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HomeMy WebLinkAbout20112963 e � , Z � , , MEMORANDUM TO: Tom Parko, Planning Services DATE: November 14, 2011 FROM: Clay Kimmi, P.E., CFM WEL O NTY SUBJECT: USR11-0013, Steve Sharp Transportation Water Quality Calcs The Weld County Public Works Department reviewed the submitted application for critical items, including but not limited to Site Plan, Traffic Study, Preliminary Drainage Report, Geotechnical Soils Report, and Flood Hazard Development Permit. All issues of concern and critical issues during further review must be resolved with the Public Works Department. COMMENTS: The applicant's engineer submitted the water quality calculations for review on November 10, 2011. The required volume needed for the water quality control feature is 13,237 cubic feet. The applicant is showing a water quality feature that is sufficiently sized. NOV 1 5 2011 • Weld Co:.:, • EXHIBIT • I D s. —Aka Page 1 of 1 v1 d� ""/A M:\PLANNING-DEVELOPMENT REVIEW\-2011 Planning Referrals\USR11\USR11-0013 Sharp Transportation\USR11-0013 Water Quality Calcs 11- 14-11.docx Reams& Patterson Inc. r 1 consulting Engineers and Land Surveyors HP !h I'/ [7` f 7 ' 950 South Jamaica Court, Suite 305 Aurora, Colorado 80014 j 303-745.4747 L L NOV 1 0 9011 November 10, 2011 WELD COHNITPUBLIC VdOnKS DFPT Mr. Clay Kimmi, PE WELD COUNTY DEPARTMENT OF PUBLIC WORKS 1111 H Street Greeley, CO 80632 Re: STEVE SHARP TRANSPORTATION, CR 41 at CR 24 Recorded Exemption No. 1307-09-2 RE-5111 NW 'A Section 9, T. 2 N., R. 65 W. Dear Mr. Kimmi: As you requested, I have prepared the attached calculations in support of the 100,000 cubic foot water quality pond shown on our drawings. The property slopes north at approximately one percent to a sump at the southeast corner of CR 41 at CR 24. Runoff from the property ponds there and is absorbed into the ground. I have attached a copy of • the stormwater management plan for the project, detailing additional background information. We propose a water quality pond along the north property line of this parcel. The temporary volume requirement is 100,000 cubic feet, and the permanent requirement is 13,000 feet. We propose that the pond be built to the larger size and left in place as a permanent feature. No building will be permitted in this area, and it will be revegetated with native grass. Sincerely, REAMS & PA ERSON, INC. Step-( Reams, PE*PL' Pre i,:: ,{ 13239 i;*i estooeir . goo se cie • _ 0_ a � € W 0 2 ac m lUll ca ci m = WOO^ =- t4a o a — . : , lam ��o i I _ %itfF - €Y$ 4 •4 4sn -1 r-- _ --- ,_ -t�_ - - a`i` { JdI '2 - • _ _aaS _ _i_— -_- _ agaag ---._/-2____i \,j I d --- ) I'— I 1 II I II I I I II w I' v 2 0 Ii I+ I \ I I F —1I __1C _._ --_ —1 rl- I iI 11 I I If 0 • • TABLE 1 Recommended Runoff Coefficients Source: Based on Tables RO-3 and RO-5 for Types C and D soils, USDCM Land use or Percent 2-year 5-year 10-year 100-year surface characteristics impervious BUSINESS Commercial areas 95 0.87 0.87 0.88 0.89 Neighborhood areas 85 0.60 0.65 0.70 0.80 RESIDENTIAL Single family * 0.40 0.45 0.50 0.60 Multi-family(detached) 60 0.45 0.50 0.60 0.70 Multi-family(attached) 75 0.60 0.65 0.70 0.80 Half-acre lot or larger * 0.30 0.35 0.40 0.60 Apartments 80 0.65 0.70 0.70 0.80 INDUSTRIAL Light areas 80 0.71 0.72 0.76 0.82 Heavy areas 90 0.80 0.80 0.85 0.90 PARKS,CEMETERIES 5 0.10 0.10 0.35 0.60 PLAYGROUNDS 10 0.15 0.25 0.35 0.65 SCHOOLS 50 0.45 0.50 0.60 0.70 RAILROAD YARDS 15 0.40 0.45 0.50 0.60 UNDEVELOPED AREAS • Historic flow analysis 2 (See lawns) Greenbelts, agricultural 2 (See lawns) Offsite flow analysis 45 0.43 0.47 0.55 0.65 (land use undefined) STREETS Paved 100 0.87 0.88 0.90 0.93 Gravel 40 0.15 0.25 0.35 0.65 CONCRETE DRIVES&WALKS 96 0.87 0.87 0.88 0.89 ROOFS 90 0.80 0.85 0.90 0.90 LAWNS,SANDY(A&B)SOIL 2%slope 2 0.05 0.06 0.08 0.10 2-7%slope 0.10 0.11 0.13 0.15 >7%slope 0.15 0.16 0.18 0.20 LAWNS,CLAY(C&D)SOIL 2%slope 5 0.13 0.14 0.15 0.17 2-7%slope 0.18 0.19 0.20 0.22 >7%slope 0.25 0.27 0.30 0.35 *See USDCM, Figures RO-3 through RO-5, for percent impervious • • • • N O CO O in NN Ymi J Q NCOC ° O O ,`V x O r O) Co 0 . 0 N r- CO S N Y p 1• 6 co CU CI d TrnCO 00 C O >,.0U 6000 o w 0 o • 0 a N N- N r CO N- y J < N (MO M N- 0) 6 T-0 X O O) N M L6 0' O U N cO N- O N -' p. r C 0 0 LO CO CU N O) O) Cr) O O 5 0 6 6 6 6 o o O a 0) 0) 0 c0 N V CO O co r M L O J Q O O (0 r c O 6 C• ?` O X '- m Lnrr N in O.U N .r) E C LO ca LO (.0 0 0 CO N O U d .) U 6600 a O In CY O C N 7 • r W (O L!) CO CO CO OD COQ C m zQ rnc000r 6 D X N- r r r F 0 �' O U c0 co M O CO N 6 re ✓ C O N- CO LO O N N 0 0 r 0 O 0 0 0 6 0 0 0 a ; E E w O O u O 0 V 0 r u LO L,- N (O N Cu Von-NO C 0) ti N r O O N 0 Q N N- O co o ° U N N CO.. r r m 0 U m p N O o) a c m E m o `m `o 0 a-o co d 0 L To .O m co j m a E o m n c o 6 to c mL m O. c a O) a Y R C m th - a a co a) a • to C Q N 0 c N ` O > U C N 4 LK0_ d' JH Cu • Water Quality Capture Volume Source: Figure SQ-2, USDCM 0.50 0.45 40-hour Drain Tim 0.40 24-hour Drain Tim p 0.35 2 0.30 l4VCV=at091;3-1.1912+0.781) 8 6-tr drain time a=0.7 e 0.25 12-hr drain time a =0.8 w 244r drain time a =0.9 40-hr drain time a = 1_0 0.20 • 3 0.15 — 0.08 inches 12-hour Drain Time H 0.10 6-hour Drain Time 0.05 0.00 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Total Imperviousness Ratio(I=I,,,/100) FIGURE SQ-2 Water Quality Capture Volume (WQCV), 80"' Percentile Runoff Event • • TABLE 3 