Roadside au.a ---• - - -- r, c� it-7::e .' +•-"� "' \ . rr• G tealn •er,ltd • ti ` Obnkel (tca) . •, '1 / , ,• _ • at Typical Outlet Protection "` ` _ r.. A r- Mid+0.4 La d 1 ��.. basi5,S.. It. ....3. ."--,•;* i alert 1'mn. ', beyond toed slope. %Nee: ,. 4-I(1.0 . , - • Qrsd ' .. A.•... . iNowt L -s' . .7.1 • 4i ��,r r {F =;yrj ' ,f�_? A. e+d • dil ♦ ;�F, •�w•r•',�a� ;•f'�y. «:�difa/�.• a+• +•! ti19+•`3t�Iitv�' • :. '�xr- C'tt� t' ., � y ti; r=r�t • 1 —r •:=(.-/S�i?iuf:� ��: ., ,f,'��• .S�.t :1=a�.us� • r -+ :» t. hs'•.• ..'.'r=a•. �• �.: .!r 4 %. • • t.�__4 ► 1`s(�`, >�+•�3�t•�r pl�Nl'C r 3 nln, A - • • i'-• • .�••lr�M7 i}M. wI �rr�r. r !1r Mme., _ titer O" flux at. •. y . t ► i LA / x NOT TO SCALE 7,• 22 Diversion Ditch Embankment Bases or M idslopes ( DD) COMPACTED EMBANKMENT USING EXCAVATED MATERIAL - 18" MIN 4.0%e FLOW PROPOSED GRADE MATERIAL TO BE EXCAVATED DIVERSION DITCH SECTION UNLINED CHANNEL EXISTING GRADE • DD CIO DIVERSION DITCH FOR EMBANKMENT BASES OR MIDSLOPES Diversion Ditch Installation Notes • See the Plan view for the location(s) of the diversion ditches. • A plastic liner, riprap, or erosion control blanket may be necessary to protect the diversion ditch. • All material excavated from the ditch shall be used to construct the berm on the downhill side of the ditch. • The diversion ditch shall be a minimum of 18" deep with 3 : 1 side slopes. The adjacent berm shall be a minimum of 18" in height with 3 : 1 side slopes. All embankments shall be firmly compacted. • The discharge from the diversion ditch shall be directed towards an appropriately sized and constructed slope drain, or sediment pond. 23 • In locations where construction traffic must cross a diversion ditch, the erosion control supervisor shall install a temporary culvert with a minimum diameter of 12". Diversion Ditch I nspection and Maintenance Notes • The erosion control supervisor shall inspect the diversion ditch at the following intervals: • Immediately following initial installation. • Every 14 days while the site is under construction. • Immediately following any storm event that causes soil erosion. • Once a month following the end of construction, until vegetative cover has reached a consistent density of at least 70% of full vegetative cover. • Accumulated sediment shall be removed once the sediment has reached a depth equal to 1/a the crest height. • Diversion ditches shall be re-graded immediately following any signs of soil erosion. • Diversion ditches are to remain in place and properly maintained until vegetative cover has reached a consistent density of at least 70% of full vegetative cover and erosion and sedimentation is no longer a possibility as determined by the County inspector. In some instances, the diversion ditches may remain in place permanently. • When diversion ditches are removed, excavation shall be filled with suitable compacted topsoil. The berm portion of the diversion ditch shall be graded out and any disturbed areas associated with the installation, maintenance, and/or removal of the diversion ditches shall be roughened, seeded, mulched, and crimped. An erosion control blanket may be used in lieu of straw mulch. 24 Erosion Control Blanket ( ECB) Description Erosion control blankets, also called turf reinforcement mats (TRM), are porous fabrics and are manufactured by weaving or bonding fibers made from organic or synthetic materials. Erosion control blankets are installed on steep slopes, over berms, or in channels to prevent erosion until final vegetation is established. However, blankets can also be used as separators or to aid in plant growth by holding seeds, fertilizers and topsoil in place. Applicability Erosion control blankets may be used in the following applications: • To control erosion on steep slopes and to promote the establishment of vegetation. • To stabilize channels against erosion from concentrated flows. • To protect berms and diversions prior to the establishment of vegetation. • To protect exposed soils immediately and temporary, such as when active piles of soil are left overnight. • As a separator between riprap and soil to prevent soil from being eroded from beneath the riprap and to maintain the riprap's base. • May be used on slopes as steep as 1 : 1 . Limitations • Blankets used on slopes should be biodegradable, or photodegradable, non-toxic to vegetation or germination of seed, and non-toxic or injurious to humans. • Should not be used on slopes where vegetation is already established. • Some blankets might promote increased runoff and might blow away if not firmly anchored. • If the fabric is not properly selected, designed, or installed, the effectiveness may be reduced drastically. Manufacturer's specification should be followed. 25 Design Criteria There are many types of erosion control blankets available. Therefore, the selected fabric should match its purpose. Effective netting and matting require firm, continuous contact between the material and the soil. If there is no contact, the material will not hold the soil and erosion will occur underneath the material. Table ECB- 1 indicates some recommended criteria for the selection of erosion control blankets. Construction Specifications • Smooth soil prior to installation and apply seed prior to fabric installation for stabilization of construction sites. • Select the appropriate fabric type using the guidelines from table ECB- 1 . • Installation of the blankets shall be in accordance with the manufacturer's recommendations and according to figure ECB- 1 . For blankets being placed in channels, the fabric should be rolled out parallel to the channel if the width is sufficient to cover the entire width of the channel. The fabric needs to be in continuous contact with the exposed soil. • Pins or staples shall be made of wire 0. 1621 " or larger in diameter. "U" shaped staples shall have legs 8" long, and a 1 " crown. The bar of the "T" shall be at least 4" long. Triangular survey stakes can also be used. M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Inspections should determine if cracks, tears, or breaches have formed in the fabric. If the effectiveness of the erosion control blanket has been reduced, the fabric should be repaired or replaced immediately. Re-anchor loosened matting and replace missing matting and staple as required. It is necessary to maintain contact between the ground and the blanket at all times. Trapped sediment should be removed after each storm event. References Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDEq. Construction Ste Storm Water Runoff Control. Washington, D.C., February 2003 . http://cfpud.epa.gov/npdes/stonnwater/menufbmps/con_site.cfm Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization (RAPPS) of Oil and Gas Construction Stes April 2004. 26 Keller, Gordon and James Sherar, Low-Volume Roads Engineering, Best Management Practices Field Guide. United States Department of Agriculture (USDA), Forest Service, US Agency od International Development (USAID), 2005. http://www.blm.gov/bmp/field%20guide.htm North American Green, 2004.<http://www.nagreen.com Table ECB-1 Suggested Blanket Types Max. Flow Description Longevity r Applications Velocity (feetfsec.} Single Net Straw Blanket 12 months 4:1 - 3: 1 Slopes Low Flow Channels Rapid Degrading Nei 45 - 60 4.1 - 3: 1 Slopes 5 Days Low Flow Channels Double Net Straw Blanket 12 months 3:1 - 2: 1 Slopes 6 Moderate Flow Channels Rapid Degrading Nets 45 - 60 3: 1 - 2: 1 Slopes 6 Days Moderate F low Channels Double Net Blanket 24 months 2:1 - 1:1 Slopes a 70% Straw/30% Coconut Medium Flaw Channels Double Net Blanket 36 months 1: 1 & Greater Slopes 10 100% Coconut High Flow Channels Double Net Blanket 1:1 Slopes 9 (unveg ) Polypropylene Fiber Extended Flow Areas 16 (veg ) High Flow Channels Organic Net 12 months 4:1 - 3:1 Slopes 5 Low Flow Channels Organic Nets 12 months 3: 1 - 2:1 Slopes 6 Moderate Flow Channels 16 months 2:1 - 1:1 Slopes a Medium Flow Channels 24 months J 1 :1 & Greater Slopes 10 High Flow Channels 27 Additional Drawings: Stap e detail r Detail 4 -- Detal3 Detail 2 . it IIP miernab-- • „---- Row • Detail 1 Column Erosion Control Blanket Persective View 4 in (102 mm) 3 in (76 mm) minimum 6 -12 in (152-305 mm) minimum — Staple Tamp soil firmly Staple Terminal Fold - Terminal Fold - jute mesh only excelsior blanket DETAIL 1 erosion control paper 12 in (305 mm) 12 in (305 mm) • 6in (152mm) �• •. Staples Staples Junction Slot - Junction Slot - jute mesh erosion j7 F TA, 7 excelsior blanket control paper Erosion Control Blanket: Detail 1 and Detail 2 Section View 28 Additional Drawings: 12 in (305 mm) r Tamp soil firmly Tamp soil firmly . 1I, �.