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HomeMy WebLinkAbout9702-GasMonitoringPlan-20120711 2211 W. Meadowview Rd Suite 101 Greensboro, NC 27407 tel: 336/323-0092 fax: 336/323-0093 www.JoyceEngineering.com July 11, 2012 Brian Wootton, Hydrogeologist Solid Waste Section Division of Waste Management 1646 Mail Service Center Raleigh, NC 27699-1646 Re: Dan Johnson Landfill (#97-02) Landfill Gas Monitoring Plan Revision Request Wilkes County, NC Dear: Mr. Wootton Responses to the comments received on July 10th, 2012 are bulleted below each corresponding comment in bold italic text. 1. Within ninety (90) days of approval of the landfill gas monitoring plan by the Solid Waste Section (SWS), the new gas monitoring wells shall be installed at the proposed locations as depicted on the site drawings.  Statement added to Section 1.0 2. A Professional Engineer (P.E.) or a N.C. Professional Geologist (L.G.) must certify/ supervise the installation of all landfill gas monitoring wells.  Statement added to Section 2.1 3. Each constructed landfill gas monitoring well must be surveyed for location and elevation by a North Caroling Registered Land Surveyor.  Revised Section 7.0 4. Within thirty (30) days of completion of the landfill monitoring gas wells, a well construction record and/or boring log and a diagram for each well, including but not limited to total depth, screened interval and distance above seasonal table must be submitted to the SWS. The submittal must also include a scaled topographic map showing the surveyed location and identification of new, existing and abandoned landfill gas monitoring wells.  Statement added to Section 2.1 Mr. Brian Wootton July 11, 2012 Page 2 of 2 The revised landfill gas monitoring plan must be signed, sealed, and dated by a N. C. Professional Engineer (P.E.) or a N.C. Professional Geologist (L.G.) and submitted to the SWS section for approval within thirty (30) days of the date of this letter. Once approved by the SWS, construction of gas monitoring wells/reporting criteria and subsequent sampling of gas monitoring wells may commence according to the gas monitoring plan.  The Landfill Gas Monitoring Plan has been revised according to the above comments and has been sealed and signed by an N.C. Professional Engineer. Sincerely, JOYCE ENGINEERING, INC. Heather Wilburn, E.I.T Project Consultant PREPARED FOR: WILKES COUNTY DEPARTMENT OF SOLID WASTE 9219 ELKIN HIGHWAY ROARING RIVER, NORTH CAROLINA 27298 DAN JOHNSON LANDFILL PERMIT NO. 97-02 LANDFILL GAS MONITORING PLAN JUNE 2012 REVISED JULY 2012 PREPARED BY: 2211 WEST MEADOWVIEW ROAD, SUITE 101 GREENSBORO, NORTH CAROLINA 27407 NC LICENSE NUMBER C-0782 PHONE: (336) 323-0092 FAX: (336) 323-0093 JOYCE PROJECT NO. 356.1102.12, TASK NO. 01 Landfill Gas Monitoring Plan Joyce Engineering, Inc. Wilkes County Dan Johnson Landfill, Permit No. 97-02 Revised July 2012 i LANDFILL GAS MONITORING PLAN Dan Johnson Landfill Permit No. 97-02 TABLE OF CONTENTS 1.0 INTRODUCTION...........................................................................................................1 1.1 Background .....................................................................................................................1 1.2 Site Geology and Hydrogeology .....................................................................................1 1.3 Regulatory Limits ...........................................................................................................1 2.0 LANDFILL GAS MONITORING ................................................................................1 2.1 Landfill Gas Monitoring Network .................................................................................2 2.2 Structure and Ambient Sampling .................................................................................2 2.3 Landfill Gas Monitoring Frequency .............................................................................3 3.0 LANDFILL GAS SAMPLING PROCEDURES .........................................................3 3.1 Detection Equipment ......................................................................................................3 3.2 Landfill Gas Sampling Procedure .................................................................................3 4.0 RECORD KEEPING AND REPORTING ...................................................................4 4.1 Landfill Gas Monitoring Data Form .............................................................................4 4.2 Sampling