Pond Volume Requirement For pond tributary area: Area Percent Impervious (sf) impervious area(sf) Rooftop 22,458 90% 20,212 Drives, parking, walks 77,374 100% 77,374 Semipermeable parking 206,721 40% 82,688 Landscaped area 1,296,268 2% 25,925 Total 1,602,821 206,200 Site imperviousness, I (percent) = 12.9 Water quality volume: Required water-quality storage(40-hour dry pond): 0.08 in Vwq =d *A = 11,031 ft3 Add 20%for sediment storage 2,206 ft3 Total Vwq 13,237 ft3 • Construction-period temporary sedimentation volume: Site area: 36.80 acres Required rate: 2,700 ft3/acre Volume required: 99,348 ft3 • N � L1 Steve Sharp Transportation ' County Road 41 at County Road 24 Hudson, Colorado ' Prepared for Steve Sharp Transportation ' • Cokeville, Wyoming I 1 1 1 Reams& • Patterson, Inc. Consulting Engineers and Land Surveyors 1 I. Storm Water Management Plan Steve Sharp Transportation County Road 41 at County Road 24 Hudson, Colorado 1 Prepared for: ' Steve Sharp Transportation c/o Bob Harrison 3500 East 156th Avenue Brighton, CO 80602 I• Prepared by: ' Stephen B. Reams, PE, PLS Reams & Patterson, Inc. 2950 South Jamaica Court, Suite 311 Aurora, Colorado 80014 (303) 745-4747 October 18, 2011 Project 11605 col . •o •T W Pla 323 5; IS II::' • Q St` •9i tomEE s••PO , 1 Steve Sharp Transportation Stormwater Management Plan Standard Notes ' The Permittee shall observe the following requirements. 1. The Permittee is required to obtain a CDPHE-WQCD Stormwater ' Discharges Associated with Construction Activity Permit before beginning work, and present it for inspection on request. The Permittee shall designate a Stormwater Management Plan (SWMP) Manager. The SWMP Manager will act as the project ' representative for any concerns or issues regarding environmental controls and stormwater management. ' 2. These requirements shall be the obligation of the Permittee, until such time as the Permit is properly closed, or otherwise voided, modified, transferred, re-assigned or replaced. ' 3. This SWMP narrative, the SWMP drawings, and inspection and maintenance records are all components of required record keeping and shall be kept on site at all times and updated as ' required. These and any other pertinent records shall be provided when requested. 4. Any discrepancy between this plan and any other approved I • Stormwater Management Plan for this site shall require compliance with the more restrictive plan. ' 5. Streets shall be constructed with Rough Cut Street Control measures, surface roughened or otherwise temporarily stabilized with rough cut street controls within seven days of completion of grading. If paving is to occur within 14 days after final grading, rough cut street controls shall be waived. 6. Inspection and maintenance of environmental, erosion and ' sediment control measures are the continuous obligations of the Contractor. Best Management Practices (BMPs) shall be inspected weekly and within 24-hours after the end of a precipitation event that produces run-off. All necessary maintenance and repairs shall be initiated and completed on an on-going basis, as features are required to operate continuously. Inspections may need to be conducted at a greater frequency than noted above, to ensure ' features and systems are operating adequately. Environmental, erosion and sediment control BMPs shall be maintained and functional for the entire duration of the project. 7. Ingress and egress vehicle access points onto disturbed areas shall be stabilized with Vehicle Tracking Control Pads (VTC) shall be constructed with angular rock, 6" minus, to a depth of at least ' 9- inches. The use of recycled asphalt or concrete is not permitted. The VTC shall be installed over a liner of non-woven • geotextile with a weight of at least 10 oz/yd2 and a grab tensile ' strength of at least 250 pounds. No dirt or other materials shall be placed on paved surfaces or curb flow lines to act as curb t ' Steve Sharp Transportation Stormwater Management Plan '• ramps. Only metal ramps or rock wattles may be used in the curb flow line. ' 8. Fugitive dust emissions resulting from grading activities and/or wind shall be controlled using reasonably available control ' technology as defined by the Colorado Department of Public Health and Environment. 9. All potential pollution sources on-site shall be identified and ' control measures installed and practiced to minimize the likelihood of a release. A Spill Prevention and Control Plan shall be developed for the site with measures in place to respond to any ' spills, leaks or other releases. 10. For all porous landscape detention facilities, in order to prevent clogging of filter medium, installation of the filtration system must be delayed until after the site is fully landscaped. 