� 6 -12 in ( 152-305 mm) . • minimum depth Staple Staples Anchor Slot - Check Slot - jute mesh erosion control paper excelsior blanket erosion control paper DETA L 3 DETAIL 4 4 in (102 mm) minimum 1 in (25 mm) minimum 6 -12 in (152-305 mm) 'it ,i• • minimum — ,4, • Staple . It Lap Joint - jute mesh STAPLE DETAIL excelsior blanket erosion control paper shall be butted togther DETAIL 5 Erosion Control Blanket; Detail 3, Detail 4, Detail 5, and Staple Detail Section View 29 FiltrexxO Sediment Control ( FSC ) �. , rt • V r a s i r • ;_ se 1 - Description Filtrexx® Sediment control is a three-dimensional tubular sediment control and storm water runoff filtration device typically used for perimeter control of sediment and other soluble pollutants (such as phosphorus and petroleum hydrocarbons), on and around construction activities. Applicability Filtrexx® Sediment control is to be installed down slope of any disturbed area requiring erosion and sediment control and filtration of soluble pollutants from runoff. Sediment control is effective when installed perpendicular to sheet or low concentrated flow. Acceptable applications include: • Site perimeters; • Above and below disturbed areas subject to sheet runoff, inter-rill and rill erosion; • Above and below exposed and erodible slopes; 30 • Around area drains or inlets located in a `sump'; • On compacted soils where trenching of silt fence is difficult or impossible; • Around sensitive trees where trenching of silt fence is not beneficial for tree survival or may unnecessarily disturb established vegetation; • On frozen ground where trenching of silt fence is impossible; and • On paved surfaces where trenching of silt fence is impossible. Limitations Filtrexx® Sediment control should not be placed on slopes steeper than 50 percent. Runoff from the top of cut/fills or on slopes steeper than 50 percent should be routed via other means through BMPs designed to manage surface flow. Appropriate diameter Filtrexx® Sediment control should be chosen based on the application. 31 Design Criteria Maximum Slope Length Above Sediment Control in Feet* 8 in Sed i ment 12 in Sed i ment 18 in Sed i ment 24 in Sediment 32 in Sediment Slope Percent control control control control control 6.5 in* * 9.5 in* * 14.5 in* * 19in* * 26in* * 2 (or less) 600 750 1000 1300 1650 5 400 500 550 650 750 10 200 250 300 400 500 15 140 170 200 325 450 20 100 125 140 260 400 25 80 100 110 200 275 30 60 75 90 130 200 35 60 75 80 115 150 40 60 75 80 100 125 45 40 50 60 80 100 50 40 50 55 65 i 75 * Based on a failure point of 36 in super silt fence (wire reinforced) at 1000 ft of slope, watershed width equivalent to receiving length of sediment control device, 1 in/ 24 hr rain event. * *Effective height of Sediment control after installation and with constant head from runoff as determined by Ohio State University. Construction Specifications 1 . Sediment control used for perimeter control of sediment and soluble pollutants in storm runoff shall meet Filtrexx® SoxxTM Material Specifications and use Certified Filtrexx® FilterMediaTM. 2. Contractor is required to be Filtrexx® CertifiedTM, or use pre-filled Filtrexx® Sediment control products manufactured by a Filtrexx® Certified ManufacturerTM as determined by Filtrexx® International, LLC (440-926-2607 or visit www.filtrexx.com). Certification shall be considered current if appropriate identification is shown during time of bid or at time of application. Look for the Filtrexx® CertifiedTM Seal. 3. Sediment control will be placed at locations indicated on plans as directed by the Engineer. 32 4. Sediment control should be installed parallel to the base of the slope or other disturbed area. In extreme conditions (i.e., 2: 1 slopes), a second Sediment control shall be constructed at the top of the slope. 5. Effective SoxxTM height in the field should be as follows: 8" Diameter Sediment control = 6.5" high, 12" Diameter Sediment control = 9.5" high, 18" Diameter SiltSoxxTM = 14.5" high, 24" Diameter Sediment control = 19" high. 6. Stakes shall be installed through the middle of the Sediment control on 10 ft centers, using 2 in by 2 in by 3 ft hard wood stakes. In the event staking is not possible, i.e., when Sediment control is used on pavement, heavy concrete blocks shall be used behind the Sediment control to help stabilize during rainfall/runoff events. 7. Staking depth for sand and silt loam soils shall be 12 in, and 8 in for clay soils. 8. Loose compost may be backfilled along the upslope side of the Sediment control, filling the seam between the soil surface and the device, improving filtration and sediment retention. 9. If the Sediment control is to be left as a permanent filter or part of the natural landscape, it may be seeded at time of installation for establishment of permanent vegetation. The Engineer will specify seed requirements. 10. Filtrexx® Sediment control is not to be used in perennial, ephemeral, or intermittent streams. M aintenance Considerations The frequency of inspection should be in accordance with the Storm Water Management Plan (SWMP) to make sure they maintain their shape and are producing adequate hydraulic flow- through. If ponding becomes excessive, additional Sediment control may be required to reduce effective slope length or sediment removal may be necessary. Sediment shall be removed at the base of the upslope side of the Sediment control when accumulation has reached 1/2 of the effective height of the Sediment control, or as directed by the Engineer. Alternatively, a new Sediment control can be placed on top of and slightly behind the original one creating more sediment storage capacity without soil disturbance. References Fi l trexx Land Improvement Systems, Specification Cut Sheets., Fi l trexx International, LLC, C, 2010.http://www.fi l trexx. comr/Resources/Secti on4. 1. 1-SWPPPCutShcct- Fi l trexxSedi mentControl.pdf 33 Hydraulic M ulch 4kri‘ j ro a Description and Purpose Hydraulic mulch consists of applying mixture of shredded wood fiber or a hydraulic matrix, and a stabilizing emulsion or tackifier with hydro-mulching equipment, which temporarily protects exposed soil from erosion by raindrop impact or wind. Applicability Hydraulic mulch is suitable for soil disturbed areas requiring temporary protection until permanent stabilization is established, and disturbed areas that will be re-disturbed following an extended period of inactivity. Limitations Wood fiber hydraulic mulches are generally short lived and need 24 hours to dry before rainfall occurs to be effective. May require a second application in order to remain effective for an entire rainy season. Construction Specif i cati ons • Prior to application, roughen embankment and fill areas by rolling with a crimping or punching type roller or by track walking. Track walking shall only be used where other methods are impractical. 34 • To be effective, hydraulic matrices require 24 hours to dry before rainfall occurs. • Avoid mulch over spray onto roads, sidewalks, drainage channels, existing vegetation, etc. • Paper based hydraulic mulches alone shall not be used for erosion control. Hydraulic Mulches Wood fiber mulch can be applied alone or as a component of hydraulic matrices. Wood fiber applied alone is typically applied at the rate of 2,000 to 4,000 lb/acre. Wood fiber mulch is manufactured from wood or wood waste from lumber mills or from urban sources. Hydraulic Matrices Hydraulic matrices include a mixture of wood fiber and acrylic polymer or other tackifier as binder. Apply as a liquid slurry using a hydraulic application machine (i.e., hydro seeder) at the following minimum rates, or as specified by the manufacturer to achieve complete coverage of the target area: 2,000 to 4.000 lb/acre wood fiber mulch, and 5 to logo (by weight) of tackifier (acrylic copolymer, guar, psyllium, etc.) Bonded Fiber Matrix Bonded fiber matrix (BFDI) is a hydraulically applied system of fibers and adhesives that upon drying forms an erosion resistant blanket that promotes vegetation, and prevents soil erosion. BFDIs are typically applied at rates from 3,000 lb/acre to 4,000 lb/acre based on the manufacturer's recommendation. A biodegradable BFM is composed of materials that are ioo°% biodegradable. The binder in the BFAI should also be biodegradable and should not dissolve or disperse upon re-wetting. Typically, biodegradable BFMs should not be applied immediately before, during or immediately after rainfall if the soil is saturated. Depending on the product, BFTIs typically require 12 to 24 hours to dry and become effective. 