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Home My WebLink About20130396.tiffRECEIVED WASTE MANAGEMENT APP 1 s In17 Weld County Planning Department GREEL_FY OFFICE April 8, 2013 Mr. Matt Burgett Colorado Department of Public Health and Environment Air Pollution Control Division APCD-SS-Bl 4300 Cherry Creek Drive South Denver, CO 80246-1530 RE: Buffalo Ridge Landfill Title V Operating Permit Number 03OPWE260 Semi -Annual Monitoring Report Dear Mr. Burgett: DEEa1VEE8 ARAPAHOE ®ESPOSAL SITE aDAE&S) PO Box 460397 3500 South Gun Club Road Aurora, CO 80046-0397 (720) 876-2620 (303) 690-8138 Fax In accordance with Title V Operating Permit #03OPWE260, attached is the Semi-annual Monitoring and Deviation Report for October 1, 2012 through March 31, 2013 for the Buffalo Ridge Landfill. If you have any questions about this report, please contact me at (720) 876-2621. Sincerely, Doc Nyiro Environmental Engineer Attachment Mtry)uuvu Ca+ttNkS 61) X13 -03°1y cc: Bruce Clabaugh, WMC Christian Colline, Waste Management Eric DiEsposti, WMC Jack Epple, WMC Bill Hedberg, WMC Douglas Ikenberry, CDPHE Kim Ogle, WCDPS, w/o attachment Dana Podell, CDPHE, w/o attachment Tom Schweitzer, WMC Troy Swain, WCDPHE David Thorley, Waste Management Rodney Walter, Waste Management C\Users\dnyim\Doeuments\dnta\13uf alo Ride\Air Compliance\2013\Title V Semi -Annual Monitoring Report 1st 2013 Cover Latter Boca WASTE NMAEIACEMEBUT April 8, 2013 Mr. Charles Johnson Colorado Department of Public Health and Environment Hazardous Materials and Waste Management Division 4300 Cherry Creek Drive South Denver, CO 80246-1530 2400 West Union Avenue Englewood, CO 80110 303-914-1445 (Phone) 303-914-9937 (Fax) RECEWE APR 1 7013 Weld County Planning Department GREELEY OFFICE Subject: Buffalo Ridge Landfill (BRLF) Updated Closure/Post-Closure Plan and Financial Assurance Plan Dear Mr. Johnson: Enclosed are updated closure/post-closure and financial assurance plans which have been revised to reflect current operations at BRLF and anticipated closure and post -closure activities. Section 1.8.3 (C) of the Colorado Regulations Pertaining to Solid Waste Disposal Sites and Facilities, 6CCR-1007-2, requires an annual adjustment to the closure and post -closure financial assurance cost estimate by using the implicit price deflator (IPD) for the gross domestic product. The IPD for 2013 is 1.018 as confirmed with the Colorado Department of Public Health and Environment. The closure and post -closure cost estimates respectively contained in Appendix A and Appendix B of the enclosed financial assurance plan were adjusted using this value. The insurance certificate contained in Appendix C of the financial assurance plan reflects this adjustment to the referenced cost estimates. The insurance certificate and updated plans have been placed in the facility operating record. Please call me at (303) 914-1445 or Doc Nyiro at 720-876-2621 if you have questions about the enclosures. Sincerely, Tom Schweitzer, P.E. Senior Engineer Enclosures cc: Deborah Blandin, WCDPHE Kim Ogle, WCDPS Douglas Ikenberry, CDPHE Jack Epple/BRLF Operating Record Doc Nyiro, Waste Management of Colorado Bill Hedberg, Waste Management of Colorado Donna Meals, Waste Management, w/o enclosures C:\Users\tschweit\Documents\mydata\FinAssurance13\BRLF FinAssur Transmittal Ltr - 04-2013.docx FINANCIAL ASSURANCE PLAN BUFFALO RIDGE LANDFILL Weld County, Colorado Prepared by: Waste Management of Colorado, Inc. Buffalo Ridge Landfill 11655 Weld County Road 59 Keenesburg, Colorado 80643 Updated March 2013 FINANCIAL ASSURANCE PLAN BUFFALO RIDGE LANDFILL TABLE OF CONTENTS Section page 1.0 INTRODUCTION 1 2.0 REGULATORY REQUIREMENTS 1 2.1 COST ESTIMATES 1 2.2 FINANCIAL ASSURANCE ACTIVITIES 1 2.3 FINANCIAL ASSURANCE MECHANISMS 2 3.0 CLOSURE AND POST -CLOSURE COSTS 2 4.0 FINANCIAL ASSURANCE MECHANISM 2 LIST OF APPENDICES Appendix A Closure Costs B Post -Closure Care Costs C Insurance Certificate for Closure and Post -Closure Care Costs Financial Assurance Plan Updated March 2013 Buffalo Ridge Landfill FINANCIAL ASSURANCE PLAN BUFFALO RIDGE LANDFILL REVISION LOG DATE DESCRIPTION OF REVISION BY 04/02 General plan review and update. Replaced original cost estimates based on 2002 CDPHE guidance or as determined by BRL. Changed financial assurance mechanism from letter of credit to insurance certificate. TSS/ARS 03/03 Revise financial assurance costs based on the revised closure and post- closure plan dated March 2003 TSS/ARS 03/05 Revise financial assurance costs based on the revised closure and post- closure plan dated March 2005 TSS/ARS 3/06 Revised financial assurance costs in response to the Colorado Department of Public Health and Environment (CDPHE) letters dated January 11 and February 13, 2006. TSS/ARS 3/07 Replaced cost estimates of closure and post -closure prepared in 2002 with new cost estimates in accordance with Section 1.8.3 of the Solid Waste Regulations. Miscellaneous text changes were also made to the Plan. TSS/ARS 3/09 Updated to reflect changes to closure and post -closure plan updated March 2009. JW 8/09 Updated to reflect changes to closure and post -closure plan updated August 2009. JW 03/10 Updated to reflect changes to closure and post -closure plan updated March 2010. JW 03/11 Updated to reflect changes to closure and post -closure plan updated March 2011. JW 03/12 Replaced cost estimates of closure and post -closure prepared in 2007 with new cost estimates in accordance with Section 1.8.3 of the Solid Waste Regulations. Miscellaneous text changes were also made to the Plan. TSS 03/13 Updated •to reflect changes in maximum area requiring 3Ta party closure and amount of backfill required to meet 5% slopes. DN/TSS Financial Assurance Plan Buffalo Ridge Landfill Updated March 2013 1.0 INTRODUCTION This revised Financial Assurance Plan (Plan) has been prepared in accordance with Section 1.8 of the Regulations Pertaining to Solid Waste Disposal Sites and Facilities, 6 CCR 1007-2, (Regulations) and sets forth the closure and post -closure care costs for Buffalo Ridge Landfill (BRL) in Keenesburg, Colorado. This Plan includes in Appendices A and B closure and post - closure cost estimates, adjusted to 2013 dollars, which replace all previous estimates. The Regulations require that cost estimates be replaced every five (5) years or as otherwise required by the Colorado Department of Public Health and Environment (CDPHE) and cost estimates were last replaced in 2012. The next replacement of cost estimates is scheduled for 2017. This Plan also describes the financial assurance mechanism in place to ensure payment of all associated closure and post -closure costs. This Plan is to be used in conjunction with the BRLF Closure/Post Closure Plan dated March 2013. 2.0 REGULATORY REQUIREMENTS 2.1 COST ESTIMATES Section 1.8 of the Regulations lists the specific fmancial assurance requirements for solid waste disposal sites. These requirements are described below: 1. Maintain cost estimates, in current dollars, for hiring a third party to close the largest area of the facility requiring closure during the active life of the site. The cost estimate must also include costs associated with conducting post -closure care. 2. The facility must establish financial assurance sufficient to ensure payment of the third -party closure and post -closure care costs. 2.2 FINANCIAL ASSURANCE ACTIVITIES The following are the requirements for financial assurance activities as described in Section 1.8 of the Regulations: 1. Notify the CDPHE when the required cost estimates have been placed in the operating record; 2. Annually adjust cost estimates to account for inflation using the method prescribed by CDPHE; 3. Replace original cost estimates with new cost estimates every five (5) years, unless otherwise required by CDPHE; 4. Costs associated with closure, post -closure and corrective actions may be adjusted Financial Assurance Plan 1 Updated March 2013 Buffalo Ridge Landfill after approval by CDPHE and the local governing authority; 5. Financial assurance must be provided continuously unless a release is granted by CDPHE. 2.3 FINANCIAL ASSURANCE MECHANISMS Several financial assurance mechanisms are available, and more than one mechanism may be used. For corporate entities, these mechanisms include a trust fund, letter of credit, surety bond and insurance. Waste Management of Colorado, Inc. (WMC) has chosen to use insurance to meet the financial assurance requirements. The insurance certificate was prepared in accordance with the requirements set forth in Section 1.8.9 of the Regulations. 