11. If stockpiles are located within 100 feet of a drainage way or a ' public storm sewer system, additional sediment controls such as temporary diversion dikes, silt fence, or sediment basin shall be required. • 1 1 • ii I Steve Sharp Transportation Stormwater Management Plan I• Table of Contents I I. SITE DESCRIPTION 1 A. DESCRIPTION OF CONSTRUCTION ACTIVITY 1 Description of activity 1 Site location 1 I Schedule and sequence 3 Areas and quantities 3 Topography and drainage 3 I Soils 4 Existing vegetation 5 Potential pollution sources 5 Non-stormwater discharges 5 I Receiving waters 5 II. STORMWATER POLLUTION PREVENTION 6 A. STORM WATER MANAGEMENT PLAN ADMINISTRATOR 7 I B. EROSION AND SEDIMENT CONTROLS 7 Structural practices 7 Non-structural practices 8 Scheduling summary 9 I C. MATERIALS HANDLING AND SPILL CONTROL 9 Fuel and oil 9 Concrete 10 I• Hazardous material 10 Dry material 10 Spill response 10 I Cleanup 10 Small spills 10 Larger spills 11 Notification 13 I Spills into or threatening state waters 13 Reportable quantity spill on land surface 13 Substances requiring notification 14 I Emergency Notification contacts 14 Reports 15 III. FINAL STABILIZATION AND LONG TERM MANAGEMENT 16 Stabilization 16 I Permanent maintenance 16 IV. OTHER CONTROLS 16 Waste disposal 16 I Sanitation 16 V. INSPECTIONS AND MAINTENANCE 17 Inspections 17 Silt fence 17 I Inlet protection 17 Curb socks 17 Revegetation 17 I Dust suppression 17 Street tracking 17 •• Perimeter check 17 VI. REFERENCES 18 I iv I •W I. Site description I ' A. Description of construction activity: Description of Steve Sharp Transportation proposes to construct an office and ' construction truck maintenance facility on a 34.56-acre site, generally located activity: at the southeast corner of County Road 41 and County Road 24 in unincorporated Weld County, Colorado. The project will include: • Construction of a 15,456 square foot building with an attached 7,000 square foot covered parking apron ' • 73,534 square feet of concrete surfaces and asphalt pavement • 206,721 square feet of semi-permeable asphalt parking area • Construction of a 100,000 cubic foot sedimentation basin at the northerly boundary of the property. The disturbed area will be approximately 15 acres. • Site location: Steve Sharp Transportation will be located on County Road 41 ' approximately one quarter mile south of County Road 24, in the northwest quarter of Section 9, Township 5 South, Range 65 West of the Sixth Principal Meridian and is shown on the Milton ' Reservoir Quadrangle USGS 7.5 minute topographic map. The geographic coordinates are 40°09'25" North, 104°40'25" West. The property is Lot A of Recorded Exemption No. 1307-09-2 RE-5111. 1• ' Steve Sharp Transportation Stormwater Management Plan • A vicinity map, from the Milton Reservoir Quadrangle, appears below. 1 _ M _ _ 4857 48ClI 4475 \ �' v I - moo j I �` k 1` JM1f i V ! A I I , 44.3 D.. 4 4G97 4045{{ :.8;,i„ \ D1 u3 %14o til v,' IP 8.50 ' aess 1 i WELDC0UNTYRO&Q4 •� 4952 _ 40 1981:. J ,. ei 4 ACCESS �,,; Disturbed Area 0" 6 ♦98g x885 ' 9 4@61 r W 114353O V JN \ 1 4 kle I WELD COUNTYR,AD21 ` . 69,5 U ears aass'�. ,r443 r8 E4&6] 4-8640 qc.6LE: •4 :, -le>40 •• l' s>o Figure 1 I Vicinity map, taken from Milton Reservoir Quadrangle 7.5 minute USGS map. Scale: one inch equals 2,000 feet. I 1•• 2 Pier Point Sewer Rehabilitation Project Stormwater Management Plan • Schedule and Construction will begin as soon as the required permits are in • sequence: hand, with the intent that grading will be complete and the concrete foundation is poured before winter weather sets in. Major project elements include, in sequential order: • Place initial erosion control measures and secure all required inspections. • Strip and stockpile vegetation and topsoil from area to be graded. Complete cuts and fills to subgrade. • Install road culvert, then place pavement on west portion of entrance drive. Remove temporary access road to south. ' • Form and pour building foundation. Place recycled asphalt pavement on parking area of site. 1 • Erect steel and construct building shell. Pour concrete floor for building and apron. • Drill well, install septic tank and drain field. Install ' electric, gas, and telephone service lines. • Construct concrete work and asphalt pavement surrounding building. ' • Seed and mulch all disturbed areas. Upon approval of erosion inspector, remove silt fence. • Complete interior construction for building. • Areas and quantities: Total area of the site boundary is approximately 34.56 acres. The area disturbed by excavation, pipelaying, and construction of a water quality pond is approximately 15 acres. Most of the 34.56-acre site will be undisturbed by construction. Topography and The site lies along a broad swale, roughly centered on County drainage: Road 24, draining easterly to Beebe Draw (channelized here and ' called Beebe Seep Canal), one and a half miles east. Average slopes in the area are 0.5 to 1 percent, with many local depressions that effectively prevent transmission of surface runoff during all but the most unusual rainfalls. Slopes range from 1 percent to 2 percent on the portion of the property that will be disturbed. The property drains to a large sump, two to three feet deep, at the southeast corner of County Road 41 and County Road 24. Vegetation and soil coloration suggests that the sump is large enough to contain most storms, and that overtopping, when it occurs, is across the road to a ' similar sump on the north side. There are no floodways, floodplains, nor wetlands on the site. The ' property lies within FEMA Community Panel 0802660900C, Zone C, areas of minimal flooding. f• I 3 I Steve Sharp Transportation Stormwater Management Plan ' • soils: A detail from the Weld County Soil Survey (Reference 3) appears in the Appendix; soils are described as generally sand and loamy ' sand. The survey describes some properties of the soils as follows: Erodability Soil Unified AASHTO Hydrologic Permeability ' Class Class Group K T Wind Erodibility Group Valent SP-SM or SM A-2,A-3 A 0.10 5 1 6.0-20 sand,3 to ' 9 percent slopes (Key 70) I Vona SM A-2,A-4 B 0.10 5 2 6.0—20(0-6 in deep) loamy 2.0-6.0(6-20 in deep) sand,e to 3 percent 6.0—20(28-60 in deep) I slopes (Key 72) I 1 . 