35 Land Grading ( LG ) Description Grading involves reshaping the ground surface to planned grades. Grading provides more suitable topography for well pads and pipelines and helps to control runoff, soil erosion, and sediment during and after construction in these areas. This BMP shall include the following: • Proper cut and fill techniques to ensure roads and well pads remain stable over time. • Road crowning or sloping to properly route runoff off the roadway. • Surfacing of roads or well pads with gravel to avoid mud, rutting, and large quantities of sediment that will wash away during storms. Applicability • This BMP is applicable to the construction and maintenance of any road or well pad, but particularly those located on steep topography or easily erodible soils. • Surface gravel is applicable to all areas with "soft" soils sections, steep grades, highly erosive soils, or where all weather access is needed. Gravel may be used as "fill" material in ruts or as a full structural section over the entire road or well pad. Limitations • Improper cut and fill slopes that disrupt natural storm water patterns might lead to poor drainage, high runoff velocities, and increased peak flows during storm events. • Rutting and wash boarding may develop if surface gravel is not designed properly or if road or well pad is not sloped. • Flat-blading to maintain the roadway must be done properly to avoid changes in gravel thickness, road slope, and road grade. Design Criteria Practices must be developed for erosion control, slope stabilization, and safe disposal of runoff water and drainage, such as ditches and culverts, grade stabilization structures, retaining walls, and surface drains. Land grading should be based upon well pad and pipeline layouts that fit and utilize existing topography and desirable natural surroundings to avoid extreme grade modifications. Clearing and grading should only occur at those areas necessary for well pad activity and equipment traffic. Maintaining undisturbed temporary or permanent buffer zones in 36 the grading operation provides a low cost sediment control measure that will help reduce runoff and offsite sedimentation. Slope Failures Landslides and failed cuts and fills can be a major source of sediment. They can close the roads or require major repairs, and they can greatly increase maintenance costs. Slope failures, or landslides typically occur where a slope is over-steep, where fill material is not compacted, or where cuts in natural soils encounter groundwater or zones of weak material. Good road location can often avoid landslide areas and reduce slope failures. When failure does occur, the slide area should be stabilized by removing the slide material, flattening the slope, adding drainage, or using structures as discussed below. Designs are typically site specific and may require input from geotechnical engineers and engineering geologist. Failures that occur typically impact operations and can be costly to repair. Failures near streams and channel crossings have an added risk of impact to water quality. Road Slope See figure LG- 1 . All roads should be designed with one of the following three slope types: • Out-sloped roads minimize the concentration of water and minimize road width by avoiding the need for an inside ditch, but nay require roadway surface and fill slope stabilization. Out-sloped roads with clay rich, slippery road surface materials often require surface stabilization with gravel or limited use during rainy periods to assure traffic safety. On road grades over 10 to 12 percent and on steep hill slope areas, out-sloped roads are difficult to drain and can feel unsafe. • In-sloped roads are the best method to control surface water. However, in-sloped roads also concentrate water and require a system of ditches and turnouts or cross draining culverts. • Crowned roads are appropriate for higher standard, two lane roads on gentle grades. They may or may not require roadside ditches, turnouts, and/or cross drains. It is difficult to create and maintain a crown on a narrow road, so generally in-sloped or out-sloped road drainage is more effective. Construction Specifications Cut and fill Slopes • All areas to be disturbed (both cut and fill) shall be cleared, grubbed, and stripped of topsoil to remove trees, vegetation, roots, or other objectionable material . 37 • Fill material shall be free of brush, logs, stumps, roots, or other objectionable material that would interfere with, or prevent construction or satisfactory fills. This material can be set aside and later used at the toe of fill slopes as filter berms. • Table LG- 1 presents a range of commonly used cut and fill slope ratios appropriate for the soil and rock types described. Figures LG-2 and LG-3 present typical cut and fill slope design options for varying slope and site conditions. Vertical cut slopes should not be used unless the cut is in rock or very well cemented soil. Ideally, both cut and fill slopes should be constructed with a 2: 1 or flatter slope to promote growth of vegetation, but cut slopes in dense, sterile soils or rocky material are often difficult to vegetate. • All fills shall be compacted as requires to reduce erosion, slippage, settlement, subsidence, or other related problems. • Topsoil required for the establishment of vegetation shall be stockpiled in the amount necessary to complete finished grading of all exposed areas. Areas that are to be top-soiled shall be scarified to a minimum depth of four inches prior to placement of topsoil. Road Slope • See figure LG- 1 . Compact soil or road base material to direct runoff. • If crowning a road, runoff is directed to both sides of the road requiring two roadside ditches, unless runoff will drain directly to well stabilized areas. • If using an in-slope design, runoff will be directed toward the hillside and requires a roadside ditch with periodic turnouts or cross drain culvert installation. • If using an outslope design, ensure a moderate road slope with dense vegetative cover Surface Gravel • Ideally, aggregate surfacing material is (1) hard, durable, and crushed or screened to a minus 2 inch size; (2) well graded to achieve maximum density; (3) contains 5-15% clayey binder to prevent raveling; and (4) had a plasticity index of 2 to 10. • Gravel should be placed to a thickness of at least twice the diameter of the largest stone with a minimum thickness of four inches. Over very weak soils gravel thickness can be reduced with the use of geotextile or geogrid subgrade reinforcement. Also, geotextile layers are useful over soft soils to separate the gravel from the soil, keep it uncontaminated, and extend the useful life of the gravel. 38 • Compact the aggregate during construction and maintenance to achieve a dense, smooth surface and thus reduce the amount of water that can soak into the road or well pad. • "Spot" stabilize local wet areas and soft areas with four to six inches of coarse rocky material, add more as needed. • Blend coarse aggregate and fine clay-rich soil (when available) to produce a desirable composite roadway material that is coarse yet well graded with 5- 15% fines for binder. M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Inspect cut and fill slopes for rills or other indications of erosion. Maintain all crowns, out-slopes, in-slopes, and surface gravel. References Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDESy. Construction Ste Storm Water Runoff Control. Washington, D.C., February 2003 . http://cfpud.epa.gov/npdes/stormwater/menufbmps/con_site.cfm Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization (RAPPS7 of Oil and Gas Construction Stes April 2004. Keller, Gordon and James Sherar, Low-Volume Roads Engineering, Best Management Practices Field Guide. United States Department of Agriculture (USDA), Forest Service, US Agency od International Development (USAID), 2005. http://www.blm.gov/bmp/field%20guide.htm New York State Department of Environmental Conservation, New York Guidelinesfor Urban Erosion and Sediment Control. New York. Forth Edition, 1997. http://www.dec.state.ny.us/website/dow/toolbox/escstandards LG-1 Stable Slope Ratios for Various Conditions Slope Ratio Soil/Rock Condition (Hor:Vert) Most rock 1 /4: 1 to 1 /2: 1 Very well cemented soils 1/4: 1 to 1/2: 1 Most n-place soils 3/4: 1 to 1 : 1 : 1 Very fractured rock 1 : 1 to 1 1/2: 1 39 Loose coarse granular soils 1 1 /2: 1 Heavy clay soils 2: 1 to 3 : 1 Soft clay rich zones or wet seepage areas 2: 1 to 3 : 1 Fills of most soils 1 1 /2: 1 to 2: 1 Fills of hard, angular rock 1 1/3 : 1 Low cuts and fills 2: 1 or flatter (<10 ft high) (for revegetaton) Figure LG-1 Typical Road Surface Drainage Options Crown Section iyp. 4 -----► 1 I- ta • - 1;.- Outslope Section E' JI,A lY,�; • Ft TER BERM 3-646 OR OTHER2 'YD. - - . r f.( SEDIMENT CONTROL �t . te-41'l.' \ • • Inslope with Ditch Section ROADStie c$TCH 1 typo ! : .: • 2 In. 3-5% i • • NOT 1O SCALE ,.... .. . . . t 40 Paved & Graveled Vehide Tracking Control ( PGVTC) Description: CONCRETE STRUCTURE WITH GRAVEL AND CATTLE GUARD A stabilized construction entrance (tracking pad) is a pad of gravel or cattle guard where construction traffic leaves a site. The purpose of a paved and graveled entrance to a site is to minimize the amount of tracked mud and dust that leaves a site. As a vehicle drives over the pavement and gravel, mud and sediment are removed from the vehicle's wheels when crossing the cattle guards and offsite transport of soil is reduced. The paved and graveled pad also reduces erosion and rutting in the soil beneath the stabilized structure. Applicability Stabilized construction entrances are installed at locations where construction traffic leaves or enters an existing paved road. Limitations • Although stabilizing a construction entrance is a good way to help reduce the amount of sediment leaving a site, some soil may still be deposited from vehicle tires onto paved surfaces. To further reduce the chance of these sediments polluting storm water runoff, sweeping of the paved area adjacent to the stabilized site entrance is recommended. M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Visual evidence of deterioration should be repaired immediately. 41 1 I I I I 1 1 1 I 1 1 , 1 1 I , 1 I I 1 1 I 1 1 1 I 1 1 I 1 I I 1 1 1 IRIMIT4•00•••••••..W•••••MOOMOSSalletissontemenimmes t1 .o•.•. .'.•'.'••..'•••.•.•.'•.mossonsainmnt.