3.0 CLOSURE AND POST -CLOSURE COSTS Closure and post -closure costs are those costs associated with closing the facility and conducting post -closure care activities. These costs are determined by calculating the cost to complete all of the actions in the Closure/Post Closure Plan. The unit cost values for closure and post -closure activities were determined by WMC. Costs for items including earthwork, excavation and soil placement, were taken from recent bids for similar work completed at Waste Management construction projects. The closure costs are provided in Appendix A, and the post -closure costs are provided in Appendix B. 4.0 FINANCIAL ASSURANCE MECHANISM WMC has established insurance coverage to assure adequate funds are available for all closure and post closure care costs determined in the Closure/Post-Closure Plan. The insurance meets all requirements set forth in Section 1.8.9 of the Regulations, "Insurance for Closure and Post - Closure". The insurance certificate is provided in Appendix C. Financial Assurance Plan 2 Updated March 2013 Buffalo Ridge Landfill APPENDIX A CLOSURE COSTS TABLE 1 = CLOSURE COST ESTIMATE Site: BUFFALO RIDGE LANDFILL Date: March -13 • Item Description Units Quantity Unit Cost (Note 1) Extended Cost Category Cost 1 Foundation Layer a Backfill of intermediate grades to achieve minimum 5% slope (on -site source) CY 327,000 1.85 604,950 b Other Foundation Layer Closure Costs CY 1.85 0 Foundation Layer Total Cost 604,950 2 Final Cover Section Closure Area: 39.0 Acres a Compacted Clay Layer (on -site source) CY 0 b Alternative Final Cover (on -site source) CY 110,000 1.60 176,000 c Topsoil (on -site source) CY 32,000 2.35 75,200 d Fertilizer/Soil Amendements/material hauling Acre 39.0 1,215.00 47,385 e Seeding Acre 39.0 145.00 5,655 f Other Final Cover Closure -Related Costs Acre 0 Final Cover Total Cost 304,240 3 Surface Water Controls (Note 2) a Drainage Swales/Berms/Channels 0 b Culverts 0 c Sedimentation/Surface Wtr Control Ponds 0 d Erosion Control 0 e Other Surface Water Closure -Related Costs p Surface Water Total Cost 0 4 Environmental Monitoring Installations a Grndwtr Mntg Wells w/dedicated pumps EA 0 b Gas Monitoring Probes EA 0 c Pumping of temporary trench system tank EA 1 3,600.00 3,600 Environmental Monitoring Total Cost 3,600 5 Gas Collection and Control System (GCCS) a Extraction Well Installation 0 b Extraction Well - Well Head Assembly 0 c Extraction Well - Lateral Pipe 0 d GasNapor Collection - Header Pipe 0 e GasNapor Collection - Header Drain 0 f Blower 0 g Blower Enclosure/Building 0 h Flare 0 i Other GCCS Closure -Related Items 0 GCCS Total Cost 0 TABLE 1 - CLOSURE COST ESTIMATE (Continued) Site: BUFFALO RIDGE LANDFILL Date: March -13 • Item Description Units Quantity Unit Cost Note 1) Extended Cost Category Cost 6 7 8 9 Miscellaneous Closure Activities a Access Road Construction 0 b Fencing (asbestos disposal area) 1 48,800.00 48,800 c Signs EA 2 150.00 300 d Removal/backfill of temporary trench system tank EA 1 25,100.00 25,100 Miscellaneous Total Cost 74,200 CLOSURE COST ESTIMATE SUBTOTAL 986,990 Engineering & Project Management a Design & Bid Documents (% of Subtotal) 3% 29,610 b CQA, Surveys & Reports (% of Subtotal) 10% 98,699 c Project Mgmt & Admin (% of Subtotal) 2% 19,740 d Engineering & Project Mgmt Total Cost 148,049 Contingency (% of Subtotal) 10% 98,699 10 CLOSURE COST ESTIMATE TOTAL (in 2012 dollars) $1,233,738 11 Inflation adjustment factor for 2013 1.018 12 Inflation adjustment factor for 2014 13 Inflation adjustment factor for 2015 14 Inflation adjustment factor for 2016 Total Closure Cost (adjusted to 2013 dollars - Line 10 x Line 11) $1,255,945 otes: 1 All costs include material and installation unless noted otherwise. 2 Costs to enlarge existing surface water control structures to meet closure requirements. APPENDIX B POST -CLOSURE CARE COSTS TABLE 2 - POST -CLOSURE COST ESTIMATE Site: BUFFALO RIDGE LANDFILL Date: March -13 Acres at Closure: Item Description Units Unit Quantity Unit Cost Quantity per Year Cost per Year 1a Facility Inspections & Reporting - 2 per year EA 1 1,150 2 2,300 1 b Facility Inspections & Reporting - 2 addt'l events to allow for qtrly inspections first 2 yrs of post -closure. Annual cost for 2 addt'I events = 2,300 Total Item cost for 2-yr period = 4,600 Total Item cost annualized over 30 yr PC period = 153 2 Qualitative Vegetative Assessement - annual EA 1 3,432 1 3,432 3a Cover Maintenance, Reseeding & Fertilizing - 5% of site per year (Note 1) AC 5% 2,040 2.0 3,978 3b Cover Maintenance, Reseeding & Fertilizing - addt'l 5% per year to allow for 10% of the site first 2 yrs of post -closure Annual cost for addt'I 5% = 3,978 Total Item cost for 2-yr period = 7,956 Total Item cost annualized over 30 yr pc period = 265 4 Surface Water Controls - Maintenance LS 2,300 1 2,300 5 Fence Repair LS 15 100 1,525 6 Mowing - Assume annual mowing for first 10 years of post -closure AC 1 40 39 Total Item Annual Cost for 10 mowing cost annualized mowing cost = events = over 30-yr 1,560 15,600 PC period = 520 7 Groundwater Monitoring - Semi-annual events EA 11 1,336 2 29,384 8 Groundwater Well Pump Repair / Maintenance LS 300 1 300 9 Gas Probe Monitoring, Maintenance and Reporting - 4 Events per Year EA 10 118 4 4,720 10 Leachate Monitoring - Annual EA 1 526 1 526 11 Leachate Depth Measurement - Semi-annual EA 1 1,472 2 2,944 12 Leachate Management - First 5 years of post- closure (managed on -site) (Note 2) Annual Total Total Item cost for leachate Item cost for cost annualized mgmt = 5-yr period = over 30-yr 20,000 100,000 PC period = 3,333 13 Gas Collection and Control Syst Maint LS 0 14 Gas Condensate. Disposal GAL 0 15 Subtotal - Items 1 through 14 55,681 16 Administrative Costs (% of Subtotal) 5% 2,784 17 Contingency (% of Subtotal) 10% 5,568 18 Total Cost per Year 64,033 19 Post -Closure Care Period: I 30 Years 20 Total Post -Closure Cost (in 2012 dollars) $1,920,995 21 Inflation adjustment factor for 2013 1.018 22 Inflation adjustment factor for 2014 23 Inflation adjustment factor for 2015 24 Inflation adjustment factor for 2016 Total Post -Closure Cost (adjusted to 2013 dollars - Line 20 x Line 21) $1,955,573 ores: 1 Unit cost for Item 3 is based on the Fertilizer, Soil Amendment and Seeding costs of the Closure Cost Estimate (Table 1) increased by a factor of 1.5 to provide an allowance for cover maintenace in addition to seeding, fertilizer and amendments. 2 Due to arid climate, leachate generation is not expected at closure. However, an annual allowance for leachate management is provided for the first 5 years of post -closure in the event of premature closure. APPENDIX C INSURANCE CERTIFICATE FOR CLOSURE AND POST -CLOSURE CARE COSTS 2013 CLOSURE AND POST -CLOSURE COST ESTIMATES The BRL Financial Assuarance Plan as revised March 2013 includes a closure cost estimate of $1,255,945 (Appendix A) and a post -closure cost estimate of $1,955,573 (Appendix B) for a combined total estimate of $2,469,351 (2012 dollars). These estimates are based on the site Closure and Post -Closure Plan revised March 2013. The accompanying insurance certificate reflects this adjusted amount. ACORD CERTIFICATE OF LIABILITY INSURANCE DATE(MM/20YYY) 03/20/2013 PRODUCER National Guaranty Insurance Company of Vermont 100 Bank Street, Suite 610 Burlington, Vermont 05401 (802) 864-1715 THIS CERTIFICATE IS ISSUED AS A MATTER OF INFORMATION ONLY AND CONFERS NO RIGHTS UPON THE CERTIFICATE HOLDER. THIS CERTIFICATE DOES NOT AMEND, EXTEND OR ALTER THE COVERAGE AFFORDED BY THE POLICIES BELOW. INSURERS AFFORDING COVERAGE NAIC # INSURED Waste Management of Colorado, Inc. 5500 South Quebec Street, Suite 250 Greenwood Village, Colorado 80111 INSURER A: National Guaranty Insurance Company INSURERB: of Vermont INSURERC: INSURER D: INSURER E: THE POLICIES OF INSURANCE LISTED BELOW HAVE BEEN ISSUED TO THE INSURED NAMED ABOVE FOR THE POLICY PERIOD INDICATED. NOTWITHSTANDING ANY REQUIREMENT, TERM OR CONDITION OF ANY CONTRACT OR OTHER DOCUMENT WITH RESPECT TO WHICH THIS CERTIFICATE MAY BE ISSUED OR MAY PERTAIN, THE INSURANCE AFFORDED BY THE POLICIES DESCRIBED HEREIN IS SUBJECT TO ALL THE TERMS, EXCLUSIONS AND CONDITIONS OF SUCH POLICIES. AGGREGATE LIMITS SHOWN MAY HAVE BEEN REDUCED BY PAID CLAIMS. INSR LTR ADD'/ IMSED TYPE OF INSURANCE POLICY NUMBER POLICY EFFECTIVE DATE(MM/OP/YY) POLICY EXPIRATION DATEIM /PD/YYl LIMITS GENERAL LIABILITY EACH OCCURRENCE $ COMMERCIAL GENERAL LIABILITY DAMAGE'TO-rtENTED PREMISES_(Ea c=re nee) $ ICLAIMS MADE (-1 OCCUR MED EXP (Any one person) S PERSONAL&ADVINJURY $ ................_......------ --�._ ..