4 i,r, 4. r a f 0 ' e R 'i ! x c 4+ ' a .4, ' likI w. t =. `.k, r is 9 it1111 k • . It x x+'ga f%r ps a+° } tic4 A 10 } Rye $.LJ >4�k. a—.•.. ..... 4.s.. ..++'.. v , .. W 4 E I , , J i I y�Y.� Figure 2 • Detail from Map 23, USDA `Soil Survey of Weld County, Colorado, Southern Part," 1980. Scale: one inch equals 2,000 feet. I 4 Pier Point Sewer Rehabilitation Project Stormwater Management Plan '• Existing The property is covered with low vegetation of moderate density, vegetation: with several track roads traversing the area. Effective ground cover is approximately 60 percent. Potential pollution The contractor will be required to provide and maintain adequate ' sources: temporary sanitary facilities and maintain them on a timely basis. Any spills will be corrected immediately. ' The work will generate a significant quantity of waste concrete and excess construction materials. Waste materials must be removed from the property and taken to an approved disposal site. Collect construction debris and trash in appropriate containers daily, and see that the containers are emptied as needed. ' Fueling and lubrication of construction equipment will require precautions as described below. These operations will be conducted from appropriately equipped service vehicles, and there will be no on-site storage of fuels, oils, or lubricants. Maintenance of equipment and vehicles will be limited to emergencies, and will require the precautions described below. Very little hazardous material will be required for the work. Concrete will be delivered in ready-mix trucks. Sealants, disinfectants, and other potentially hazardous materials will be • properly labeled and stored as described below.INon-stormwater It is not expected that the Contractor will encounter ground water discharges: during construction. Dewatering, if needed, will require a ' dewatering permit from the Colorado Department of Public Health and Environment. Adequate measures must be provided to properly clean the discharge from dewatering, and to return the water in accordance with CDPHE requirements. Receiving waters: The site lies along a broad swale, roughly centered on County Road 24, draining easterly to Beebe Draw (channelized here and called Beebe Seep Canal), one and a half miles east. Average slopes in the area are 0.5 to 1 percent, with many local depressions that effectively prevent transmission of surface runoff ' during all but the most unusual rainfalls. Any site runoff actually reaching Beebe Seep Canal will be carried north and would ultimately reach the South Platte River. I I I • 1 Steve Sharp Transportation Stormwater Management Plan 1e II. Stormwater pollution prevention 1 It is the Owner's intent and direction that all construction operations be conducted with all due precautions to protect adjacent properties from damage by erosion and sedimentation. When, despite those precautions, damage may occur, it is imperative that the Contractor act immediately and effectively to mitigate and remedy the damage. The erosion control plan represents the Engineer's estimation of how, in general, construction will proceed. The Engineer cannot ' anticipate all the methods, sequencing, and procedures to be used, because they are quite properly within the Contractor's domain. Neither can the Engineer supply a plan in sufficient 1 detail to meet all the day-to-day exigencies of the construction process. The plan is intended as general guidance only, and must be supplemented by such measures as may be needed to meet the overall objectives of protecting the adjacent properties and downstream waters. The Contractor must plan the construction operations with due regard for the external effects of those operations. Continuously review the drainage patterns as they will exist, and be sure that the erosion control measures shown on the plan will be adequate I • to protect adjacent property and waters. Maintain a daily watch on weather forecasts, and take precautions as needed to prepare for precipitation and high winds. Be mindful that weather in this vicinity often develops quickly, and may be violent. Before leaving 1 the site each day, insure that precautions have been taken to protect against a sudden storm. If it appears that the planned erosion control measures are not performing adequately, consult with the Owner and Engineer promptly. The Contractor shall make regular inspections of all erosion control measures, check the effects of the construction work on adjoining properties and downstream waters, make any required repairs so that all Best Management Practices (BMPs) are continuously functional, and maintain all records as required by the State of Colorado. Detailed maintenance requirements are included in this report. 