Reports ............................................................................................................4 4.3 Permanent Record Keeping ...........................................................................................4 5.0 CONTINGENCY PLAN ................................................................................................4 6.0 CERTIFICATION OF PROFESSIONAL GEOLOGIST OR ENGINEER .............5 7.0 CERTIFICATION OF REGISTERED LAND SURVEYOR ....................................5 8.0 REFERENCES ................................................................................................................5 Drawing Drawing LFG-1 Landfill Gas Monitoring Plan Appendices Appendix I Solid Waste Section – Landfill Gas Monitoring Guidance Appendix II Landfill Gas Monitoring Data Form Appendix III Landfill Gas Monitoring Well Detail Appendix IV Certification of Professional Geologist or Engineer Landfill Gas Monitoring Plan Joyce Engineering, Inc. Wilkes County Dan Johnson Landfill, Permit No. 97-02 Revised July 2012 1 1.0 INTRODUCTION This Landfill Gas Monitoring Plan (LGMP) will serve as a guidance document for collecting and monitoring of landfill gas at the Wilkes County Germantown Landfill. Landfill gas will be monitored quarterly to ensure that methane concentrations do not exceed the regulatory limit at the facility boundary or in facility structures. The LGMP was prepared in accordance with the North Carolina Department of Environment and Natural Resources (NC DENR) Division of Waste Management Solid Waste Section Landfill Gas Monitoring Guidance document, to assure performance standards are met and to protect public health and the environment. Within ninety (90) days of approval of the landfill gas monitoring plan by the Solid Waste Section (SWS), the new gas monitoring wells will be installed at the proposed locations as depicted on the site drawings. 1.1 Background The Dan Johnson Landfill is a closed, unlined municipal solid waste (MSW) landfill maintained by Wilkes County. The landfill property is located near the town of Austin, North Carolina. The surrounding area is primarily residential/agricultural and contains open fields and woodlands. The landfill is bounded to the south and east by an unnamed tributary of Little Elkin Creek. 1.2 Site Geology and Hydrogeology The Dan Johnson Landfill is located in the Blue Ridge Belt in the Aligator Back Formation. It consists of laminated to thin layered mica schist and phyllite interlayered with biotite, muscovite, gneiss and amphibolite. 1.3 Regulatory Limits Closed, unlined MSW landfill requirements are governed by the 15A NCAC 13B 500 rules and regulations for sanitary landfills. Current regulations state that concentration of methane gas generated by the facility should not exceed 25 percent of the lower explosive limit (LEL) for methane in facility structures or that the concentration of methane gas does not exceed the LEL for methane at the facility property boundary. The LEL for methane equals 5% by volume at standard temperature and pressure. This LGMP prescribes a routine methane monitoring program to ensure standards are met and actions to be taken if methane concentrations exceed specified limits. 2.0 LANDFILL GAS MONITORING Gas monitoring at the Dan Johnson Landfill has been performed throughout the post-closure care period. Quarterly monitoring has been conducted on the landfill property with the use of bar- hole probes. This site is one of three Wilkes County landfill sites that Joyce Engineering monitors. Germantown Road Landfill is the other closed site and Roaring River is their current, active landfill site. Common practice for the Wilkes County landfill sites will be to monitor the first and third quarterly gas events on one calendar day and the second and fourth quarterly gas Landfill Gas Monitoring Plan Joyce Engineering, Inc. Wilkes County Dan Johnson Landfill, Permit No. 97-02 Revised July 2012 2 events will occur in conjunction with the semi-annual groundwater monitoring events usually over a two day period. 