��•laso ••••�••••••• eamsrisonsamosflennerapottaine ��rr.....*.r. or••i s��arw��r�ier��r�tens�`r��rr1•��n teet��t��rfretri°�j��r��1:��rrr��to ��i�i�iir�i��ts i�+�i�t��i�i'i'i�'��- - -�'� �� 'i � itr�i� �s ires�i��ti�i�i�r�%-��r��e'..'. �� i�i�i�s ��iei�i ��!��• �rr�te`rr�i�r�rrr�'rtorrrrrr'rrrrrrrrtrrr inert I I I I I 42 I I I I I I I I I I I I I I I I � I I I I I I f l I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I l I 1 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I ' I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 1 1 I I I I I I I I I I OOOOOOOOOOOOO 0 0 I 0 0 0 0 n 0 od 43 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I ' I I I I I I I I I I I I I I I II I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I II I I I I I I I I I I I I I I I I I l I I I I I I I I I I I I I II I I I I I I I I I I I I I I I I I I I I 1 1 I I I I I I I I I I � I I I I I I I I I I I I I I I I I I I I I I I I I l I I I I I I I I 00000000000000c O 0 I I O O L ) ( ) ( _y 0 C C 0 C ) 44 Paved Vehide Tracking Control ( PVTC) Description CONCRETE STRUCTURE WITH CATTLE GUARD A stabilized construction entrance (tracking pad) is a pad of gravel or cattle guard where construction traffic leave a site. The purpose of a paved entrance to a site is to minimize the amount of tracked mud and dust that leaves a site. As a vehicle drives over the pavement, mud and sediment are removed from the vehicle's wheels when crossing the cattle guards and offsite transport of soil is reduced. The paved pad also reduces erosion and rutting in the soil beneath the stabilized structure. Sub-surface concrete boxes exist below each cattle guard crossing to trap sediment released from vehicle tires. Applicability Typically, stabilized construction entrances are installed at locations where construction traffic leaves or enters an existing paved road. However, the applicability of site entrance stabilization should be extended to any roadway or entrance where vehicles will access or leave the site. Limitations • Although stabilizing a construction entrance is a good way to help reduce the amount of sediment leaving a site, some soil may still be deposited from vehicle tires onto paved surfaces. To further reduce the chance of these sediments polluting storm water runoff, sweeping of the paved area adjacent to the stabilized site entrance is recommended. • Site traps or other secondary sediment controls are needed to capture that sediment that accumulates at the pad and may run off during storm events. M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Sub-surface concrete boxes should be inspected for evidence of sediment deposition and cleanout should be recommended at appropriate times. Visual evidence of deterioration should be repaired immediately. 45 46 \ lit: 47 48 Revegetation ( RV) Description Revegetation involves planting seed to establish a vegetative cover in disturbed areas. Revegetation reduces erosion and sediment by stabilizing disturbed areas in a manner that is economical, adaptable to site conditions, and allows selection of the most appropriate plant material. Revegatation also: • Absorbs the impact of raindrops. • Reduces the velocity of runoff • Reduces runoff volumes by increasing water percolation into the soil. • Binds soil with roots. • Protects soil form wind. • Improves wildlife habitat. • Enhances natural beauty. Applicability Revegetation is most effective on slopes no steeper than 2: 1 . Revegetation may be used as a permanent control or a temporary control in areas where exposed soil surfaces are not to be regarded for periods longer than 30 days. Such areas include denuded areas, soil stockpiles, berms, temporary road banks, etc. Limitations The effectiveness of revegetation can be due to the following: • High erosion potential during establishment. 49 • The need for stable soil temperature and soil moisture content during germination and early growth. • The need to reseed areas that fail to establish. • Limited seeding times depending on the season. • Proper seedbed preparation and the use of quality seed are important in this practice. Failure to carefully follow sound agronomic recommendations will often result in an inadequate stand of vegetation that provides little or no erosion control. • Seeding does not immediately stabilize soils. Prior to seeding, install necessary erosion and sediment control practices such as diversions, straw bales, and basins until vegetation is established. Design Criteria Successful plant establishment can be maximized with proper planning; consideration of soil characteristics; selection of plant materials that are suitable for the site; adequate seedbed preparation, liming, and fertilization; timely planting; and regular maintenance. When to seed Areas to be stabilized with vegetation must be seeded or planted one to four months after grading is completed unless temporary stabilization measures are in place. Possible dates for seeding are as follows: Seed Mix Climate, soils, and topography are major factors that dictate the suitability of plants for a particular site. Vegetation that is adapted to the site, has strong roots, and provides good ground cover should be used. Although a native need mix is best some grasses, such as Vetiver, have been used extensively worldwide because of their strong, deep roots, adaptability, and non- invasive properties. Construction Specifications 1 . Seeding does not immediately stabilize soils. Temporary erosion and sediment control measures should be in place o prevent off-site transport of sediments from disturbed areas until vegetation is established. 2. Vegetation should not be established on slopes that are unsuitable due to inappropriate soil texture, poor internal structure or internal drainage, volume of overland flow, or excessive steepness, until measures haven taken to correct these problems. 50 3 . If the area has been recently loosened or disturbed, no further roughening is required. When the area is compacted, crusted, or hardened, the soil surface shall be loosened by disking, raking, harrowing, or other acceptable means to ensure good water infiltration and root penetration (see SURFACE ROUGHENING [SR]). 4. The soil on a disturbed site may need to be modified to provide an optimum environment for seed germination and seedling growth. To maintain a good stand of vegetation, the soil must meet certain minimum requirements as a growth medium. If any of the below criteria cannot be met then topsoil shall be applied. The existing soil must have these characteristics: • Enough fine-grained material to maintain adequate moisture and nutrient supply. • Sufficient depth of soil to provide an adequate root zone. The depth to rock or impermeable layers such as hardpans shall be 12 inches or more, except on slopes steeper than 2: 1 where the addition of soil is not feasible. • A favorable pH range for plant growth. If the soil is so acidic that a pH range of 6.0-7.0 cannot be attained by addition of ph-modifying materials, then the soil is considered an unsuitable environment for plant roots and further soil modification would be required. • Freedom from toxic amounts of materials harmful to plant growth. • Freedom from excessive quantities of roots, branches, large stones, large clods, earth, or trash of any kind. Clods and stones may be left on slopes steeper than 3: 1 if they do not significantly impede good seed soil contact. 5. Add fertilizer and/or lime, if necessary. Lime and fertilizer may be incorporated into the top two to four inches of the soil if possible. The addition of lime is equally as important as applying fertilizer. Lime will modify the pH and supply calcium and magnesium. Its effect on pH makes other nutrients more available to the plant. 6. The appropriate seed shall be evenly applied with a broadcast seeder, drill, cultipacker seeder or hydroseeder. Seeding depth should be 'A to V2 inch. 7. If necessary, apply mulch according to MULCHING (M). the mulch will hold moisture and modify temperature extremes, and prevent erosion while seedlings are growing. M aintenance Considerations 51 The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Vegetation is considered established when a density of at least 70 percent of pre- disturbance levels has been reached. Seeded areas should be inspected for failure and any necessary repairs and re-seedings should be made within the same season if possible. References Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES). Construction Ste Storm Water Runoff Control. Washington, D.C., February 2003 . http://cfpud.epa.gov/npdes/stormwater/menufbmps/con_site.cfm Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization (RAPPS) of Oil and Gas Construction Stes April 2004. Keller, Gordon and James Sherar, Low-Volume Roads Engineering, Best Management Practices Field Guide. United States Department of Agriculture (USDA), Forest Service, US Agency od International Development (USAID), 2005. http://www.blm.gov/bmp/field%20guide.htm 52 Roadside Ditches ( RSD ) and Turnouts (TO ) Description Roadside ditches are channels constructed parallel to roads. The ditches convey concentrated runoff of surface water from roads and surrounding areas to a stabilized outlet. Turnouts (also called wing ditches) are extensions of road side ditches. Turnouts effectively remove run- off water from the roadside ditch into well-stabilized areas before it reaches a waterway. Applicability • Roadside ditches should be used for all roads built on sloping topography and with either an inslope or a crowned design. • Ditch turnouts should be used as much as possible but their best use may be on slopes longer than 150ft or greater than 5%, as conditions allow. • Turnouts are applicable where fairly flat naturally vegetative areas exist at intervals by the roadside. Limitations • If these structures are not installed correctly they may become a source of erosion. • Road-side ditches do not necessarily filter sediment from runoff. • Turnouts should be on gradual slopes only. • Turnouts require vegetative cover or other filter at the discharge point. • Turnouts only work well if small volumes of runoff drain into the turnout. Turnouts should only receive runoff from the road and ditch surface, not from large, uphill watersheds. Design Criteria No formal design required. Construction Specifications 53 Roadside ditches 1 . Roadside ditches should be constructed with no projections of roots, stumps, rocks, or similar debris. 