1 1 1 1• 1 6 Pier Point Sewer Rehabilitation Project Stormwater Management Plan • A. Storm Water Management Plan Administrator: 1 The SWMP Administrator is a specific individual(s), position or title who is responsible for developing, implementing, maintaining, and revising the SWMP. The activities and 1 responsibilities of the administrator shall address all aspects of the facility's SWMP. The SWMP Administrator for this project is: Name, Position, or Title Date Appointed For revisions: Name, Position, or Title Date Appointed Name, Position, or Title Date Appointed I Name, Position, or Title Date Appointed I. ' Name, Position, or Title Date Appointed B. Erosion and sediment controls: Review the planned construction events on a regular basis, and adjust as necessary to maintain continuous protection against ' illicit discharges. Update this report and the Stormwater Management Plan to reflect all field changes. Structural practices: Before beginning construction on any phase of the work, place (or rehabilitate if needed) every erosion control required by this plan. Measures will include: 1 • Silt fence (SF) along the downhill limits of all disturbed areas. 1 • Place Vehicle Tracking Control (VTC) at the end of the access road, adjoining the paved surface of County Road • 41. When the paved permanent entrance drive is complete, the 300-foot paved length will serve as the VTC, and the temporary one may be removed. Clean the asphalt surface 1 7 Steve Sharp Transportation Stormwater Management Plan ' • as often as necessary to prevent dirt and mud from being tracked onto County Road 41. ' • Install concrete washout area (CWA) along the entrance drive near County Road 41. When the permanent entrance road has been completed, relocate the CWA to a 1 convenient point along the drive, near the entrance to County Road 41. Maintain 50 feet of clearance between the CWA and the roadside ditch. • Use water truck, surface roughening, or other measures as needed to prevent blowing dust. Non-structural In conjunction with the structural measures listed above and practices: shown on the plans, good construction practice and local 1 conditions require additional non-structural measures. These will include: • Where circumstances allow, locate spoil bank on high side of trenches. • Sweep (not wash) County Road 41 and paved project drives weekly (more often as required) and remove dirt. • Disc, seed, mulch, and crimp disturbed areas as soon as I• work is complete and weather permits. • Complete final restoration of pavement, curbs, pans, walks, and landscaping as soon as conditions permit, and 1 take any required remedial measures to yield clean, true pavements, curbs, pans, hardscapes, and walks and vigorous, healthy permanent landscaping equal to or better than original existing conditions. I 1 I r• 1 8 1 Pier Point Sewer Rehabilitation Project Stormwater Management Plan • Timing of BMP placement and removal will be as follows:•O Scheduling Summary Control Measure Scheduled Placement Scheduled Removal Remarks I Vehicle tracking control Before any construction When construction is in the affected phase substantially complete and no further vehicle access I required. Concrete washout Before any concrete When concrete delivery is delivery complete and no further concrete required ' Seed and mulch As soon as Water as needed to underground work and establish permanent grading are complete, vegetation in all affected and weather permits. areas. I Final landscaping,pavement,and As soon as prudent Permanent walks construction practice permits,after access is no longer needed over Iaffected area. IC. Materials handling and spill control: • Review this plan periodically to ensure that it makes adequate provision for the materials and processes actually present on the project site. Read and post materials safety data sheets for all I materials present or planned for use. Implement this plan in conformance with the current requirements of all agencies having jurisdiction. I Fuel and oil: Do not store fuel, oil, hydraulic fluids, and grease for vehicles and equipment on site. Use spill pans beneath equipment fueling operations. Monitor fueling hoses continuously when in use. I Immediately clean up any spillage and dispose of it in an approved manner. Oil and oily wastes such as crankcase oil, cans, rags, and paper dropped into oils and lubricants must be I disposed of in proper receptacles or recycled. Used oil for recycling shall not be mixed with degreasers, solvents, antifreeze, or brake fluid. Perform all fueling and lubrication from vehicle- mounted fuel and oil service trucks, and immediately clean up I any spills. Do not park fuel and oil service trucks on site outside of work hours. Maintain an adequate stock of absorbents on each fuel and oil service truck. IPerform vehicle and machine maintenance off site whenever possible. If emergencies require on-site repair, use adequate and effective measures to prevent spills. Place impervious liner Ibeneath work area, turning up the edges to form a sufficient • containment for any potential spill. Maintain an adequate and readily available stock of absorbents, and use to clean up any '• spills. I 9 Steve Sharp Transportation Stormwater Management Plan • Concrete: Provide portable, temporary concrete washout facilities whenever concrete work is performed. Place secondary spill containment ' beneath portable washout facilities. Details are given in the structural BMP section. Capture and clean up water and residue from concrete and asphalt sawing. ' Hazardous material: Store solvents, paints, chemicals, fertilizers, and other hazardous substances in enclosed containers located away from watercourses, inlets, storm drains, and other vulnerable locations. Clearly label all products, keep tanks off the ground; and keep lids securely