___. GENERAL AGGREGATE $ GEM'L AGGREGATE LIMIT APPLIES PER: PRODUCTS - COMP/OP AGG $ POLICY PRO- LOC AUTOMOBILE LIABILITY ANY AUTO COMBINED SINGLE LIMIT (Ea accident) A ALL OWNED AUTOS BODILY INJURY (Per parser)) H HIRED AUTOS NON -OWNED AUTOS BODILY INJURY (Per accident) PROPERTY DAMAGE (Per accident) GARAGE LIABILITY AUTO ONLY - EA ACCIDENT $ ANY AUTO OTHER THAN EAACC S AUTO ONLY: AGG S EXCESS/UMBRELLA LIABILITY EACH OCCURRENCE $ i i OCCUR I I CLAIMS MADE AGGREGATE $ $ DEDUCTIBLE S RETENTION S S WORKERS COMPENSATION AND EMPLOYERS' LIABILITY - I_WCSTATU- OTH- _�LORY UMIYS ER ANYPROPRIETOR/PARTNER/EXECUTIVE E.L. EACH ACCIDENT $ OFFICER/MEMBER EXCLUDED? If describe E.L. DISEASE - EA EMPLOYEE $ yes, under SPECIAL PROVISIONS below E DISEASE - POLICY LIMIT S A OTHER Closure Post -Closure CPCS02-0004 5/1/2002 4/9/2014 $1,255,945-00 $1.955,573.00 DESCRIPTION OF OPERATIONS / LOCATIONS /VEHICLES / EXCLUSIONS ADDED BY ENDORSEMENT/ SPECIAL PROVISIONS Buffalo Ridge Landfill, 11655 WCR 59, Keenesburg, CO 80643 This certificate certifies that the policy to which this certificate applies provides closure and/or post -closure care in connection with the Insureds obligation to demonstrate financial responsibility under Section 1.8.9 of the regulations pertaining to Solid Waste Disposal Sites and Facilities 6 CCR 1007-2, as amended. CERTIFICATE HOLDER CANCEL Director SHOULD ANY OF THE ABOVE DESCRIBED POLICIES BE CANCELLED BEFORE THE EXPIRATION Colorado Department of Public Health and Environment DATE THEREOF, THE ISSUING INSURER WILL%]O NAVIlgl S MAIL 120 DAYS WRITTEN Hazardous Materials/Waste Management Division NOTICE TO THE CERTIFICATE HOLDER NAMED TO THE LEFTmixtiodtocasocomosweenc 4300 Cherry Creek Drive South XDIRM x >aecx I� tinymy. Denver, Colorado 80246-1530 �itk\o I. � AUTHORIZED REPRESENTATIVE Donna L. Meals, Vice President an Secretary ACORD 25 (2001/08) OACORD CORPORATION 1988 CLOSURE/POST-CLOSURE PLAN BUFFALO RIDGE LANDFILL Weld County, Colorado Prepared by: Waste Management of Colorado, Inc. Buffalo Ridge Landfill 11655 WCR 59 Keenesburg, Colorado 80643 Reviewed By: \\p\q.117071/1///// REG�//i�� rFP�i 24176 Ft:ozi Thomas S. Sc weitzer, P&?<° ' ° �- - Registered Professional Er* State of Colorado License # 24176 Updated March 2013 CLOSURE/POST-CLOSURE PLAN BUFFALO RIDGE LANDFILL TABLE OF CONTENTS Section Page 1.0 INTRODUCTION 1 1.1 PURPOSE 1 1.2 FACILITY INFORMATION 1 2.0 CLOSURE PLAN 2 2.1 INTRODUCTION 2 2.1.1 Description 2 2.1.2 Regulatory Requirements 2 2.2 CLOSURE ACTIVITIES 3 2.3 MAXIMUM EXTENT OF OPERATIONS 5 2.4 FINAL COVER 5 2.4.1 Final Grades 5 2.4.2 Final Cover Description 5 2.5 CONSTRUCTION 6 2.6 CONSTRUCTION QUALITY ASSURANCE (CQA) 6 2.7 CLOSURE SCHEDULE 7 3.0 POST -CLOSURE PLAN 8 3.1 INTRODUCTION 8 3.1.1 Description 8 3.1.2 End Use 8 3.1.3 Regulatory Requirements 8 3.2 POST -CLOSURE ACTIVITIES 9 3.2.1 Facility Management 9 3.2.2 Post -Closure Activities 9 LIST OF FIGURES Figure 1 Site Location Map 2 Closure Area Map 3 Closure Schedule Closure/Post Closure Plan Updated March 2013 Buffalo Ridge Landfill CLOSURE/POST-CLOSURE PLAN t UFFALO RIDGE LANDFILL REVISION LOG DATE DESCRIPTION OF REVISION BY April 2002 General Plan review and update TSS/ARS March 2003 Update Plan to increase estimate of largest area of the landfill ever requiring final cover during the active life TSS/ARS March 2005 Update Plan and modify text in Sections 2.4, 2.5 and 2.6 to reflect approval of an alternative final cover design TSS/ARS March 2006 Revised to update soil cover quantities, reflect quarterly inspections for first 2 years of post -closure, and make miscellaneous text changes. TSS/ARS March 2007 Updated Plan to reflect changes to the corresponding Financial Assurance Plan dated March 2007 specifically replacing cost estimates prepared in 2002 with new cost estimates; updated soil backfill quantities. Miscellaneous text changes were also made to the Plan. TSS/ARS March 2009 Revised plan to update soil cover quantities, update largest area requiring closure, and reflect annual vegetative surveys during post -closure. JW August 2009 Amended plan to include pumping and closure of the temporary dewatering trench and to reference inclusion of asbestos disposal area fencing in closure cost. JW March 2010 Amended plan to update pumping for the temporary dewatering french and increase the fencing required for the asbestos disposal area in the closure cost. JW March 2011 Amended plan to update pumping for the temporary dewatering trench, add future landfill disposal cell Phase ld to be constructed in 2011, and fencing for the expanded asbestos disposal area. JW March201 2 Updated Plan to reflect changes to the corresponding Financial Assurance Plan dated March 2012, specifically replacing cost estimates prepared in 2007 with new cost estimates. Miscellaneous text changes were also made to the Plan. TSS March 2013 Updated to reflect changes in maximum area requiring 3'a party closure and amount of backfill required to meet 5% slopes. DN/TSS Closure/Post Closure Plan Buffalo Ridge Landfill Updated March 2013 1.0 INTRODUCTION 1.1 PURPOSE This Closure/Post-Closure Plan (Plan) for Buffalo Ridge Landfill (BRL) reflects the facility's present understanding of closure and post -closure care requirements for this solid waste disposal site. This Plan has been prepared to meet the following objectives: 1. Describe the steps necessary to close the site when the cost of closure would be the greatest. 2. Describe the activities to be conducted during the post -closure care period. This Plan has been prepared in accordance with the provisions of the Colorado "Regulations Pertaining to Solid Waste Disposal Sites and Facilities", 6 CCR 1007-2 (Regulations). Sections 2.5 and 3.5 of the Regulations pertain to closure activities and Sections 2.6 and 3.6 pertain to post - closure activities. This Plan is to be used in conjunction with the Financial Assurance Plan for BRL revised March 2013. Cost estimates are calculated in the Financial Assurance Plan for the closure and post - closure care activities described in this Plan. 1.2 FACILITY INFORMATION BRL is located approximately 5 miles north of Interstate Highway 76, on Weld County Road 59, in the southeast quarter of Section 34, Township 3 North, Range 64 West as shown on Figure 1. The facility is owned and operated by Waste Management of Colorado, Inc. (WMC). The site consists of 1,676 acres; 700 of which are permitted for municipal solid waste disposal with an approximate disposal capacity of 78 million bank cubic yards. The facility accepts non -hazardous municipal, commercial and industrial solid wastes. BRL will be developed in phases. The site will be closed and monitored as a single unit. Individual phases will not be closed or monitored separately. Therefore, this plan addresses the site as a whole. However, operational factors occurring during the life of the site may necessitate closure or monitoring of portions of the site individually. Closure/Post Closure Plan 1 Updated March 2013 Buffalo Ridge Landfill CLOSURE PLAN 2.1 INTRODUCTION 2.1.1 Description This Closure Plan (Plan) describes the steps necessary to close the facility at any point during its active life. This Plan will be reviewed and updated as needed for changing conditions. 2.1.2 Regulatory Requirements This Plan is prepared in accordance with Section 2.5, "Closure of Solid Waste Disposal Sites and Facilities" and Section 3.5, "Closure" of the Regulations. This Plan will be maintained in the facility operating record. The closure requirements call for a closure plan, a description of the closure activities and the closure certification. The requirements are summarized below: Closure Plan 1. Prepare a closure plan for approval by the CDPHE after consultation with the local governing body having jurisdiction. The plan, at a minimum, must include the following: a. The steps necessary to close the landfill at any point during its active life. b. A description of the final cover system and the methods and procedures to be used to install the cover. c. An estimate of the largest area of the landfill ever requiring a final cover during the active life. d. A schedule for completing closure activities. 2. Maintain a copy of the closure plan in the operating record. Closure Requirements 1. Close the site in accordance with the Solid Waste Disposal Sites and Facilities Act and the Regulations. 2. Sixty (60) days prior to closure, notify the CDPHE and the local governing body in writing that the facility will be closing. 3. Sixty (60) days prior to closure, notify the general public of the facility closure by posting clearly visible signs of suitable size at the site entrance. Closure/Post Closure Plan Buffalo Ridge Landfill 2 Updated March 2013 4. Enact precautions to prevent further use of the site for unauthorized disposal. 5. Prevent water pollution from occurring at or beyond the point of compliance. 6. Prevent nuisance conditions at or beyond the site boundary. 7. Initiate closure activities within thirty (30) days of reaching final design grades, unless an extension is obtained from CDPHE. 8. Complete closure within 180 days after closure initiation, or if necessary, obtain an extension from the CDPHE. Closure Certification 1. Following closure, submit a report certified by a Colorado professional engineer (RE.) to the CDPHE documenting that closure has been completed in accordance with the closure plan. Place a copy of the report in the facility operating record. 2. Following closure, record a notation on the deed or other title instrument stating that the land was used as a landfill and its use is restricted. Notify the CDPHE and the local governing authority that the notation has been recorded and place a copy of the notation in the operating record. 