9701_ApprovedGasMonitoringPlan_20120711

2211 W. Meadowview Rd
Suite 101
Greensboro, NC 27407

tel: [phone] fax: [phone]
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: Germantown Landfill (#97-01)
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.

Revise the Germantown Landfill Gas Monitoring Plan, Page 2, table for “Proposed Monitoring
Well Summary” by adding GW-4 and well construction criteria to the list.
 GW-4 information has been added to Table 2

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

GERMANTOWN LANDFILL
PERMIT NO. 97-01

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: [phone]
FAX: [phone]
JOYCE PROJECT NO. 356.1102.12, TASK NO. 01
Landfill Gas Monitoring Plan Joyce Engineering, Inc.
Wilkes County Germantown Landfill, Permit No. 97-01 Revised July 2012
i

LANDFILL GAS MONITORING PLAN
Germantown Landfill
Permit No. 97-01

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 ................................................................................2
2.1 Landfill Gas Monitoring Network .................................................................................2
2.2 Structure and Ambient Sampling .................................................................................3
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 .................................................................................4
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 ................................................................................................5
6.0 CERTIFICATION OF PROFESSIONAL GEOLOGIST OR ENGINEER .............5
7.0 CERTIFICATION OF REGISTERED LAND SURVEYOR ....................................5
8.0 REFERENCES ................................................................................................................6

Drawings
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 Germantown Landfill, Permit No. 97-01 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 drawings.

1.1 Background

The Germantown Landfill is a closed, unlined municipal solid waste (MSW) landfill owned by
Wilkes County. The landfill ceased daily operations in 1993. The landfill property is located near
the town of Wilkesboro, North Carolina. The closed landfill currently houses the Wilkes County
Fire Marshal and training grounds. The area surrounding the landfill is primarily residential,
agricultural and contains open fields and woodlands.

Closure of the landfill included installation of 10 passive gas vents. In 2005, 4 of the vents were
connected with Landtec wellheads to a 6” diameter below-ground HDPE pipe system designed
to collect the landfill gas. A condenstate trap was installed toward the base of the landfill to
capture condensate. Several years later, the HDPE pipe was further extended along the edge of
the access road and a second condensate trap was installed. In 2009, an above-ground section of
6” diameter HDPE pipe was added. In 2011, the Germantown Landfill received approval from
NCDENR to construct and operate a landfill gas beneficial use project. The project is currently
being constructed.

1.2 Site Geology and Hydrogeology

The Germantown Landfill is located at the boundary of the Inner Piedmont Belt and Blue Ridge
Belt in the Brevard Fault Zone. In the vicinity of the site, the Brevard Zone is a five-mile wide,
east-northeast trending fault zone with a complex structural and metamorphic history. Finely
interlayered gneiss and schist within the zone are amphibolite facies, with peak metamorphism as
high as the kyanite zone for pelitic assemblages.

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
Landfill Gas Monitoring Plan Joyce Engineering, Inc.
Wilkes County Germantown Landfill, Permit No. 97-01 Revised July 2012
2

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 Germantown Landfill will be performed throughout the post-closure care
period. At a minimum, quarterly monitoring will be conducted at all subsurface gas detection
wells and in all structures located on the landfill property. This site is one of three Wilkes County
landfill sites that Joyce Engineering monitors. Dan Johnson 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 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 4 wells (GW-1, GW-2, GW-3 and GW-4) 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 and GW-2 are proposed to be near the
northern portion of the site on either side of the entrance road, GW-2 is proposed to be adjacent
to the pole barn and GW-4 is proposed to be place west of the office building. Note that the
Germantown Landfill is bordered by Moravian Creek to the east. The creek acts as a hydraulic
barrier to the movement of subsurface landfill gas. To the south of the landfill the terrain tends to
decline into a valley. Since landfill gas has a tendency to be lighter than air, it is not believed that
the landfill gas will sink in this area. Therefore, no landfill gas monitoring wells have been
proposed for the east or south 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 50 5-50 50 Soil/Saprolite
*GW-2 Proposed 50 5-50 50 Soil/Saprolite
*GW-3 Proposed 50 5-50 50 Soil/Saprolite
*GW-4 Proposed 50 5-50 50 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.
Landfill Gas Monitoring Plan Joyce Engineering, Inc.
Wilkes County Germantown Landfill, Permit No. 97-01 Revised July 2012
3

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 currently three structures monitored for explosive gases. The structures include the
facility’s maintenance garage, office building, and a barn. The monitored structures are identified
on Drawing No. 1.

2.3 Landfill Gas Monitoring Frequency

The landfill gas wells and on-site structures 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.

Landfill Gas Monitoring Plan Joyce Engineering, Inc.
Wilkes County Germantown Landfill, Permit No. 97-01 Revised July 2012
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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.

Gas monitoring in on-site structures will attempt to identify the "worst case" concentrations. The
monitoring locations will be in corners along floors and ceilings, at cracks in the floor, and at
other areas likely to accumulate gas. Gas monitoring will also be conducted in any confined
space requiring the entry of personnel for maintenance or inspection. The monitoring will take
place prior to entry by personnel in accordance with OSHA regulations.

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 form is included as Appendix II.

4.2 Sampling Reports

The landfill gas monitoring report will be prepared in accordance with (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 the facility or an alternative location
near the facility approved by the Division.

Landfill Gas Monitoring Plan Joyce Engineering, Inc.
Wilkes County Germantown Landfill, Permit No. 97-01 Revised July 2012
5

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.

If the compliance level is exceeded in an on-site structure, options will be evaluated to reduce the
current methane levels and to prevent further migration of methane into the structure. At a
minimum, the following actions will be taken if the methane concentration exceeds 25% in any
structure:

 Put out all smoking materials and turn off all ignition sources;
 Evacuate all personnel;
 Vent the structure;
 Do not allow personnel to reenter the building except to perform gas monitoring until the
results of additional monitoring indicate that methane concentrations are sustained or
stabilized below 25% LEL;
 Begin continuous monitoring within the structure; and
 Undertake an assessment to determine the origin and pathways of the gas migration.

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.

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.
Landfill Gas Monitoring Plan Joyce Engineering, Inc.
Wilkes County Germantown Landfill, Permit No. 97-01 Revised July 2012
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8.0 REFERENCES

Brown, Philip M., Chief Geologist, 1985, Geologic Map of North Carolina, The North Carolina
Geologic Survey, scale 1:500,000.

Fetter, C.W., 2001, Applied Hydrogeology, Fourth Edition: Prentice-Hall, Inc..

Johnson, A.I., 1967, Specific Yield - Compilation of Specific Yields For Various Materials: U.S.
Geological Survey Water Supply Paper 1662-D.

Joyce Engineering, Inc., June 2012. First Semiannual Groundwater Monitoring Report of 2012
Germantown 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