fastened. Create an impervious berm around the perimeter of tanks and drums with a capacity of 110 percent of the capacity of the largest container. Dry material: Use the recycled asphalt parking area or available hard surface ' areas for staging and storage of construction materials. This offers the advantage of greatly reducing the percentage of delivery vehicles that will have an opportunity to track mud onto the ' streets, while affording a clean surface for the storage of the material. Spill response: Review this plan periodically to ensure that it makes adequate ' provision for the materials and processes actually present on the project site. Read and post materials safety data sheets for all materials present or planned for use. I • NOTE: IN CASE OF FIRE, EVACUATE EVERYONE FROM ' THE IMMEDIATE AREA, RENDER FIRST AID TO ANYONE WHO IS INJURED, AND DIAL 911 IMMEDIATELY. TAKE APPROPRIATE STEPS TO PROTECT HUMAN LIFE AND TO CONTROL FIRES FIRST. SPILL CONTROL IS A SECONDARY CONCERN. 1 Cleanup: First, ensure personal safety. Turn off or removed all possible ignition sources, including running engines, electrical equipment (including cellular telephones, etc.), or other hazards. Evaluate the extent of the spill and the nature of the spilled material to determine if remedial actions could result in any health hazards, escalation of the spill, or further damage that would intensify the ' problem. If such conditions exist, notify the construction supervisor immediately, cordon off the area of the spill, and protect the area until adequate help arrives. If it can be done safely, identify the source of the spill and if possible stop the flow of pollutants. However, no one will attend to the source or begin cleanup of the spill until ALL emergency priorities (fire, injuries, etc.) have been met. • Small spills: Small spills (usually less than 5 gallons) consist of minor quantities of gasoline, oil, anti-freeze, or other materials that can 10 ' Pier Point Sewer Rehabilitation Project Stormwater Management Plan 1• be cleaned up by a single person using readily available materials. Use the following procedures for clean up of small spills: ' 1. Ensure personal safety, evaluate the spill, and if possible, stop the flow of pollutants. 2. Contain the spread of the spill using absorbents, portable berms, sandbags, or other available measures. 3. Spread absorbent materials on the area to soak up as much of the liquid as possible and to prevent or minimize infiltration into the soil. ' 4. Once the liquids have been absorbed, remove all absorbents from the spill and place the materials in a ' suitable storage container. On paved areas, wipe any remaining liquids from the surface and place the materials in a storage container. Do not spray or wash down the ' area using water. For open soil areas, excavate any contaminated soil as soon as possible and place the soil in a suitable storage container. All materials will then be transported off-site for disposal. ' 5. If immediate transfer and storage of the contaminated soil is not practical, excavate and place the contaminated soil I• on a double thickness sheet of 3-mil or heavier polyethylene film. In addition, form a small berm around the outer edges of the soil stockpile, underneath the polyethylene film, to ensure that contaminants are not washed from the site if it rains or snows and that materials do not seep through the berm. ' 6. Record all significant facts and information about the spill, including the following: • Type of pollutant ' • Location • Apparent source • Estimated volume I • Time of discovery • Actions taken to clean up spill 7. Notify the supervisor of the spill and provide the information from Item 6. The supervisor will then contact the appropriate agencies. Larger spills: Medium to large spills consist of larger quantities of materials (usually 5 to 25 gallons) that are used on site that cannot be controlled by a single employee. Generally, a number of people will be needed to control the spill and a response may require the suspension of other activities. Use the following procedures for • clean up of small spills:•' II ' Steve Sharp Transportation Stormwater Management Plan • 1. Ensure personal safety, evaluate the spill, and if possible, stop the flow of pollutants. 2. Immediately dispatch a front-end loader or similar equipment to the spill and construct a berm or berms ' downhill from the spill to minimize the spread of potential pollutants. On paved surfaces, use portable berms, sandbags, booms, or other measures to control the lateral spread of the pollutants. 3. When the spread of the spill has been laterally contained, contact the supervisor or designated individual and ' provide them information on the location, type, and amount of spilled material, and a briefing on the extent of the spread and measures undertaken to contain the ' contaminants. 4. Depending on the nature of the spill, mobilize additional ' resources as needed to contain the contaminants. 5. Begin cleanup when the lateral spread has been contained and the notification to the supervisor has been made. ' 6. Bail or pump freestanding liquid into 55-gallon storage drums, steel tanks, or other suitable storage containers. • When all the liquid has been removed from the pavement I or soil layer, apply absorbents to the surface and transfer them to the storage containers when they have soaked up as much of the spill as possible. 