2.1 Landfill Gas Monitoring Network The locations of the proposed network of landfill gas monitoring wells are shown on Drawing No. 1. The proposed network will consist of 3 wells (GW-1, GW-2, and GW-3) to be installed to depths above groundwater. The landfill gas monitoring wells are currently proposed to be located at the facility’s northern boundary. GW-1 is proposed in the northwest corner of the property, GW-2 is proposed to be adjacent to the facility’s entrance and GW-3 is proposed to be place approximately 500 feet east of GW-2. Note that the Dan Johnson Landfill is bordered by an unnamed tributary of the Little Elkin Creek located to the south and east. The tributary acts as a hydraulic barrier to the movement of subsurface landfill gas. Therefore, no landfill gas monitoring wells have been proposed for the southern and eastern portions of the property. The future landfill gas wells will be constructed and installed to the specifications listed in 15A NCAC Subchapter 2C and the Solid Waste Section’s Landfill Gas Monitoring Guidance Document. A Professional Engineer (P.E.) or a N.C. Professional Geologist (L.G.) must certify/ supervise the installation of all landfill gas monitoring wells. A detailed example of a typically constructed LFG well is included in Appendix III. Proposed Monitoring Well Summary Well ID Monitoring Status Total Depth (ft) Screen Interval (ft) Depth to GW (ft) Lithology *GW-1 Proposed 30 5-30 30 Soil/Saprolite *GW-2 Proposed 30 5-30 30 Soil/Saprolite *GW-3 Proposed 30 5-30 30 Soil/Saprolite * Total depths, screen intervals, and depth to water table are estimates based on available topographic information, common engineering practices and field log data from adjacent groundwater monitoring wells. Values will be updated after well completion. Within thirty (30) days of completion of the landfill monitoring gas wells, a well construction record and/or boring log and a diagram for each well, including but not limited to total depth, screened interval and distance above seasonal table will be submitted to the SWS. The submittal will also include a scaled topographic map showing the surveyed location and identification of new, existing and abandoned landfill gas monitoring wells. 2.2 Structure and Ambient Sampling There are no structures being monitored at this facility. Landfill Gas Monitoring Plan Joyce Engineering, Inc. Wilkes County Dan Johnson Landfill, Permit No. 97-02 Revised July 2012 3 2.3 Landfill Gas Monitoring Frequency The landfill gas wells included in this LGMP will be monitored at least quarterly in accordance with current regulations. The first and the third quarterly monitoring events will occur sometime in January and July. The gas wells will be monitored for the second and fourth quarterly events in conjunction with the semi-annual groundwater monitoring events which usually occur in April and October. 3.0 LANDFILL GAS SAMPLING PROCEDURES Landfill gas samples will be collected in accordance with Solid Waste Section’s Landfill Gas Monitoring Guidance document. Details of detection equipment and sampling procedures are outline below. 3.1 Detection Equipment A portable combustible gas monitor, measuring the concentration of combustible gases in units of percent of LEL, shall be used to conduct gas monitoring. The LEL means the lowest percent by volume of a mixture of combustible gas in air that will propagate a flame at 25 degrees Celsius and atmospheric pressure. The gas monitor shall be calibrated to methane using the manufacturer's calibration kit and procedure before the monitoring activities begin. The calibration gas to be used is depends on the expected levels of methane in landfill gas monitoring wells. If low level methane is expected 15% CO2/15% CH4 calibration gas should be used; while if high level methane is expected, 35% CO2/ 50% CH4 calibration gas should be used. Verification that the equipment was calibrated in accordance with the manufacture’s specifications is required. Calibration information must be recorded on the Landfill Gas Monitoring Data Form. 3.2 Landfill Gas Sampling Procedure The portable combustible gas monitor will be turned on and allowed to warm up prior to gas sampling. The static pressure should show a reading of zero before taking the initial sample. The sample tube shall be purged for at least one minute prior to connecting the sample tube to the detection well, and then the initial concentration will be recorded. Gas monitoring will continue until the reading has stabilized. A stable reading is considered to be +/- 0.5% by volume on the instrument’s scale. Once the reading has stabilized for 5 seconds, the reading will be recorded and the tubing will be disconnected from the valve. These steps will be repeated for each landfill gas monitoring well. Landfill Gas Monitoring Plan Joyce Engineering, Inc. Wilkes County Dan Johnson Landfill, Permit No. 97-02 Revised July 2012 4 4.0 RECORD KEEPING AND REPORTING The landfill gas data will be recorded in accordance to the SWS’s Landfill Gas Monitoring Guidance document included as Appendix I. The records will be maintained in the landfill operating record. 