2.2 CLOSURE ACTIVITIES The following closure activities will be performed when site closure is necessary: 1. Construction Documents - Construction plans will be prepared. 2. Regulatory Agency Notification - Sixty (60) days prior to closure of any landfill phase, a notification of the intent to close will be submitted to the CDPHE and the local governing authority and a copy of the notice will be placed in the operating record. 3. Public Notification - Sixty (60) days in advance of closure date, signs will be placed at the entrance to the site notifying the general public of the closure date. 4. Final Cover - Final cover will be placed in accordance with the Regulations. The final cover design is discussed in Section 2.3 of this Plan. 5. Asbestos Disposal Area — On April 2, 2009, CDPHE approved the facility's Asbestos Waste Acceptance Plan for disposing friable asbestos waste at the site. The asbestos disposal area is located within the lined limits of the Phase 1 disposal cell in a fenced area Closure/Post Closure Plan Buffalo Ridge Landfill 3 Updated March 2013 with signage in accordance with the approved Waste Acceptance Plan. In the event of premature closure, Phase 1 (including the asbestos disposal area) will be covered with approximately 86,111 cubic yards of soil in order to achieve minimum final slopes of 5% per Section 2.4.1. Final cover will then be placed in accordance with Section 2.4.2. Facility closure will include the removal, replacement and surveying of the fencing of areas used for disposal of asbestos. Based on 3'a party cost estimates obtained for similar fencing at the Colorado Springs Landfill approximately $48,800 is estimated for removing and replacing approximately 3,200 feet of fencing. The post -closure cost estimate includes costs for facility inspections, maintenance and fence repair which allows for post -closure care for the asbestos disposal area. 6. Temporary Trench Collection System - During construction of the BRL Phase 1 c cell, an area of perched water was encountered in the vicinity of the permanent Phase 1 leachate sump. In order to continue construction and maintain compaction of the clay liner in the sump area, a temporary trench system was constructed. In a letter dated November 12, 2008, the CDPHE conditionally approved the design of the temporary trench system. Following construction, the trench system documentation report was sent to CDPHE and approved on March 6, 2009. The trench system collects artificially perched water and transports it away from the leachate sump area to a collection tank located outside the lined limits of Phase 1 c. This tank is monitored and pumped as necessary to allow for free flow of water from the saturated formation. Currently the tank capacity is reached approximately every 60 days based on current flow rates. The financial assurance includes closure of the trench system following completion of pumping. Based on the data collected to date, closure is anticipated to occur mid -2014. Pumping of the tank is expected to cost approximately $3,600 as included in the closure cost estimate. This estimate is based on pumping the tank once a month for the next year until closure. Each pumping event is estimated to cost $300, allowing a technician to drive to and from the site, pump the tank and document the activity. At completion of pumping, the trench system was designed to be abandoned in place, as could be the tank. However, based on abandoning the trench system in place and removing/backfilling the tank, the estimated closure cost is $25,100, which is included in the closure cost estimate. 7. Completion of Closure - Closure activities will be completed within 180 days following closure. A request for an extension may be submitted to CDPHE if climatic or operational factors dictate that additional time is required for proper closure. 8. Certification/Documentation - Upon completion of construction, a report will be prepared Closure/Post Closure Plan 4 Updated March 2013 Buffalo Ridge Landfill by a Colorado P.E. certifying that closure was conducted in accordance with the provisions of this plan. The report will be submitted to CDPHE and the local governing body for approval and will be placed in the operating record. To complete closure, a notation will be made on the title or deed to the land, which notifies prospective buyers that the land was used as a landfill, and that certain land use restrictions apply. Copies of the notation will be submitted to CDPHE and the local governing body and a copy will also be placed in the operating record. 9. Security - During closure activities and after closure, public disposal will be prohibited. Signs will be posted warning of unauthorized entry or waste disposal. The existing fence will be maintained and the front gate will be kept locked when not in use. 2.3 MAXIMUM EXTENT OF OPERATIONS An estimate of the largest area of the landfill requiring final cover is about 39 acres in Phase 1 as shown in Figure 2. Should the maximum area requiring final cover change, this Plan and the associated cover costs will be updated. 2.4 FINAL COVER 2.4.1 Final Grades Final grades have been designed to promote surface water runoff and minimize erosion. Final grade slopes are designed to be a minimum of 5 percent (20 to 1) and a maximum of 25 percent (4 to 1), unless alternative grades have been approved by CDPHE. Prior to placement of final cover, areas of the site that have not been filled to final grades may require placement of backfill to achieve 5% slopes. About 327,000 cubic yards of on -site soils are estimated for achieving minimum slopes prior to placement of final cover. 2.4.2 Final Cover Description BRL received approval from CDPHE and WCDPHE for an alternative final cover (AFC) design on August 26, 2004 and September 3, 2004 respectively. Accordingly, the AFC components are described below. 1. Alternative Final Cover Layer - The AFC layer will consist of a minimum of 18 inches of slightly compacted soil from on -site sources. AFC thickness on the side slope will be increased to 20 inches in accordance with the AFC design. The AFC components should have no less than 26% fines content and be compacted to between 80% to 90% of maximum density as determined by Standard Proctor (ASTM D 698). Approximately 110,000 cubic yards of soil will be necessary for the AFC layer. This conservatively assumes a 20 -inch AFC layer will be installed Closure/Post Closure Plan Buffalo Ridge Landfill 5 Updated March 2013 over the 31.1 -acre area. 2. Alternative Final Cover Topsoil Layer — The 6 -inch topsoil layer of the AFC will have no less than 30% fines content and be compacted to between 80% and 90% of maximum density as determined by Standard Proctor (ASTM D698). The 6 -inch topsoil layer of the AFC will be material suitable for sustaining vegetation. AFC seedbed preparation, seed mix and fertilizer requirements are specified in the approved "Buffalo Ridge Landfill Alternative Final Cover Demonstration" prepared by Golder Associates dated July 12, 2004. Approximately 32,000 cubic yards of soil will be required for the topsoil layer. 2.5 CONSTRUCTION Construction of the final cover system will be performed by using equipment such as scrapers to excavate, haul and place loose soil lifts for the AFC layer. A motor grader, low ground pressure dozer, or other suitable equipment will be used to spread/shape the cover. The topsoil layer will be placed loosely over the AFC layer with scrapers and then shaped with a motor grader, low ground pressure dozer, or other suitable equipment. The topsoil layer will then be prepared in accordance with specifications provided in the above referenced Buffalo Ridge Landfill Alternative Final Cover Demonstration. 2.6 CONSTRUCTION QUALITY ASSURANCE (CQA) To ensure proper implementation of the AFC design the following CQA requirements apply: ® Performance of grain -size distribution tests every 5,000 cubic yards will be conducted for the AFC layer and the 0.5 foot topsoil layer; ® Performance of Standard Proctor tests every 10,000 cubic yards; o In -situ density testing using a nuclear gauge at a frequency of one test per 1,000 cubic yards; o Oven -dry moisture contents at a frequency of one test every 1,000 cubic yards; ® Verification of proper thickness of cover at a grid spacing of about 100 feet on -center. A design drawing showing the area of AFC to be built and a detail of the cover cross-section will be supplied to the CDPHE and WCDPHE prior to construction. Also, an as -built construction drawing will be provided with the certification report that shows the survey points used to verify thickness on the approximately 100 feet on -center grid pattern. Closure/Post Closure Plan Buffalo Ridge Landfill 6 Updated March 2013 Upon completion of construction activities, a Colorado P.E. will sign a certification document indicating that the final cover was constructed in substantial conformance with the project specifications and approved closure plan. 2.7 CLOSURE SCHEDULE The schedule for closure is weather dependent. Excessive cold or rainy weather can affect placement of cover materials. The typical available construction window for placing cover materials in this climate is from late April through late September. A typical closure schedule is provided in Figure 3. If necessary, a request for an extension will be submitted to CDPHE to ensure that sufficient time is available to complete closure in accordance with the provisions of this closure plan. Closure/Post Closure Plan Buffalo Ridge Landfill 7 Updated March 2013 3.0 POST -CLOSURE PLAN 3.1 INTRODUCTION 3.1.1 Description This post -closure plan (Plan) describes all actions to be taken following closure of the site. Post -closure care begins after the site is closed in accordance with the Closure Plan. Post - closure care continues for a period of 30 years, unless during the life of the facility or the post -closure period, a demonstration is made to the CDPHE and the local governing body, which shows that a reduced time period is sufficient to protect human health and the environment. If the post -closure period is reduced, this Plan will be updated accordingly. 