7. On paved surfaces, remove the remaining contaminants, to the extent possible, with rags, sweeping, or similar ' measures. DO NOT spray or wash down the area of the spill using water. Place any contaminant-soaked materials into the storage containers with the other absorbents. 1 8. Excavate the remaining contaminated soils and load into truck(s) for disposal off-site at a designated facility. If transport off-site is not immediately available, stockpile ' the remaining soils on a double thickness sheet of 3-mil or heavier polyethylene film. In addition, form a small berm around the outer edges of the soil stockpile, underneath ' the polyethylene film, to ensure that contaminants are not washed from the site by rain or snow and do not seep through the berm. ' 9. Record all significant facts and information about the spill, including the following: ' • Type of pollutant • Location • • Apparent source • Estimated volume 1 12 Pier Point Sewer Rehabilitation Project Stormwater Management Plan • • Time of discovery • Actions taken to clean up spill 10. Notify the supervisor of the spill and provide the information from Item 9. The supervisor will then contact ' the appropriate agencies. Notification: Notification to the Colorado Department of Public Health & Environment (CDPHE) is required if there is any release or suspected release of any substance, including oil or other substances that spill into or threaten State waters. Unless otherwise noted, notifications are to be made by the supervisor and only after emergency responses related to the release have been implemented. This will prevent misinformation and assures that notifications are properly conducted. ' The notification requirements are as follows: 1. Spills Into or Threatens State Waters: Immediate ' notification is required for releases that occur beneath the surface of the land or impact or threaten waters of the State of threaten the public health and welfare. INotifications that will be made are: a. For any substance, regardless of quantity, contact • CDPHE at 1-877-518-5608. State as follows:I i. Give your name. ii. Give location of spill (name of city). I iii. Describe the nature of the spill, type of products, and estimate size of spill. iv. Describe type of action taken thus far, type of assistance or equipment needed. b. For any quantity of oil or other fluids, call the ' National Response Center at 1-800-424-8802. State as follows: i. Give your name. ii. Give location of spill (name of city). iii. Describe the nature of the spill, type of products, and estimate size of spill. ' iv. Describe type of action taken thus far, type of assistance or equipment needed. 2. Reportable Quantity Spill on Land Surface: Immediate 1 notification is required of a release upon the land surface of an oil in quantity that exceeds 25 gallons, or of a hazardous substance that equals or exceeds 10 pounds or its reportable quantity under Section 101(14) of the Comprehensive Environmental Response, Compensation • Liability Act (CERCLA) of 1980 as amended (40 CFR Part 302) and Section 329 (3) of the Emergency Planning and 1 13 I Steve Sharp Transportation Stormwater Management Plan '• Community Right to Know Act of 1986 (40 CFR Part 355) whichever is less. This requirement does apply at a ' minimum to the substances listed in Table A below. TABLE A I Substances Requiring Notification Substance Reportable Quantity Motor oil 25 gallons I Hydraulic oil 25 gallons Gasoline or diesel fuel 25 gallons IThe notification procedures to be followed are: a. Give your name. I b. Give location of spill (name of city and state). c. Describe nature of the spill, type of product, and estimate size of spill. d. Describe type of action taken thus far, type of I assistance or equipment needed. e. Give name of land owner. f. Specify department responsible for any facilities Ithat may be impacted 3. Notification is not required for release of oil upon the land I• surface of 25 gallons or less that will not constitute a threat to public health and welfare, the environment or a threat of entering the waters of the State. I 4. Notification, as required in paragraphs 1 and 2 above, will be made to the CDPHE using the 24-hour telephone number to report environmental spills. All information I known about the release at the time of discovery is to be included, such as the time of occurrence, quantity and type of material, location and any corrective or clean-up actions presently being taken. Table B lists these phone I numbers. TABLE B I Emergency Notification Contacts Name of Agency Number I Hudson Fire Protection District 911 Weld County Sheriff's Office 911 Ambulance 911 Hospital 911 I National Response Center 1-800-424-8802 CDPHE— Report Environmental Spills 1-877-518-5608 (24 hours a day) IColorado Emergency Planning Committee.. 303-273-1622 • 5. It is the responsibility of the supervisor to contact Weld ' County, CDPHE, and the National Response Center. 