2. Excavate ditches along roadside to a width and depth that can handle expected flow according to figure RAD- 1 . 3. All ditches shall have uninterrupted positive grade to an outlet. Slope ditch so that water velocities do not cause excessive erosion, but no less than 0.5%. If steep slopes and high velocities exist, use check dams to slow runoff and catch sediment. 4. To control erosion and collect sediment, construct aggregate check dams according to figure CD- 1 of CHECK DAM (CD). 5 . All ditches shall convey runoff to a sediment trapping device such as a SEDIMENT TRAP (ST) or an undisturbed, well vegetated and stabilized area at non-erosive velocity. 6. If necessary, stabilize ditches with RIPRAP (R) or EROSION CONTROL BLANKET (ECB). Turnouts 1 . Use turnouts wherever possible and on undisturbed soil. 2. Turnouts should be on gradual slopes only and should slope gradually down from the bottom of the road-side ditch. 3. Angle turnout at approximately 30 degrees to the road-side ditch 4. Discharge turnout into well-vegetated area or install a secondary control such as a wattle, sediment trap, or silt fence. As a good rule of thumb, the vegetated outlet area should be a minimum of one half the size of the total drainage area draining into it. If well-vegetated outlets areas are not available, use culverts or other controls to direct runoff to a stabilized area. 5 . Space turnouts according to slope as indicated on figure TO- 1 . 6. Turnouts only work well if small volumes of runoff drain into the turnout. Turnouts should only receive runoff from the road and ditch surface, not from large, uphill watersheds. 54 M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Road ditches and turnouts should be inspected for any signs of channelization, and repaired as necessary. Structures will fail if water exists in channelized flow. Also inspect for sediment buildup at the outlet and at aggregate check dams and remove if necessary. References Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization (RAPPS) of Oil and Gas Construction 9tes April 2004. Keller, Gordon and James Sherar, Low-Volume Roads Engineering, Best Management Practices Field Guide. United States Department of Agriculture (USDA), Forest Service, US Agency od International Development (USAID), 2005. http://www.blm.gov/bmp/field%20guide.htm United States Department of the Interior and United States Department of Agriculture. Sirface Operating Standards and Guidelines for Oil and Gas Exploration and Development " Gold Book" . BLM/WO/ST-06/021 +3071 . Bureau of Land Management (BLM). Denver, Colorado. Fourth Edition, 2006. Figure RSD-1 Roadside Ditch Installation • Cat slryn! Flow •. •• r • ,,•• w -err--. .-.w �• \f� :; , „ . r, .. . • • :,• Rcedwa '‘' 1' OW.) Slnrnge Ares ,,r< ' • ` ' . tom . .? • ., `�ir..:a:.1 2 , Max. • • Stab[?,. x'Ilh simple check cams end . ri n p ur enrich b.alkct if re essary `elute: Sctsnx 9.53k to 20% to steb&ed gullet NOT TO SCA? E 55 Figure TO-1 Turnout Layout --- — %' ll.e.;cwtcJ am'yr uflr Y/t1 rcgtNled O"ss;o•nMf - - — - - - i truer turd rturnjtt. Marrs onto'anosunt) I " r ' ' I 4. V 1 V Rood Sao %treat --— 6nw3ag�tifei�asv:rut. 57 x SWAP Jl J <244 •:t-00 M 2.5% I 200 Access Road j 6.10% 100 1 • • 1 t 1 1 Will tognblS SW(o'Ott ' si.n;terta0 ilre(Ot es etoscc caltol('teen} errs M o]eltol nreeuas1 56 Silt Fence (SF) 50 X 50 WOOD STAKE TOE OF SLOPE 150 FABRIC SECTION B FABRIC STAKE B SLOPE 750 STAKE A 150 450 FABRIC SECTION A 150 SILT FENCE JOINING ROLL TO ROLL SILT FENCE INSTALLATION AT SLOPE BASE DETAIL (PLAN VIEW) GREEN SILT , FENCE FABRIC 50 X 50 WOOD STAKE 1 r 50 X 50 WOOD STAKE FABRIC \ $ XXI 150 END STAKE DETAIL ;PLAN VIEW) INSTALLATION TRENCH DETAIL (PLAN VIEW, Description Silt fences are used as temporary perimeter control around sites where there will be soil disturbance due to construction activities. They consist of a length of filter fabric stretched between anchoring post at regular intervals along the site perimeter. Applicability Silt fences are generally applicable to construction sites with relatively small drainage areas. They are appropriate in areas where runoff will be occurring as low-level shallow flow, not 57 exceeding 0.5cfs. The drainage area for silt fences generally should not exceed 0.25 acre per 100-foot fence length. Slope length above the fence should not exceed 100 feet. Limitations • Silt fence should not be installed along areas where rocks or other hard surfaces will prevent uniform anchoring of fence posts and entrenching of the filter fabric. This will greatly reduce the effectiveness of silt fencing and can create runoff channels leading offsite. • Silt fences are not suitable for areas where large amounts of concentrated runoff are likely. • Open areas where wind velocity is high may present a maintenance challenge, as high winds may accelerate deterioration of the filter fabric. • Silt fences should not be installed across streams, ditches, or waterways. • When the pores of the fence fabric become clogged with sediment, pools of water are likely to form on the uphill side of the fence. Location and design of the silt fence should account for this and care should be taken to avoid un-necessary diversion of storm water from these pools that might cause further erosion damage. Design Criteria The fence should be designed to withstand the runoff from a 10-year storm event. Construction Specifications 1 . Erect silt fence according to figure SF- 1 . 2. If standard strength fabric is used in combination with wire mesh, the support posts should be spaced no more than 10 feet apart. If extra-strength fabric is used without wire mesh reinforcement, the support posts should be spaced no more than 6 feet apart. 3. Stakes used to anchor the filter fabric should either be wooden or metal. Wooden stakes should be at least three feet tall and have a minimum diameter of two inches if a hardwood such as oak is used. Softer woods such as pine should be at least four inches in diameter. When using metal post in place of wooden stakes, they should have a minimum weight of 1 to 1 .331b/linear foot. If metals post are used, attachment points are needed for fastening the filter fabric using wire ties. The height of the fence post should be between 16 and 34 inches above the original ground surface. 58 4. Material for silt fences should be a pervious sheet of synthetic fiber such as polypropylene, nylon, polyester, or polyethylene yarn, chosen based on minimum synthetic fabric requirements, as shown in the following table: Ph sical Pro Ra uirements Filtering Efficiency 75 — 85% (minimum): highly de ndent on local conditions Tensile Strength at 20% Standard-Strength: 30 Ibs./linear inch (maximum) Elongation (minimum) Extra Strength- 50 lbs/linear inch (minimum) Ultraviolet Radiation _ 90% (minimum) Slurry Flow Rate _ 0.3 We/min minimum 5. Use a continuous roll of fabric to eliminate unwanted gaps in the fence. If a continuous roll of fabric is not available, the fabric should overlap from both directions only at the stakes or posts with a minimum overlap of six inches. 6. Extend silt fence across grade and upslope for a short distance. 7. Compact backfill at base of fabric. 8. Plow in or entrench the bottom of the fabric fence at least 6 inches below the ground surface. This will help prevent gaps from forming near the ground surface that would render the fencing useless as a sediment bather. M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Inspect silt fences to ensure that they are intact and that there are no gaps at the fence- ground interface or tears along the length of the fence. If gaps or tears which impact the effectiveness of the silt fence are discovered, they should be repaired or the fabric should be replaced immediately. Accumulated sediments should be removed from the fence base when the sediment reaches 1/3 to 1/2 the height of the fence. Sediment removal should occur more frequently if accumulated sediment is creating noticeable strain on the fabric and there is the possibility of the fence failing from a sudden storm event. Removal Remove silt fences and all accumulated sediment after uphill drainage areas are stabilized by vegetation or other means. References 59 Colorado Department of Transportation (CDOT), Erosion Control and Sormwater Quality Guide. 