3.1.2 End Use Upon completion of closure, current plans indicate that the site will be zoned for agricultural use. This end use should have minimal impact on the fmal cover, and the use will not interfere with post -closure monitoring. 3.1.3 Regulatory Requirements This Plan is prepared in accordance with Section 2.6 "Post -Closure Care and Maintenance Standards" and Section 3.6, "Post -Closure Care and Maintenance" of the Regulations. This Plan will be maintained in the facility operating record. The regulatory requirements are summarized below: Post -Closure Plan 1. Prepare a post -closure plan for approval by CDPHE in consultation with the local governing body, which includes the provisions to prevent or minimize nuisance conditions, maintain the final cover, monitor groundwater, maintain and monitor the leachate collection system, and monitor landfill gas. 2. Describe the planned end use for the site and identify the name and address of a contact person who is responsible for the facility. 3. Maintain a copy of the post -closure plan in the site's operating record. Post -Closure Activities 1. The post -closure period shall be at least 30 years unless a demonstration is made to CDPHE and the local governing body that a shorter time period is sufficient to protect human health and the environment. 2. Permanent surface water structures remaining after closure shall be designed to Closure/Post Closure Plan Buffalo Ridge Landfill 8 Updated March 2013 manage run-on and run-off from a 100 -year, 24 -hour storm event as required. 3. Enact precautions to prevent water pollution at the point of compliance after closure. 4. Enact precautions to prevent nuisance conditions at or beyond the site boundary after closure. 5. Post -closure monitoring shall be conducted in accordance with the approved post -closure monitoring plan. 6. At the completion of the post -closure care period, a certification signed by a Colorado P.E. or an approval from CDPHE must be placed in the operating record verifying that post -closure has been completed in accordance with the post -closure plan. 3.2 POST -CLOSURE ACTIVITIES 3.2.1 Facility Management During the post -closure period, a facility manager will be named and a phone number and address for the manager will be incorporated into this plan. The manager currently responsible for the facility is: Mr. Jack Epple Buffalo Ridge Landfill 11655 WCR 59 Keenesburg, Colorado 80643 303-732-0218 3.2.2 Post -Closure Activities The following post -closure activities provide for inspection, maintenance, and monitoring of the design features of the facility during the post -closure period: 1. Inspections - Inspections of the entire site will typically be conducted quarterly for the first two years after closure and semi-annually thereafter. The inspector will assess the conditions of the site and recommend corrective actions for any items needing attention. Items to be inspected are further described in the following line items and include nuisance conditions, the final cover system, groundwater monitoring points, leachate monitoring system, gas monitoring system, surface water management system, and security. 2. Prevent Nuisance Conditions - The placement of final cover provides a barrier between the refuse and the environment. Construction of the final cover in Closure/Post Closure Plan Buffalo Ridge Landfill 9 Updated March 2013 substantial conformance with the project specifications should prevent disease vectors, deter birds, minimize odors, reduce blowing litter, and minimize air and water pollution as direct contact with refuse is prevented. Inspections and continued maintenance of the final cover system will ensure the integrity of the final cover so nuisance conditions are prevented throughout the post -closure period. The potential for on -site litter, traffic congestion, and noise pollution will be eliminated once the closure of the facility is complete since refuse will no longer be accepted for disposal and heavy equipment will no longer be operating. 3. Final Cover System - The maintenance of the final cover may involve repair of the AFC layer, the erosion layer and vegetation. It is estimated that 5% of the site per year will require cover maintenance, reseeding and fertilizer. An additional 5% is estimated, which will allow for 10% of the site for the first 2 years of post -closure for cover maintenance, reseeding and fertilizer. Additionally, a qualitative vegetation assessment is estimated to be performed annually during post -closure to ensure the vegetative cover is established and assist in identifying any areas that may require attention. 4. Groundwater Monitoring - Groundwater monitoring wells at BRL will be phased in with development of the landfill. A total of 20 groundwater -monitoring wells will be installed upon construction of the 6 landfill phases at BRL. The site currently has 11 groundwater monitoring wells, which make up the Phase 1 environmental monitoring system. The facility will be monitored in accordance with the Design and Operations Plan. The post -closure estimate assumes that 11 groundwater monitoring wells, which make up the Phase 1 environmental monitoring system, will be monitored during post -closure. Depending on the analytical data obtained during the site operating period, the number of wells and the monitoring frequency may be reduced during the post -closure care period with concurrence by CDPHE and the local governing authority. For this plan it is estimated that groundwater monitoring will be performed semi-annually. Samples will be analyzed for the constituents as listed in the approved Design and Operations Plan. The results of all analyses will be placed in the site's operating record. Monitoring results will be reviewed and a statistical evaluation performed comparing each event's results to background levels. Detection monitoring will continue as long as results remain below specified levels for each constituent. If the statistical evaluation shows that background levels are exceeded, confirmation sampling, and if necessary, corrective action will be performed in accordance with the Groundwater Monitoring Plan and this Plan will be updated as necessary. In addition to sampling, it is estimated that one well will require repair each year and a new pump will be required every five years. The integrity of the monitoring well Closure/Post Closure Plan Buffalo Ridge Landfill 10 Updated March 2013 system will be inspected during the monitoring events or during the annual site inspections. Any required repairs will be corrected. 5. Leachate Monitoring - The liquid elevation/level in the leachate collection sump will be monitored semi-annually to verify the levels are 1 foot or less above the liner. The measurements will be taken concurrent with semi-annual groundwater monitoring or site inspection activities. Leachate samples from the sumps will be taken annually for analysis, if leachate is present. Although leachate is not expected during post -closure, in the event that leachate is removed from a sump, it will be managed in accordance with the analytical data and approved leachate management procedures. Information related to the number of gallons removed, date, time, and location of leachate removal, and the disposal method will be maintained in the facility operating record. During the post -closure period, a demonstration may be made to the CDPHE showing that leachate no longer poses a threat to human health and the environment and that monitoring can cease. 