14 Pier Point Sewer Rehabilitation Project Stormwater Management Plan • a. The National Response Center is to be contacted when a release containing a hazardous substance ' or oil in an amount equal to or in excess of a reportable quantity established under either 40 CFR 110, 40 CFR 117, or 40 CFR 302 occurs ' during a 24-hour period. b. Notification to the CDPHE is required if there is 1 any release or suspected release of any material, including oil or hazardous substances that spill into or threaten state waters. ' Reports: The CDPHE requires written notification of a spill or discharge of oil or other substance that may cause pollution of the waters of the State of Colorado. A written report must be submitted to the ' Water Quality Control District (WQCD) within five days after becoming aware of the spill or discharge. The CDPHE requires a written final report within 15 days for all ' releases of an oil or hazardous substance that require implementation of a contingency plan. The CDPHE may also require additional reports on the status of the clean up until any ' required remedial action has been complete. Written notification of reports must contain at a minimum: I• 1. Date, time, and duration of the release. 2. Location of the release. 3. Person or persons causing and responsible for the release. 4. Type and amount of oil or substance released. 5. Cause of the release. 6. Environmental damage caused by the release. 7. Actions taken to respond, contain, and clean up the release. 8. Location and method of ultimate disposal of the oil or other fluids. 9. Actions taken to prevent a reoccurrence of the release. 10. Any known or anticipated acute or chronic health risks associated with the release. ' 11.When appropriate, advice regarding medical attention necessary for exposed individuals. I 1• ' 15 Steve Sharp Transportation Stormwater Management Plan se III. Final stabilization: Stabilization: All property disturbed by this project will be stabilized by finished improvements or seed and mulch. ' Maintenance: All improvements will be maintained by the landowner. Seeded areas must be watt=ered as needed to establish a satisfactory vegetative cover on all disturbed areas not covered by buildings, asphalt, concrete, or recycled asphalt semi-permeable pavement. There are no permanent water quality facilities associated with this project. IV. Other controls: ' Waste disposal: Waste materials must be removed from the property and taken to an approved disposal site. Broken concrete, asphalt pavement, and other such materials may not be buried, but must be taken ' to an approved disposal site. Collect construction debris and trash in appropriate containers daily, and see that the containers are emptied as needed. I• Sanitation: Provide an adequate number of portable toilets for the work force being employed. Locate them on level, dry ground, away from water courses, inlets, and ponds, and at least 100 feet from any residential building. Insure that the units are serviced weekly, and immediately clean up any spills. • 16 Pier Point Sewer Rehabilitation Project Stormwater Management Plan V. Inspections and maintenance: 1 Inspections: During construction and prior to initial closeout acceptance, the Contractor shall make regular inspections of all erosion control ' measures and check the effects of the construction work on adjoining properties and downstream waters. At a minimum, inspections are required at least every 7 days, and within 24 ' hours after every precipitation event (including snowmelt). The Contractor shall keep a written log of each inspection, including deficiencies noted and corrective action taken, and shall make all logs available upon request. ' Following initial closeout acceptance, and until permit closeout, self-inspect the site at least every 30 calendar days, and within 24 hours after the end of any every precipitation event (including snowmelt). ' Silt fence: Check silt fence for leaning posts and torn or damaged fabric, and repair as needed. Remove silt when it reaches a depth of 6 inches. Watch for bulging fabric and other signs of excess stress, and add posts as needed. Correct any piping beneath or around the fence. Close any gaps in the fence, including temporary openings for construction work. I • Revegetation: Check for general health of planting, to see that correct amount of irrigation is being applied. Reseed if first planting does not yield a good stand of vegetation. Check straw/coconut woven matting, if used, for proper anchorage and position. 1 Dust suppression: Use water truck and other measures as needed to prevent blowing dust. Street tracking: Require everyone to exit via the vehicle tracking control, and close off any alternative routes as they develop. Renew rock as needed to keep the tracking pad clean and effective. Monitor use of the pad by traffic, and widen or lengthen it as needed. Promptly clean up any material tracked onto adjoining streets and driveways by shoveling and sweeping, not by flushing with water. Perimeter check: Walk the perimeter of the site daily to detect any adverse erosion or deposition on neighboring properties, and promptly repair any ' damage. Take such steps as may be necessary to prevent recurrence. 1 • ' 17 ' Steve Sharp Transportation Storm water Management Plan ' Ask VI. References: ' 1. United States Department of Agriculture, Soil Conservation Service, Soil Survey of Weld County, Colorado, Southern Part, 1980. ' 2. Wright-McLaughlin Engineers, Urban Storm Drainage Criteria Manual (three volumes), Urban Drainage and Flood Control District, 2002. 3. U.S. Department of Homeland Security, Federal Emergency Management Agency, "Flood Insurance Rate Map, Weld County, Colorado Unincorporated Areas," Community Panel No. 080266 0900 C," revised September 28, 1982. 1 • 1 • 1S Hello