2002. http://ww.dot.state.co.us/enviromental.envWaterQual/wgms4.asp Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES). Construction Ste Storm Water Runoff Control. Washington, D.C., February 2003 . Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization (RAPPS) of Oil and Gas Construction Stes April 2004. Keller, Gordon and James Sherar, Low-Volume Roads Engineering, Best Management Practices Field Guide. United States Department of Agriculture (USDA), Forest Service, US Agency od International Development (USAID), 2005. http://www.blm.gov/bmp/field%20guide.htm 60 Straw Bale (SB) - Straw Bale Placement in Swale (SBS) t 4 ' /J AY\ BALE WIDTH 18" TYP TRENCH EXCAVATION 2"X2"X24" ji36" TYP. STAKE (MIN) 1 ` t bN4 adr BACKFILL AND COMPACTED EXCAVATED TRENCH SOIL •.��=" h ,t.,. . '' _ Ji ;� $<c BINDING WIRE I�=lid... OR OR TWINE t �^� .7,.. // I�II!✓I ' STRAW BALE INSTALLATION 18" P. TY 2"X2"X24" yy jj l!tt11�{ 44 STAKE (MIN) ii� Illl 4" M I N 18" TYP. FLOW - . . \ . ►i , , V I`. a i — i . � �-i I' '~t' i IL ,. BACKFILL AND COMPACT EXCAVATED TRENCH SOIL SECTION C-II-T S B --) I I IC)* STRAW BALE 61 END POINTS "A" MUST BE HIGHER THAN POINT "B" STRAW BALES SHALL NOT BE USED IN A A CHANNELS/SWALES LESS THAN 3.0' IN -...„ B DEPTH. CONTRACTOR SHALL INSTALL ROCK �1 - �� 11- SOCK RSS IN ALL CHANNELS/SWALES LESS / 11. THAN 3.0' IN DEPTH. .11=11=11=n'' - =11=11- 11=11=11=II= II=I1= . . a Z STRAW BALE IN SWALES SECTION STRAW BALES MUST BE TIGHTLY ABUTTING ONE OR MORE BALES IN WITH NO GAPS CHANNEL BED TIGHTLY ABUTTING EACH OTHER t l Ib o�i1 iii � � Ir -� � _�' �i L = THE DISTANCE SUCH THAT POINT D AND C ARE OF EQUAL ELEVATION. 1 STRAW BALE DOWNSTREAM SPACING r Co _--.m -r r 4 I1-I'I I ' ,_-,7- ,-,-1 rl 1 1-1 1-_j_-1-1U STRAW BALE IN SWALES SECTION LI_I_I_- it t i- SBS STRAW BALE PLACEMENT IN SWALE 62 Straw Bale I nstallation Notes STRAW BALES SHALL CONSISI OF CERTIFIED WEED FREE STRAW OR HAY CERTIFIED UNDER THE COLORADO DEPARTMENT OF AGRICULTURE WEED FREE FORAGE CERTIFICATION PROGRAM AND INSPECTED AS REGULATED BY THE WEED FREE FORAGE ACT, TITLE 35, ARTICLE 27. 5, CRS. EACH CERTIFIED WEED FREE MULCH BALE SHALL BE IDENTIFIED BY ONE OF THE FOLLOWING: • ONE OF THE TIES BINDING THE BALE SHALL CONSIST OF BLUE AND ORANGE TWINE, OR • ONE OF THE TIES BINDING THE BALE SHALL CONSIST OF SPECIALLY PRODUCED GALVANIZED SHINY WIRE, OR • THE BALE SHALL HAVE A REGIONAL FORAGE CERTIFICATION PROGRAM TAG INDICATING THE REGIONAL FORAGE CERTIFICATION PROGRAM NUMBER. STRAW BALES SHALL BE INSPECTED FOR AND REGIONALLY CERTIFIED AS WEED FREE BASED ON THE REGIONALLY DESIGNATED NOXIOUS WEED AND UNDESIRABLE PLANT LIST FROM COLORADO, WYOMING, MONTANA, NEBRASKA, UTAH, IDAHO, KANSAS, SOUTH DAKOTA OR ANY OTHER STATE NOT LISTED THAT SERVED AS THE PLACE OF ORIGIN FOR THE STRAW MULCH. NO ONE SHALL UNLOAD CERTIFIED WEED FREE MULCH BALES OR REMOVE THE IDENTIFYING TWINE, WIRE OR TAGS UNTIL THE TOWN'S INSPECTOR HAS INSPECTED AND ACCEPTED THEM. THE CONTRACTOR SHALL PROVIDE A TRANSIT CERTIFICATE THAT HAS BEEN FILLED OUT AND SIGNED BY THE GROWER AND BY THE DEPARTMENT OF AGRICULTURE INSPECTOR. THE CONTRACTOR MAY OBTAIN A CURRENT LIST OF COLORADO WEED FREE FORAGE CROP PRODUCERS WHO HAVE COMPLETED CERTIFICATION BY CONTACTING THE COLORADO DEPARTMENT OF AGRICULTURE, DIVISION OF PLANT INDUSTRY. STRAW BALES SHALL BE APPROXIMATELY 5 CUBIC FEET OF MATERIAL AND WEIGH NOT LESS THAN 35 POUNDS. TYPICAL STRAW BALES SHALL BE APPROXIMATELY 36"X18"X18". A UNIFORM ANCHOR TRENCH SHALL BE EXCAVATED TO A DEPTH OF 6". STRAW BALES SHALL BE PLACED SO THAT BINDING TWINE IS ENCOMPASSING THE VERTICAL SIDES OF THE BALE(S). ALL EXCAVATED SOIL SHALL BE PLACED ON THE UPHILL SIDE OF THE STRAW BALE(S) AND COMPACTED. TWO (2) WOODEN STAKES SHALL BE USED TO HOLD EACH BALE IN PLACE. WOODEN STAKES SHALL BE 2"X2"X24". WOODEN STAKES SHALL BE PLACED 6" INTO THE GROUND. STRAW BALES SHALL BE SPACED AND POSITIONED ACCORDING TO DETAILS. 63 Straw Bale I nstallation & M aintenanve Notes THE EROSION CONTROL SUPERVISOR SHALL INSPECT HE STRAW BALES AT THE FOLLOWING INTERVALS: • IMMEDIATELY FOLLOWING INITIAL INSTALLATION. • EVERY 14 DAYS WHILE THE SITE IS UNDER ACTIVE CONSTRUCTION. • AFTER ANY STORM EVENT THAT CAUSES SOIL EROSION. • ONCE A MONTH FOLLOWING THE END OF CONSTRUCTION, UNTIL VEGETATIVE COVER HAS REACHED A CONSISTENT DENSITY OF AT LEAST 70% OF FULL VEGETATIVE COVER. ACCUMULATED SEDIMENT SHALL BE REMOVED ONCE THE SEDIMENT HAS REACHED A DEPTH EQUAL TO 1 /4 THE HEIGHT OF THE STRAW BALE. STRAW BALES SHALL BE REPLACED IF THEY BECOME HEAVILY SOILED, ROTTEN, OR OTHER DAMAGES. STRAW BALES SHALL REMAIN IN PLACE AND PROPERLY MAINTAINED UNTIL VEGETATIVE COVER HAS REACHED A CONSISTENT DENSITY OF AT LEAST 7O% OF FULL VEGETATIVE COVER AND EROSION AND SEDIMENTATION IS NO LONGER A POSSIBILITY AS DETERMINED BY THE TOWN'S INSPECTOR. WHEN THE STRAW BALES ARE REMOVED, ANY DISTURBED AREAS ASSOCIATED WITH THE INSTALLATION, MAINTENANCE, AND/OR REMOVAL OF THE STRAW BALES SHALL BE ROUGHENED, SEEDED, MULCHED, AND CRIMPED PER THE TOWN'S SPECIFICATIONS (SEE DETAIL SMC). 64 Straw Mulch (SM ) r - \I" re i '8\ Description and Purpose Straw mulch consists of placing a uniform layer of straw and incorporating it into the soil with a studded roller or anchoring it with a tackifier stabilizing emulsion. Straw mulch protects the soil surface from the impact of rain drops, preventing soil particles from becoming dislodged. Suitable Applications Straw mulch is suitable for soil disturbed areas requiring temporary protection until permanent stabilization is established. Straw mulch is typically used for erosion control on disturbed areas until soils can be prepared for permanent vegetation. Straw mulch is also used in combination with temporary and/or permanent seeding strategies to enhance plant establishment. 65 Limitations • Availability of straw and straw blowing equipment may be limited just prior to the rainy season and prior to storms due to high demand. • There is a potential for introduction of weed seed and unwanted plant material. • When straw blowers are used to apply straw mulch, the treatment areas must be within 15O ft of a road or surface capable of supporting trucks. • Straw mulch applied by hand is more time intensive and potentially costly. • Wind may limit application of straw and blow straw into undesired locations. • May have to be removed prior to permanent seeding or prior to further earthwork. • "Punching" of straw does not work in sandy soils, necessitating the use of tackifiers. Implementation • Straw shall be derived from wheat, rice, or barley. Where required by the plans, specifications, permits, or environmental documents, native grass straw shall be used. • A tackifier is the preferred method for anchoring straw mulch to the soil on slopes. • Crimping, punch roller-type rollers, or track walking may also be used to incorporate straw mulch into the soil on slopes. Track walking shall only be used where other methods are impractical. • Avoid placing straw onto roads, sidewalks, drainage channels, sound walls, existing vegetation, etc. • Straw mulch with tackifier shall not be applied during or immediately before rainfall. • In San Diego, use of straw near wood framed home construction has been frowned on by the Fire Marshall. 66 Application Procedures ■ Apply straw at a minimum rate of 4,000 lb/acre, either by machine or by hand distribution. • Roughen embankments and fill rills before placing the straw mulch by rolling with a crimping or punching type roller or by track walking. • Evenly distribute straw mulch on the soil surface. • Anchor straw mulch to the soil surface by "punching" it into the soil mechanically (incorporating). Alternatively. use a tackifier to adhere straw fibers. ■ Methods for holding the straw mulch in place depend upon the slope steepness, accessibility, soil conditions, and longevity. - On small areas. a spade or shovel can be used to punch in straw mulch. - On slopes with soils that are stable enough and of sufficient gradient to safely support construction equipment without contributing to compaction and instability problems, straw can be "punched" into the ground using a knife blade roller or a straight bladed coulter, known commercially as a "crimper". - On small areas and/or steep slopes, straw can also be held in place using plastic netting or jute. The netting shall be held in place using 11 gauge wire staples, geotextile pins or wooden stakes as described in EC-7, Geotextiles and Mats. - A tackifier acts to glue the straw fibers together and to the soil surface. The tackifier shall be selected based on longevity and ability to hold the fibers in place. A tackifier is 67 typically applied at a rate of 1251b/acre. In windy conditions, the rates are typically 18o lb/acre. Costs Average annual cost for installation and maintenance (3-4 months useful life) is S2,500 per acre. Application by hand is more time intensive and potentially costly. Inspection and Maintenance • Inspect BMPs prior to forecast rain, daily during extended rain events, after rain events, weekly during the rainy season, and at two-week intervals during the non-rainy season. • Areas where erosion is evident should be repaired and BMPs re-applied as soon as possible. Care should be exercised to minimize the damage to protected areas while making repairs, as any area damaged will require re-application of BMPs. • The key consideration in inspection and maintenance is that the straw needs to last long enough to achieve erosion control objectives. • Maintain an unbroken, temporary mulched ground cover while disturbed soil areas are inactive. Repair any damaged ground cover and re-mulch exposed areas. • Reapplication of straw mulch and tackifier may be required to maintain effective soil stabilization over disturbed areas and slopes. References Controlling Erosion of Construction Sites, Agricultural Information Bulletin #347. U.S. Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS) (formerly Soil Conservation Service — SCS). Guides for Erosion and Sediment Control in California. USDA Soils Conservation Service, January 1991. Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments. May 1995. Soil Erosion by Water. Agricultural Information Bulletin #513, U.S. Department of Agriculture, Soil Conservation Service. Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans). November 2000. Storm eater Management of the Puget Sound Basin, Technical Manual, Publication #91-75. Washington State Department of Ecolo&v, February 1992. Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988. 68 Vehide Tracking Control (VTC) Description CATTLE GUARD A stabilized construction entrance (tracking pad) is a pad of gravel or cattle guard where construction traffic leave a site. The purpose of a stabilized entrance to a site is to minimize the amount of tracked mud and dust that leaves a site. As a vehicle drives over the gravel pad, mud and sediment are removed from the vehicle's wheels and offsite transport of soil is reduced. The gravel pad also reduces erosion and rutting in the soil beneath the stabilized structure. The filter fabric separates the gravel from the soil below, preventing the gravel from being ground into the soil. The fabric also reduces the amount of rutting caused by vehicle tires by spreading the vehicle's weight over a larger soil area than just the width of the tire. Applicability Typically, stabilizing a construction entrances are installed at locations where construction traffic leaves or enters an existing paved road. However, the applicability of site entrance stabilization should be extended to any roadway or entrance where vehicles will access or leave the site. Limitations • Although stabilizing a construction entrance is a good way to help reduce the amount of sediment leaving a site, some soil may still be deposited from vehicle tires onto paved surfaces. To further reduce the chance of these sediments polluting storm water runoff, sweeping of the paved area adjacent to the stabilized site entrance is recommended. • Site traps or other secondary sediment controls are needed to capture that sediment that accumulates at the pad and may run off during storm events. 69 Design Criteria ROAD WIDTH AS RECLIRED PROVIDE CROWN WITH CROSSFALL ROTH WAYS FOR WIDTHS IN EXCESS OF 15' ROADSIDE DITC WHERE REQUIRED 2% S' OPE !, ),/ ,c .. II•• II � II �I�11 II 1 - II " 1 1 * L 6" LIFT CRUSHED ROCK FILTER FABRIC FOR ROADS IN USE IN EXCESS OF 1 YR. Construction Specifications See figure SCE- 1 for installation details. • If the pad in constructed on a crowned road, a road side ditch with check dams or sediment traps be located on both sides of the road to collect runoff from the pad. If the road slopes to only one side of the road then only one roadside ditch with sediment controls will be needed. • Place a matrix of 2 to 4 inch washed stone, reclaimed or recycled concrete equivalent to a minimum of 12 feet wide and 20 feet in length. • All surface water flowing or diverted toward construction entrance shall be piped across the entrance. If piping is impractical, a mountable berm with 5: 1 slopes will be permitted. 70 rtesr.7-1 Yom.r•r-v 0.-71.--17.--4__ i f r r GENERAL NOTES 7D; t _ I. a0•[nrrr :.•..i .r cMs a roulnl7o. rA. K afr-«-•lAtT w nr:..r Ir — I .. • -- / •. -.!'„y _d, : .•-.A-!F�_..�� _ ,•li y I 2.1. Drava wra mow: t w-.iwm me «o. ti y I 1 Al Non lo s. IMA'!D h Accaosz Wi' .el.ro Y If1 MO a c/• •�� . " � :in—� -�'��' \\ T r-4• c r..0 .O.la so a 11141 rIw • r IIa..O ••rK,. heal ��, i All 57eL'tIA1t sin 1Wt K fAOICA'C AK Nor= MITI AtWaM *WIT r • . �,� s— ,, \ -• ,-E . AOEwO.IKF «�•4ECI1o.I to ... •rrw1.WY 1Kwl M WOWED M ,rAD.IM«CE . « AAW10 Y II1 CO MOW NM LIC-e0'I Pe YQ1.0 «I.TI.11' 9m►U'IO« 000-r-pan —�- �•��:rte: t ♦ ou irotr 4W OM OYU 004•a!I to •r s • .p :Marro Y 77D) o.•Ot 7.. • " i —� �'r��1'II I •• , Ir 7 Iona� SwilmI•CYY4011fM 94 043 MUM wsi moo carman lIIbC��~un• COO IYL VW �K I , ' I (t a SO cues :MOO e Olt ..1174117 o 4419...0..6 W 7.011. KOL}MR 01.7.147. rl Y• i�— - •-1 :I.` I�,Y 7-P I ac t MAC= to War 00457 M®IL afar filet OM** xJt5 I I tom' _ �! r� I twl * .s Sac Co DO Kure MOP aA7011 OT II Op90AEn I_ • 1 •J/ ♦ :—S I I II` I. fwc r out (rKa w rIr<) Shia t srm +arm flaw= aav cw TIC �J• '� 'r/`• M/' ..•^ 'll` 7 - �� `�J Io ssnrrlK crww�cw «o z'Wcnwr Naw1 w. wr at Ifiu.rrz Mr. nr no 1. .. ••, 4 •••14•3;C•i. 1.)4Yl'1ir, I.Jf fW. H I.Il1gID N 11t p711 d Rt lf*,L P1N1•). (}y.,•_• •• • J• ' / ,11•\•• .. •' >f' 1�.,'• .• /\ 4•'444 "w•. WOW » TINKER WANG STEEL WINO '(.i in?II // yi o o PIO •Iry M Po r is RM I/• al.. IY DI ]YPICAL CICU GUARD I STA—t1A4JONS ir ran MAR + I. 1 I� p aanl 2 IOU am r 4W ••R AA I r 1 ra fur w7�om p/ 04110 •nyl faM i'. 7. • no a Ito q ' ' . a I Nit NSW Y'A• •••I MID ANN man ,,•Si' ` ►. re N1I fa CA RA iWR W`iII•IY • she 0. Of Ire ,` 9r ••• N• Iorlana , s, 71,47�i;4 i' yr. nil .� -N �i of owl LOOM yo `�. \ . eve ' is 0••Ul - 'wRuil7i Q'' .t. 1� ma won lan !' "I... \ l i �u1Kl OMI �I 1 t •mac- r'NM S.OfR: 1 R w Irytl• ,)� \ G4'_IN_PIACE t•ii t rJ —ti DolmPRECAST •1c cumin MIN ms ro_ oORIABU: gym, � KS 1C'• . AD 7;FOLACADAR nit")OIL CZ a• ros ,o "� r rCU1CA'I#4 ` 414 t'•RU .Z' ROADWAYS. DRILLING LAYOUT was .h' AND '6' nent)wArg ass m , yULTIPLE GRILL UNIT CONNECTION • INS If MC r. of If K If au WO i Y S IPA r•'A':.r AWN �o Mir NW K own% au metro KI.rL ooI a r- Y1 l-r !X :. . :21-% I7 17•M a r coDo-7-Y T eIr / suwlw0la•I=. 1rm sans 1K' /K. II14A 7-,w. w. w• 0070 04 Its aw.rir 1 il a . �� I f :c<.• cf. MOM r it —r r v:•r sys7r mac co .'h — l'1• a, r4 --1 'Iiirdaw IOWZ•w1 n1)']1 'C.V h'Igl�s Int. L nu cos RR I r r-SW TOW r 1YA')0S VI VJW WELDED GRILL CROSS SLCPONS SLAIN FOJNDATIOM OLANTi 1ES >r la 4Y Wan a r ms 1 119E MOST 057-N-t W E TM r. b. K.ri M WwL yr mu Ye we II�• I :• -�,'f Mai• 1�! mrJ!'t 0►.- y��I-� Mt A Cal 7 7e: F3y• A+ vrl:'th IRA tKTtPAWL) lW n•1m Do Imo ' 11 i I • ID ID w IN U IN N IAN II ,;• , . II II SA 317 li 7I. /I Im up I-I• 1 t I - N 11 74 3't II it rl 21* I MIL marl �/ fl N I I a• 44 AI Ulf N 31n -fl _— — —— --- -- — Tuve=Yl- . - - I I I R Zan .' Ii I ID 4 IC a 3434 II 1 le•a% . _�I )7I i0 t NI It .a t%.'/ 17-. inn - II N IT Ili 101 N au 1 rat i••a-4-007 Oa lryq N a u ,13 1m v IS I __ —. _ _ _ _- rjrf�I .. imam t 14 14 III P7 II NW ?a 11 14 1 AI N t9 �� - ��--, iLEA .I i. I AD IA II 191 M ,1 AN rr L701AM1 MI5 EtIN/IR AD IA II N it M 71 AN ROY AID 1111 LIE IA1EM.• %MEN Wt.It OW 10 3I II*a MS 710 N 1707 II )711 Ar VOIR AID 7I It II II 44 IN II 010. AA -it> I it I tr >r�a 1 -f^T -I ,'I ld ROI 7E� MOI 3 1411 14 113 PI T* O 14 1I U Ni Ka N Tu- mrrmr!Oi a 1414 14 Ml W. u Aux 1 - F. WELDED GRILL WING OUANTiTIE5 tlit'JifI Kml93fOIl4931I Al ., tea fA.•4NH UN TS ONE MOD MC GNr an a ELEVATION OF FOUNDA1,On - MO . r. r . r-r • r . r • S.• . sr) a ONO b r.r . r-04. . r . r . Pr . sr a1. r ON . r.r • r-r . r . r . W . Or lr SO 4 r.r • r-r • 04•• %W. Se•••M'\ a' um • r.r • r-r • I WmtIf• IV•s•S\/ r r K 1740 I r•r • r-r IS • I '• INe. X•..r ma r.r • .•r• I I II�•. tic.. 3 .1 T r. r • r-r 1 r . r • Y.• • tM ill a .w Wien_ TAD t. le. I.'.SOS US r r Inc -'. r- 1MD ou if., w: ?:«rJ - 71A r7' I I r . r . rte'NMI Ian -- UN At•• 1w ' • it I i—I a I I —le ii r.•- 1 iI 1 . -).4. 'WI .1,.n,• L —:rife.99.11-041,_Y1 1L _ V. .II. (Thb 71c .a END SECTION OF L L_ -` -- FOUNDATION lai5 E , r - L .I. ,• IOW IOW Ir I ,r---I l- ,- r 4K• SECTION A—A END SECTION I ATITPAI CI Ioonu ELEVATION OF LATERAL SUPPORT 71 M aintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Stabilization of site entrances should be maintained until the remainder of the construction site has been fully stabilized. Stone and grave; might need to be periodically added to each stabilized construction site entrance to keep the entrance effective. Soil that is tracked offsite should be swept op immediately for proper disposal. References Colorado Department of Transportation (CDOT), Erosion Control and Stormwater Quality Guide. 2002. http://ww.dot.state.co.us/enviromental.envWaterQual/wgms4.asp Environmental Protection Agency (EPA), National Pollutant Discharge Elimination System (NPDES). Construction Ste Storm Water Runoff Control. Washington, D.C., February 2003 . http://cfpud.epa.gov/npdes/stonnwater/menufbmps/con site.cfm Horizon Environmental Services, Inc, Guidance Document Reasonable and Prudent Practices for Stabilization (RAPPS) of Oil and Gas Construction Stes April 2004. 