4.1 Landfill Gas Monitoring Data Form A landfill gas monitoring data form is included as Appendix II. 4.2 Sampling Reports The landfill gas monitoring report will be prepared in accordance with the NC DENR Division of Waste Management Solid Waste Section Landfill Gas Monitoring Guidance document. The report will describe the method of sampling, the date, time, location, sampling personnel, atmospheric temperature, reported barometric pressure, equipment calibration information, exceptions noted during sampling, and general weather conditions at the time of sampling, in addition to the concentration of combustible gases. 4.3 Permanent Record Keeping A copy of the landfill gas monitoring results and any remediation plans will be maintained in the landfill operating record. The reports will be maintained at an alternative location near the facility approved by the Division. 5.0 CONTINGENCY PLAN If methane gas levels that exceed the regulatory limits are detected, the results shall be reported to Wilkes County immediately. The County will notify the NCDENR, SWS in writing and will take immediate steps to ensure safety and protection of human health. If methane levels exceed the LEL in existing gas wells, the need for additional gas wells will be evaluated, as well as the need for monitoring within any nearby structures in the direction of the gas migration. If the exceedance is in a gas well not located at or near a property boundary, additional investigation including use of bar-hole probes or temporary gas wells may be implemented to determine whether or not the exceedance extends to the property boundary. If necessary, additional permanent gas wells may be installed between the exceeding well(s) and the property boundary to demonstrate that the site is in compliance. Within seven days of detection, the monitoring results will be placed in the Operating Record and the County will indicate actions taken and actions proposed to resolve the problem. Within 60 days of detection, the County will develop and implement a landfill gas remediation plan for the combustible gas releases and notify the Division that the plan has been implemented. The plan will describe the nature and extent of the problem and the proposed remedy. Landfill Gas Monitoring Plan Joyce Engineering, Inc. Wilkes County Dan Johnson Landfill, Permit No. 97-02 Revised July 2012 5 6.0 CERTIFICATION OF PROFESSIONAL GEOLOGIST OR ENGINEER The landfill gas monitoring plan for this facility has been prepared by a qualified geologist or engineer who is licensed to practice in the State of North Carolina. The Certification of Professional Geologist or Engineer form is included as Appendix IV. 7.0 CERTIFICATION OF REGISTERED LAND SURVEYOR All future landfill gas monitoring wells will be surveyed for location and elevation by a North Carolina Registered Land Surveyor. 8.0 REFERENCES Brown, Philip M., Chief Geologist, 1985, Geologic Map of North Carolina, The North Carolina Geologic Survey, scale 1:500,000. Joyce Engineering, Inc., October 2011. First Semiannual Groundwater Monitoring Report of 2011, Dan Johnson Landfill, Wilkes County, North Carolina. North Carolina Department of Environment and Natural Resources, 1990-2011, Solid Waste Management Regulations. North Carolina Department of Environment and Natural Resources, November 2010, Landfill Gas Monitoring Guidance. Drawings Appendix I Solid Waste Section – Landfill Gas Monitoring Guidance                                                           Appendix II Landfill Gas Monitoring Data Form Landfill Gas Monitoring Data Form Facility Name: ____________________ Permit Number: ___________________ Date of Sampling: ____________________ Personnel: ___________________ Gas Monitor Type & Serial No: ____________________ Calibration Date: ___________________ Field Calibration Date & Time: ____________________ Calibration Gas Type: ___________________ General Weather Conditions: ____________________ Barometer : ___________________ Location or LFG GW ID Instr. purged Time Well Pressure (InWg) Time Pumped (sec.) CH4 (%LEL) CH4 (%Vol) Notes Abbreviations: GW = Gas Well LEL = Lower Explosive Limit Appendix III Landfill Gas Monitoring Well Detail Landfill Gas Monitoring Well Detail Appendix IV Certification of Professional Geologist or Engineer