6. Gas Monitoring - The facility will monitor gas at the site quarterly in accordance with the Design and Operations Plan. Landfill gas probes will be phased with development of the landfill. A total of 35 gas probes will be installed upon construction of the landfill. Currently, 10 gas probes are installed which make up the Phase 1 environmental monitoring system. The post -closure cost estimate assumes the 10 gas probes which make up the Phase 1 environmental monitoring system will be monitored during post -closure. Based on the monitoring data obtained during the site operating period, the number of probes and the frequency of monitoring may be reduced during the post -closure care period with concurrence by CDPHE and the local governing authority. Results from each gas monitoring event will be placed in the site's operating record. If monitoring results indicate that methane gas is present above the permissible regulatory limits, measures will be taken in accordance with Section 2.3.3 of the Regulations. 7. Surface Water Management System - Maintenance of the surface water management system is expected to be required during the post -closure period. This maintenance consists of regrading or desilting channels and ponds. In addition, semi-annual inspections will be conducted to ensure the stormwater system is functioning satisfactorily. Inspections of the permanent stormwater management structures will be conducted semi-annually and following storms exceeding the 100 year, 24 hour storm event. 8. Waste Disposal - Off -site refuse will not be accepted during the post -closure Closure/Post Closure Plan Buffalo Ridge Landfill 11 Updated March 2013 period. However, if during post -closure repairs, previously placed refuse is excavated for construction activities, the refuse will be placed within the permitted fill area and fmal cover will be applied. 9. Security- During post -closure, the perimeter fence will remain in place and the front gate kept locked when the site is not attended. Signs will be posted warning of unauthorized entry. The integrity of the fence will be monitored and maintenance performed as necessary. 10. Certification - Upon completion of the post -closure care period, notification will be given to the CDPHE certified by a registered Colorado P.E. or approved by CDPHE, verifying that post -closure care has been completed in accordance with this Plan. This notification will be placed in the operating record. 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Coley Avenue, Ste 310 ^ Centennial, CO 80111 -Phone (303) 771-9150 ^ Fax (303) 771-8776 123324 March 8, 2013 Mr. Doug Ikenberry Colorado Department of Public Health and Environment Hazardous Materials and Waste Management Division HMWMD-SWIM-B2 4300 Cherry Creek Drive South Denver, Colorado 80246-1530 RECEIVED HAS t 5 2013 Weld County ?Ia nning Department GREELEY OFFICE Mr. Troy Swain Weld County Department of Public Health and Environment 1555 N. 17th Avenue Greeley, Colorado 80631 RE: Buffalo Ridge Landfill, Keenesburg, Colorado Second Half 2012 Groundwater Monitoring Report Dear Mr. Ikenberry and Mr. Swain: On behalf of Waste Management of Colorado, Inc. (WMC), AquAeTer, Inc submits the second half 2012 groundwater detection monitoring results for the Buffalo Ridge Landfill (BRLF), in Keenesburg, Colorado. Regular semi-annual detection groundwater monitoring was completed in October 2012 at 11 monitoring wells. Enclosed is one copy laboratory analyticalreport for CDPHE, CDPHE. copyof the report for WCDPHE, and an electronic file containing There were no volatile organic compound detections and no statistical exceedances in any of the down -gradient monitoring wells during the second half 2012 event, and the BRLF remains in detection monitoring in accordance with 6 CCR 1007-2, Part 1 - Regulations Pertaining to Solid Waste Sites and Facilities (effective December 30, 2011). Furthermore, there are no outstanding Alternative Source Demonstrations (ASDs) for BRLF. If you have any questions pertaining to the groundwater detection monitoring program at BRLF, please contact Mr. Doc Nyiro at (720) 876-2621 or Mr. Bill Hedberg at (970) 686-2800. Sincerely, AquAeTer, Inc. 1 uw f kk *Q/i Terra Plute, E.I. Project Engineer cc: Mr. Mr. Mr. Mr. Mr. Mr. rv) Cathryn Stewart, P.G. Project Manager Kim Ogle, WCDPS, w/o enc. Louis Bull, Waste Management, w/ enc. Jack Epple, Waste Management, w/ enc. Bill Hedberg, Waste Management, w/ enc. Doc Nyiro, Waste Management, w/ enc. Tom Schweitzer, Waste Management, w/ enc. Cp-WWAval-t c a-hims 312-'7 / (3 go 13- 3gin W WASTE MANAGEMENT February 11, 2013 RECEIVED FEB 1 tl WELD COUNTY COMMISSIONERS Ms. Dana Podell Colorado Department of Public Health and Environment Air Pollution Control Division (APCD-SS-B1) 4300 Cherry Creek Drive South Denver, CO 80246-1530 RE: ANNUAL NMOC EMISSION RATE REPORT BUFFALO RIDGE LANDFILL AIRS ID 123/0448/001 Dear Ms. Podell: DENVER ARAPAHOE DISPOSAL SITE (DADS) PO Box 460397 3500 South Gun Club Ru(ad Aurora, CO 80046-0397 (720) 876-2620 (303) 690_SI 38 Fax RECEIVED FFR 1'`,Into Weld County Henning Department GREELEY OFFICE SENT BY UPS OVERNIGHT As required under the State Emissions Guideline Program for Municipal Solid Waste Landfills, Waste Management of Colorado, Inc. has completed an Annual NMOC Emission Rate Report for the Buffalo Ridge Landfill (BRIT) located at 11655 Weld County Road 59 in Keenesburg, Colorado for emissions through December 31, 2012. A Tier 2 investigation was conducted at the site in 2012 and the report is currently undergoing review by APCD. Following APCD's approval of the report, the NMOC concentration obtained in 2012 will be used in future NMOC reports. Please let me know if you have any questions about the report. Sincerely, G Doc Nyiro Environmental Engineer Attachment C,tyvtMu,u CUfiOIS ?13- O 1YP cc: Troy Swain, WCDPIIE Doug Ikenbel y, CDPIIE Kim Ogle, WCDPS Bruce Clabaugh, WMC Christian Colline, Waste Management Jack Epple, BRIT' Bill Hedberg, WMC Bill Myers, Waste Management Tom Schweitzer, WMC Rodney Walter, Waste Management 2012 TIER 1 NMOC EMISSION RATE REPORT BUFFALO RIDGE LANDFILL Prior to installation of a scale in December 2010, volume of waste accepted was estimated based on container size of incoming waste. Therefore, the equation found in 40 CFR 60.754(a)(ii) was used to determine NMOC emission rates for this Tier 1 NMOC Emission Rate Report. MNMoc=2LoR(e +ro-e-Nt)(CNMoc)(3.6 x 10 9) NMOC Emission Rate' 2012 MNM0C Lo R k c CNM0C Mass methane generation potential, m'/Mg Refuse methane generation potential, m3lMg = Average annual acceptance rate, Mg/yr Methane generation rate constant, 1/yr Years since closure, yrs (c = 0 for active and/or new landfills) Age of landfill, yrs Concentration of NMOC, ppm as hexane Conversion factor 170.00 Nan 2 = 37,490.87 We 0.02 Nde 2 0.00 10.50 4,000.00 Note 2 3.6 x 10-9 34.77 Mg/yr Information used to determine annual average acceptance rate The average annual acceptance rate (R) is determined by taking the total waste received between the approximate opening date of July 1, 2002 and December 31, 2010 divided by the number of years for this period less inert material. Waste in place (Mg) through 12/31/10 740,066 Waste in place less inert material (Mg) through 12/31/10 318,672 Percent inert material 569% Age of site at volume measurement 8.50 Annual average acceptance rate (Mg/yr) 37,490 87 Average Inert (from 7/1/02 to 12131/10) = 36.9% Soil (daily and intermediate) (4.1 refuse to soil) = 20.0% 2 For regulatory purposes, the EPA default values for k, Lo and CN,,,roc must be used to calculate Tier 1 NMOC emission rates unless actual values have been obtained during Tier 2 sampling. 3 Inert material includes inert wastes that are disposed in the landfill as well as daily and intermediate cover soil used as part of routine landfill operation. NOTE These calculations are made for NSPS purposes only EPA has specifically stated as follows 'It is recommended that these default values not be used for estimating landfill emissions for purposes other than NSPS and EG' (61 FR 9905, 9912, March 12, 1996). Consequently, these emissen calculations grossly overestimate actual and potential emissions and reviewers of this document are specifically cautioned against improper and irresponsible uses of these calculations Page 1 of 2 2012 TIER 1 NMOC EMISSION RATE REPORT BUFFALO RIDGE LANDFILL 40 CFR 60.754(a) provides two equations for determining NMOC emission rates; one for sites with known solid waste acceptance rates and another for sites with unknown (i.e. estimated) waste acceptance rates. For sites that include time periods with both known and unknown acceptance rates, the Regulation indicates that both equations should be used. Buffalo Ridge Landfill is such a facility. NMOC Emission Rate Calculations for Years with Known Waste Acceptance Rates The site installed scales in Decmeber 2010. Therefore, the equation found in 40 CFR 60.754(a)(1)(i) for known waste acceptance was used to determine NMOC emission rates for this time period. The equation is provided below: NMOC Emission Rate1 MNMoc = Summation of [2kL0Mi(e ktl)(CN„,oc)(3.6 x 1 Ds)] for each year with a known waste acceptance rate MNMOC = Mass emission rate of NMOC, Mg/yr k = Methane generation rate constant, 1/yr 0.02 t Le = Refuse methane generation potential, m'/Mg = 170.00 2 M, = Mass of solid waste received for given year, Mg = Varies per year (see table below) t, = Age of the i n section, Years current year minus year of waste placement CNMOC = Concentration of NMOC, ppm as hexane 4000.00 2 Conversion factor = 3.6 x 10.9 NMOC Emission Rate Calculation Summary (for years with known waste acceptance rates) Tons Tons Less Year Received % Inert Inert Waste' Mi* tl Meroc 2011 67,947 59.8% 27,301 24,767 1 2.38 2012 187,169 43.4% 106,024 96,184 0 9.42 2013 2014 Totals 255,136 133,325 120,952 11.80 Mg/yr 'Conversion Used: tons to Mg - divide tons by 1.1023 1 For landfills in areas with a thirty year annual average precipitation of less than 25 inches, a k value of 0.02 is to be used. According to weather data, annual precipitation in the area of Buffalo Ridge Landfill is about 16 inches, therefore a k value of 0.02 has been used in the NMOC emission rate calculation. 