72 Wattles (W ) Description A wattle, (consist of straw, rock, flax, or other similar materials bound into a tight tubular roll. When wattles are placed at the toe and on the face of slopes, they intercept runoff, reduce its flow velocity, release the runoff as sheet flow, and provide removal of sediment from the runoff By interrupting the length of a slope, fiber rolls can also reduce erosion. Applicability Wattles may be suitable: • Along the top, face, and at the grade breaks of exposed and erodible slopes to shorten slope length and spread runoff as sheet flow. • At the end of a downward slope where it transitions to a steeper slope. • Along the perimeter of a project. • At the overflow locations of s sediment traps. • As check darns in unlined ditches. • Around temporary stockpiles. Limitations • Wattles are not effective unless trenched. • Wattles at the toe of the slope greater than 5: 1 (H:V) should be a minimum of 20 inch diameter or installations achieving the same protection (i.e., stacked smaller diameter wattles, etc.). • Difficult to move once saturated. • If not properly staked and trenched in, wattles could be transported in high flows. • Wattles have a very limited sediment capture zone. • Wattles should not be used on sloped subject to creep, slumping, or landslide. 73 • Wattles should not be used where periodic road or surface maintenance activities are expected. Design Criteria }. 1 , l ./ il I B / B Mad Ix II ! Dr•Dirm r 0 ' �lTJAI- trrw,tr a ,~ 1 11 r as" Ino - --- a 11 I �� I /1 MUM M SECTION a-9 a a SOW, LOG PUN VIEW a 7+Mc WM z I Ig . I 17�. I r a Ilk ao➢aI IX nec a MMLS oaaw9t ��• nmrc Cut VFRT EROSION LOG 1NaET PROTECITh Ms SINE Mr 24 kMO XIfl ID Mnw n ONMINM P10.00.t Vii •: �' "1°.I _ -- PE UMW Cr Pt ooaab we PLAN_YIER 1/1 . 11 l ifit l J 1 til11,9/ /11/14 ri/l illii RIO 0 .____ I/// L-1 iir� D D/ ..... rc�fi.oa a a.nl[ l, _____ :-=: - �� ran J = MIA 24s w .ms c�cra I / , . ?;,. 111�`l.l' fi'��'l��llir�,'l %�iri�I�i moo. r- E ,.',Ili: PUN VIEW mas too BALM SECTION A—A ^m.criarfi1 Ott Ott , MIT* 111 IVrr A TERCSIOh LOG APPLICAT ION 4N AND '-----.114. — �T . . ... ... .. % \TofPErlbf Y uaffx� r ,/!i\ \ \\%/\i\\+oi 1'115 A rC II CO IS Pa/! SW VW U Do9o.f rat V W at fic crCp .N D—Q 0 OUMWIHEWI tat t rERIN -, .,'1 Aft M wtlar tHXlf 1f'a}I &aluv urn Pan rjcIcs LOG DETAIL DROP INLET EDITCH NINSTALLATION EROSCN LOG Ell TER Construction Specifications Wattles should be either prefabricated rolls or rolled tubes of erosion control blankets. If using erosion control blankets, roll the length of erosion control blanket, roll the length of the blanket into a tube of minimum 8" diameter and bind roll at each end and every 4 feet along length of roll with jute type twine. See figure W- 1 for wattles used to control erosion along slopes. 1 . Locate wattles on level contours spaced as follows: a. Slope inclination of 4: 1 or flatter: Fiber rolls should be placed at a maximum interval of 20 feet. b. Slope inclination between 4: 1 and 2: 1 : Fiber rolls should be placed at a maximum of 15 feet. 74 c. Slope inclination 2: 1 or greater: Fiber rolls should be placed at a maximum interval of 10 feet. 2. Turn the ends of the wattles up slope to prevent runoff from going around the roll. 3 . Stake wattles into a 2 to 4 inch deep trench with a width equal to the diameter of the wattle. Drive stakes at the end of each wattle and spaced 4 feet maximum on center. 4. If more than one wattle is placed in a row, the rolls should be overlapped, not abutted. Maintenance Considerations The frequency of inspections should be in accordance with the Storm Water Management Plan (SWMP). Repair or replace split, torn, unraveling, or slumping rolls. If the wattle is used as a sediment capture device, or as an erosion control device to maintain sheet flows, sediment that accumulates must be periodically removed in order to maintain wattle effectiveness. Sediment should be removed when sediment accumulation reaches half the distance between the top of the wattle and the adjacent ground surface. Removal Wattles are typically left in place. If wattles are removed, collect and disposed of sediment accumulation, and fill and compact holes, trenches, depressions, or any other gorund disturbance to blend with adjacent ground. References California Stormwater Quality Association, Stormwater Best Management Practices(BMP) handbook-Construction. January, 2003 . <http://www.cabmphandbooks.com/Construction.asp> 75 Wind Erosion Control (WEC) ilF1=0 ill - r- /7 1•I 1-/ Description and Purpose Wind erosion or dust control consists of applying water or other dust palliatives as necessary to prevent or alleviate dust nuisance generated by construction activities. Covering small stockpiles or areas is an alternative to applying water or other dust palliatives. Suitable Applications Wind erosion controls BMPs are suitable during the following construction activities: • Construction vehicle traffic on unpaved roads • Drilling and blasting activities • Sediment tracking onto paved roads • Soils and debris storage piles • Batch drop from front-end loaders • Areas with unstabilized soil 76 • Final grading/site stabilization Limitations • Watering prevents dust only for a short period and should be applied daily (or more often) to be effective. • Over watering may cause erosion. • Oil or oil-treated sub grade should not be used for dust control because the oil may migrate into drainageways and/or seep into the soil. • Effectiveness depends on soil, temperature, humidity, and wind velocity. • Chemically treated sub grades may make the soil water repellant, interfering with long- term infiltration and the vegetation/re-vegetation on the site. Some chemical dust suppressants may be subject to freezing and may contain solvents and should be handled properly. • Asphalt, as a mulch tack or chemical mulch, requires a 24-hour curing time to avoid adherence to equipment, worker shoes, etc. Application should be limited because asphalt surfacing may eventually migrate into the drainage system. • In compacted areas, watering and other liquid dust control measures may wash sediment or other constituents into the drainage system. I mplementation General Recently, the State Air Resources Control Board has, under the authority of the Clean Air Act, started to address air quality in relation to inhalable particulate matter less than 10 microns (PM- 10). Approximately 90 percent of these small particles are considered to be dust. Existing dust control regulations by local agencies, municipal departments, public works department, and public health departments are in place in some regions within California. Many local agencies require dust control in order to comply with local nuisance laws, opacity laws (visibility impairment) and the requirements of the Clean Air Act. The following are measures that local agencies may have already implemented as requirements for dust control from contractors: • Construction and Grading Permits: Require provision for dust control plants. • Opacity Emission Limits: Enforce compliance with Colorado air pollution control laws. 77 • Increase Overall Enforcement Activities: Priority given to cases involving citizen complaints. • Maintain Field Application Records: Require records of dust control measures from contractor; • Stormwater Management Plan (SWMP): Integrate dust control measures into SWMP. Dust Control Practices Dust control BMPs generally stabilize exposed surfaces and minimize activities that suspend or track dust particles. For heavily traveled and disturbed areas, wet suppression (watering), chemical dust suppression, gravel asphalt surfacing, temporary gravel construction entrances, equipment wash-out areas, and haul truck covers can be employed as dust control applications. Permanent or temporary vegetation and mulching can be employed for areas of occasional or no construction traffic. Preventive measures would include minimizing surface areas to be disturbed, limiting onsite vehicle traffic to 15 mph, and controlling the number and activity of vehicles on a site at any given time. For chemical stabilization, there are many products available for chemically stabilizing gravel roadways and stockpiles. If chemical stabilization is used, the chemicals should not create any adverse effects on stormwater, plant life, or groundwater. Costs Installation costs for water and chemical dust suppression are low, but annual costs may be quite high since these measures are effective for only a few hours to a few days. I nspection and M aintenance • Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect weekly during the rainy season and at two-week intervals in the non-rainy season to verify continued BMP implementation. • Check areas protected to ensure coverage. • Most dust control measures require frequent, often daily, or multiple times per day attention. 78 APPENDIX D TRAINING LOG Bonanza Creek Energy Operating Company, LLC Stormwater Training Log Name: Course Completion Date: 4 Signature: Hello