2 For regulatory purposes, the EPA default values for Lo and CNMoc must be used to calculate Tier 1 NMOC emission rates unless actual values have been obtained during Tier 2 sampling. 40 CFR 60.754{a) allows the mass of nondegradable solid waste to be subtracted from the total mass of solid waste when calculating the value of Mi if documentation of the nature and amounts of such wastes is maintained. NOTE These calculations are made for NSPS purposes only. EPA has specifically stated as follovs"It is recommended that these default values not be used for estimating landfill emc>;ions for purposes other than NSPS and EG' (61 FR 9905, 9912, March 12, 1996). Gonsequenty, these emission calculations grossly overestimate actual and potential emissions and reviewers of this document are specifically cautioned against Improper and Irresponsible uses of these calculations. TOTAL NMOC EMISSION RATE: NMOC rate for years with known waste acceptance rates: 11.80 NMOC rate for years with estimated waste acceptance rates: 34.77 Combined NMOC Emission Rate: 46.56 Mg/yr Page 2 of 2 W WASTE MANAGEMENT WASTE MANAGEMENT CERTIFICATION STATEMENT NOTE: This Certification must be completed by a responsible official for any application, report, document, or compliance certification submitted to the Air Pollution Control Division pursuant to Colorado Regulation No. 3 and General Conditions of the Operating Permit. A Certification Statement must be kept with each associated report or document submittal. OPERATING PERMIT NUMBER: COMPANY NAME: FACILITY NAME: FACILITY ADDRESS: Purpose of Certification: AIRS ID 123/0448/001 Waste Management of Colorado, Inc. Buffalo Ridge Landfill 11655 Weld County Road 59, Keenesburg, CO 80643 2012 Annual NMOC Report "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." Bruce Clabaugh Print Name Environmental Protection Manager Title Enn-nva January 16, 2013 Mr. Doug Ikenberry Colorado Department of Public Health and Environment I Iazardous Materials and Waste Management Division 4300 Cherry Creek Drive South Denver, CO 80246-1530 RECEIVED FEB 1 . 2C13 WELD COUNTY cO1MMISSIONERS E -n BEFITYES eLPAC19O - rknF r'nc !M. san: QD9-1k2SE P(� Roy 4oO391 F,00 NP. U I1 Gun( ]PICA (:c ,iia tO L39l (12) ORS-'(1'�' l 1C s) 6oki,. RE: Buffalo Ridge Landfill Leaehate Management Plan Response to Comment Letter Dated August 30, 2012 Dear Mr. Ikenberry: RECEIVED .IAM 21 2013 Weld County Pianm.;o popallryi�nt GREELEY OFFICE Waste Management of Colorado, Inc. (WMC) received your letter dated August 30. 2012 providing comments on the Buffalo Ridge Landfill (BRIT) Leachate Management Plan and the accompanying cover letter. The comments from your letter are restated below with our responses following each comment. January' 9, 2012 Letter Comment #1 — Response ill indicates that Waste Management intends to include the approved Leachate Management Plan as an appendix to a revised Engineering Design and Operations Plan (ED(R). In this instance, the Division will consider the above referenced Leachate Management Plan as a proposed supplemental amendment to the currently approved EDOP. It is the Division's position that the last paragraph of Section 7.1.1 of the Engineering Design and Operations Plan (EDOP revised December 10, 1992) be replaced with a proper reference to the leachate management plan that is approved (or approved with conditions) by Weld County and the Division, as the case may be. The Division views the page replacement as a minor modification to the EDOP and therefore would not require a public comment period. Response #1 -- Ilpon approval of the Leachate Management Plan the last paragraph of Section 7.1.1 of the EDOP will be revised to include a reference to the approved Leachate Management Plan. @am{ Ca O/ S O -)D-13 a -o l 3 - o Yl cc ?Log�i Leachate Management Planfrevised January 2012) Comment #2 — Based on the Division's August 3, 2012 teleconference with Waste Management representatives, we acknowledge that references to storage of leachate in above ground tanks located over lined portions of the landfill will be removed from the plan. Response #2 — References to storage of leachate in above ground tanks located over lined portions of the landfill have been removed from the plan. Comment #3 — Item 3, 1" sentence — Change the sentence to state, "In the event the leachate is determined to be non -hazardous, it may he used for dust control within the lined limits of the landfill on finished decks and interior slopes that are without final cover." Response #3 --'fhe sentence has been revised as requested. Comment #4 — Item 4.. Is' sentence — Change "would" to "shall". Response #4 — The sentence has been revised as requested. Comment #5 — Item 4, last sentence — Change the sentence to state, "In lieu of a water truck, an alternative method for transporting and applying the leachate shall be submitted to Weld County and CDPI-113 for review and approval." Response #5 - The sentence has been revised as requested. Comment #6 - - Item 5, only sentence — Change the sentence to state. "The leachate shall he applied on adequate cover composed of soils using application rates that wall not cause runoff or standing liquid." Response #6 -- 'the sentence has been revised as requested. Comment #7 — Item 6, only sentence --- Insert "leachate" between "The" and "application. Response #7 — The sentence has been revised as requested Comment #8 — Item 7, 2nd bullet -- Change the text to state, "The leachate analytical results along with the supporting laboratory reports, and." Response #8 -- The sentence has been revised as requested. Comment #9 — Item 7, 3rd bullet — Change the text to state, "The dates and volumes of leachate pumped and applied on site." Response #9 — The sentence has been revised as requested. Comment #10 — item 7 — Add a fourth bullet that states, "The general location(s) where leachate was applied the previous calendar year." Response #10 — The sentence has been revised as requested. If you have any questions about these responses or the attached plan, please call me at 720-876- 262I. Sincerely, • I)oc Nyiro Environmental Engineer Attachment cc: Jack Epple, Buffalo Ridge l:andlill Bill Hedberg, Buffalo Ridge Landfill Kim Ogle, WCI)PS Toni Schweitzer, WMC Troy Swain, WCDPHE Rodney Walter, Waste Management 1,EACEIATE MANAGEMENT PLAN BUFFALO RIDGE I,ANDFILI, January 2013 The disposal cell design includes a leachate collection system that underlies the waste disposal area. The drainage blanket is designed and constructed to drain to sump areas located at the low point of each disposal area. "the permanent sumps are designed with riser pipes that extend up the side -slope of the disposal cell to ground surface. The riser pipes arc used for monitoring leachate levels, collecting samples for analysis, and removing leachate as required. The management method to be implemented at the Buffalo Ridge Landfill includes the following: L 'temporary and permanent sump risers shall be monitored at least quarterly for the presence of leachate. Monitoring shall be conducted to verify that leachate levels remain below one foot above the floor of the liner adjacent to the sump. Leachate shall be removed as necessary to maintain leachate levels at or below one foot above the floor of the liner adjacent to the sump. 2. Leachate shall he sampled and analyzed at least annually. The leachate parameters and constituents shall include those listed in Appendix 1 A and 1B of the Regulations Pertaining to Solid Waste Sites and Facilities, 6 CCR 1007-2. "the list of parameters and constituents is subject to revision pending the acceptance of future waste streams at the landfill (e.g., Technologically Enhanced Naturally Occurring Radioactive Material, etc.). In the event the leachate is determined to be a hazardous waste, it shall be disposed of in accordance with all applicable laws, regulations and ordinances. 3. In the event the leachate is determined to be non -hazardous, it may be used for dust control within the lined limits of the landfill on finished decks and interior slopes that are without final cover. If alternative on -site leachate disposal methods are proposed, a request shall he submitted to Weld County and the Colorado Department of Public I lealth and Environment (CDPTIF) for review and approval. 4. When using leachate for dust control, leachatc shall be pumped from the sumps into a water truck for transport to the disposal area. A spray -bar attachment on the truck, or similar distribution device, will he used to apply the leachate. In lieu of a water truck, if an alternative method for transporting and applying the leachate is proposed, a request shall be submitted to Weld County and CDPIIE for review and approval. 5. 'the leachate shall be applied on adequate cover composed of soils using application rates that will not cause runoff or standing liquid. 6. The leachate application areas will be located away from the active disposal area. Page 1 7. The following information shall be provided to Weld County and the CDPHE with the First I alf Groundwater Monitoring Report each year: o The dates and results of the quarterly leachate level monitoring, e The leachate analytical results along with the supporting laboratory reports, • The dates and volumes of leachate pumped and applied on site, o The general location(s) where leachate was applied the previous calendar year. Page 2 STATE OF COLORADO John W. Hickenlooper, Governor Christopher E. Urbina, MD, MPH Executive Director and Chief Medical Officer Dedicated to protecting and improving the health and environment of the people of Colorado 4300 Cherry Creek Dr. S. Denver, Colorado 80246-1530 Phone (303) 692-2000 Located in Glendale, Colorado http://www.cdphe.state.co.us January 28, 2013 Laboratory Services Division 8100 Lowry Blvd. Denver, Colorado 80230-6928 (303) 692-3090 Mr. Doc Nyiro Waste Management Denver Arapahoe Disposal Site 3500 S. Gun Club Road Aurora, CO 80018 RECEIVED r:n 0 1 2013 Weld County viauniug Departmint GREE EY OFFICE Colorado Department of Public Health and Environment Re: Approval of Buffalo Ridge Landfill (BRLF) Leachate Management Plan (Revised January 2013) attached to a Waste Management Cover Letter dated January 23, 2013 Dear Mr. Nyiro, The Hazardous Materials and Waste Management Division (Division) of the Colorado Department of Public Health and Environment reviewed the above referenced Leachate Management Plan (Revised January 2013) that was attached to your cover letter dated January 23, 2013. Additionally, the Division reviewed a Leachate Management Plan (Revised January 2013) that was attached to your cover letter dated January 16, 2013. In consultation with the Weld County Department of Public Health and Environment, the Division approves the (BRLF) Leachate Management Plan (Revised January 2013) attached to your January 23, 2013 cover letter. However, please be advised that the previous test parameters for the leachate, which were adopted into the associated Weld County Use By Special Review Permit, have been superseded in the Leachate Management Plan (Revised January 2013). Accordingly, Weld County staff may be subject to input from Weld County elected officials (i.e., local governing body) concerning this matter. As per Response #1 of your January 16, 2013 letter, upon approval of the Leachate Management Plan by Weld County, please submit the revised page(s) to the approved Engineering Design and Operations Plan (EDOP revised December 10, 1992) that contains a proper reference to the approved leachate management plan in the last paragraph of Section 7.1.1 of the EDOP to Weld County and the Division for review and approval. In closing, the Division is authorized to bill for its review of technical submittals pursuant to Section 1.7 of the Regulations Pertaining to Solid Waste Sites and Facilities, 6 CCR 1007-2. An invoice for the Division's review of the above referenced documentation will be sent under separate cover. Wm YR,,c vt,`( CamS 2TD\3a 0.39 cc Mr. Doc Nyiro January 28, 2013 Page 2 of 2 Please contact me at 303-692-3389 if you have any questions. Sincerely, a-1,4744 cxt aste4,1 Douglas M. Ikenberry Solid Waste and Material Management Unit Solid and Hazardous Waste Program Cc: Troy Swain, Weld County Department of Public Health and Environment Kim Ogle, Weld County Department of Planning Services Tom Schweitzer, P.E., Waste Management Bill Hedberg, Waste Management FILE: SW WLD BRL 2.2 LEACI LATE MANAGEMENT PLAN BUFFALO RIDGE LANDFILL January 2013 The disposal cell design includes a leachate collection system that underlies the waste disposal area. The drainage blanket is designed and constructed to drain to sump areas located at the low point of each disposal area. The permanent sumps are designed with riser pipes that extend up the side -slope of the disposal cell to ground surface. The riser pipes are used for monitoring leachate levels, collecting samples for analysis, and removing leachate as required. The management method to be implemented at the Buffalo Ridge Landfill includes the following: 1. Temporary and permanent sump risers shall be monitored at least quarterly for the presence of leachate. Monitoring shall be conducted to verify that leachate levels remain below one foot above the floor of the liner adjacent to the sump. Leachate shall be removed as necessary to maintain leachate levels at or below one foot above the floor of the liner adjacent to the sump. 2. Leachate shall be sampled and analyzed at least annually. The leachate parameters and constituents shall include those listed in Appendix 1 A and 1I3 of the Regulations Pertaining to Solid Waste Sites and Facilities, 6 CCR 1007-2. The list of parameters and constituents is subject to revision pending the acceptance of future waste streams at the landfill (e.g., Technologically Enhanced Naturally Occurring Radioactive Material, etc.). In the event the leachate is determined to be a hazardous waste, it shall he disposed of in accordance with all applicable laws, regulations and ordinances. 3. In the event the leachate is determined to be non -hazardous, it may be used for dust control within the lined limits of the landfill on finished decks and interior slopes that arc without final cover. Should there be more non -hazardous leachate than needed for dust control, it shall be properly transported and managed (such as disposal at a publicly owned wastewater treatment facility). If alternative on -site leachate disposal methods are proposed, a request shall be submitted to Weld County and the Colorado Department of Public Health and Environment (CDPHE) for review and approval. 4. When using leachate for dust control, leachate shall be pumped from the sumps into a water truck for transport to the disposal area. A spray -bar attachment on the truck, or similar distribution device, will be used to apply the leachate. In lieu of a water truck, if an alternative method for transporting and applying the leachate is proposed, a request shall he submitted to Weld County and CDPI IF for review and approval. 5. The leachate shall be applied on adequate cover composed of soils using application rates that will not cause runoff or standing liquid. Page 1 6. The leachate application areas will be located away from the active disposal area. 7. The following information shall be provided to Weld County and the CDPHP, with the First Half Groundwater Monitoring Report each year: • The dates and results of the quarterly leachate level monitoring, • The leachate analytical results along with the supporting laboratory reports, • The dates and volumes of leachate pumped and applied on site, • The general location(s) where leachate was applied the previous calendar year. Page 2 W WASTE MANAGEMENT January 23, 2013 Mr. Doug Ikenberry Colorado Department of Public Health and Environment Hazardous Materials and Waste Management Division 4300 Cherry Creek Drive South Denver, CO 80246-1530 RE: Buffalo Ridge Landfill Leachate Management Plan Response to Verbal Comments on January 23, 2013 Dear Mr. Ikenberry: DENVER ARAPAHOE DISPOSAL SITE (DADS) PO Box 460397 • Q, 5oud; t_3u:: Club Road Au',Ufa. (,1.) `2l4-C3`i7 (72211 876-1620 (303i 690-8136 Fax Waste Management of Colorado, Inc. (WMC) is submitting this revised Leachate Management Plan (Plan) for the Buffalo Ridge Landfill based on our discussion today concerning Item 3 in the Plan. A portion of the second sentence from the January 2012 Plan was inadvertently deleted from the Plan that was submitted on January 16, 2013. The deleted wording has been reinserted into the attached revised Plan. If you have any questions about the revision, please call me at 720-876-2621. Sincerely, 159, Doc Nyiro Environmental Engineer Attachment cc: Jack Epple. Buffalo Ridge Landfill Bill Hedberg, Buffalo Ridge Landfill Kim Ogle, WCDPS Tom Schweitzer, WMC Troy Swain, WCDPHE Rodney Walter, Waste Management ® cLi ( DPW ,' . fZ5.17A 2013-0396 ✓ 2 2/ Hello