3603_ROSCANS_2012

AUTEN ROAD LANDFILL
PERMIT NO. 36-03

LANDFILL GAS
MONITORING PLAN
UPDATE

NOVEMBER 2012

Prepared for:

Gaston County, North Carolina
P.O. Box 1578
Gastonia, NC 28053-1578

Prepared by:

Project Number 21420
11-19-12

TABLE OF CONTENTS

SECTION PAGE

Gaston County, North Carolina November 2012
Auten Road Landfill i
1.0 INTRODUCTION .............................................................................................................. 1
1.1 Purpose ....................................................................................................... 1
1.2 Regulatory Requirements .................................................................................. 1
2.0 SITE HISTORY ................................................................................................................. 1
2.1 Background ................................................................................................... 1
2.2 Landfill Gas Monitoring .................................................................................... 2
3.0 CONTINUED LONG-TERM MONITORING PLAN ............................................................ 2
3.1 Monitoring .................................................................................................... 2
3.2 Frequency .................................................................................................... 3
3.3 Monitoring Protocols ....................................................................................... 3
3.4 Detections and Exceedences .............................................................................. 3
3.5 Notification and Reporting ................................................................................ 4
3.6 Revisions to the Plan ....................................................................................... 4

Appendix A – Site Location Map
Appendix B – Monitoring Well Location Plans
Appendix C – Groundwater/LFG Monitoring Well Typical Detail
Appendix D – LFG Monitoring Report Form
Appendix E – Well Construction As-Builts

Gaston County, North Carolina November 2012
Auten Road Landfill 1
1.0 INTRODUCTION
1.1 Purpose
This Landfill Gas Monitoring Plan (LFGMP) presents information and procedures associated with the
landfill gas monitoring program for the closed Auten Road Landfill (Permit No. 36-03). The Auten
Road Landfill is owned and maintained by the Gaston County Department of Public Works and is
located on Monterey Park Drive in Gastonia, North Carolina. A site location map of the Auten Road
Landfill is included in Appendix A – Figure 1.
1.2 Regulatory Requirements
The Auten Road Landfill did not receive waste after October 9, 1991, and is subject to compliance
with the closure requirements of 15A NCAC 13B.0510. The County has historically monitored the
site for explosive gases and groundwater contamination.
The LFGMP, as described herein, is for monitoring of methane gas concentrations at the property
boundary, and to document post-closure care actions and landfill gas (LFG) monitoring procedures
already set in-place by the County.
In accordance with 15A NCAC 13B.0503, the following requirements must be met:
 The concentration of explosive gases generated by the site shall not exceed (i) 25 percent of
the limit for the gases in site structures (excluding gas control or recovery system
components); and (ii) the lower explosive limit for the gases at the property boundary.
2.0 SITE HISTORY
2.1 Background
The Auten Road Landfill is a pre-Subtitle D (unlined) landfill that operated from 1975 until it was
closed in 1987. A chronology of key events is presented in the following table:
TABLE 1
Auten Road Landfill Key Events
Activity Date
First permitted November 1975
Landfill stops receiving waste 1987
County receives letter from State recognizing placement of 2-feet of final cover and stating
that additional grading and seeding is required for final closure certification.
April 1987
Debris from Hurricane Hugo is stored at the site as an emergency measure September 1989
Hugo debris is cleared from the site June 1990
County installs groundwater monitoring system June 1994
SWS determination that facility has been closed in accordance with applicable requirements July 1996

Gaston County, North Carolina November 2012
Auten Road Landfill 2
TABLE 1
Auten Road Landfill Key Events
Activity Date
County notification that facility will be maintained in accordance with the post closure
conditions specified in SWS letter dated July 24, 1996. County requests effective closure date
of November 28, 1995 to coincide with first groundwater monitoring event.
August 1996
SWS approves effective closure date of November 28, 1995. August 1996

The landfill is currently well vegetated and the final layer of waste is covered by a minimum of 2 feet
of soil cover in accordance with 15A NCAC 13B.0505.
The County currently performs post-closure care activities that include site maintenance, storm-water
management, erosion and sediment control, groundwater monitoring, and landfill gas monitoring.
2.2 Landfill Gas Monitoring
The County currently performs annual LFG monitoring at six permanent wells located near the
property boundary. Refer to Appendix B – Figure 3 for well locations. Based upon recent monitoring
results (from year 2006 to 2012), the recorded concentration of explosive (methane) gas is not
detected or is below the regulatory requirements noted in Section 1.2 at all monitoring locations. Per
this monitoring plan revision, the County will continue to monitor wells MW-1, TW-1, MW-3, MW-
4, and MW-5. Two shallow probes (SP-1 and SP-3) will be installed at the proposed locations noted
on Figure 3 in Appendix B. Figures 4 and 5 provide available information and details regarding the
existing permanent well construction, shallow probe construction, and head space revision for gas
monitoring. The areas southwest and east of the Auten Road Landfill are bounded by Barton Branch
Creek and Long Creek, respectively, which should restrict the possible migration of LFG across the
creek(s).
3.0 CONTINUED LONG-TERM MONITORING PLAN
3.1 Monitoring
As required by 15A NCAC 13B.503, the County is responsible for assessing and monitoring for LFG
migration, specifically off-site migration beyond the property boundary, and for determining if
methane is accumulating in any on-site structures.
There are no on-site structures located at the Auten Road Landfill, thus the Monitoring Plan for this
site consists of continued monitoring of the wells noted in Section 2.2. The County will also conduct
ambient surface monitoring of specific locations on an as-needed basis if the presence of LFG is
suspected.

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Auten Road Landfill 3
3.2 Frequency
The County will continue to monitor the permanent compliance wells on a quarterly basis throughout
the remainder of the post-closure care period. The shallow probes will be monitored quarterly for a
period of one year. Based upon the monitoring results, the County will make a recommendation to
SWS regarding continued monitoring of abandonment of the probes. The effective closure date of the
Auten Road facility was determined to be November 28, 1995 (see Table 1). If methane
concentration levels that exceed the regulatory requirements are observed, the County will institute
more frequent monitoring, following the implementation of corrective measures, until such time as it
can be demonstrated that any migration issue is resolved to the satisfaction of the County and the
Division of Waste Management.
3.3 Monitoring Protocols
Prior to initiating a LFG monitoring event, monitoring personnel (County or a third party) will record
pertinent weather information. Via the use of a LFG analyzer, the following will typically be
recorded at each monitoring well or on-site structure:
 Verification of sample tube purge;
 Time pumped in seconds;
 Barometric pressure;
 Methane concentrations (percent volume in air and lower explosive limit)
 Oxygen, carbon dioxide, and balance gas concentration; and
 Any field observations or comments.
Concentrations of gases, using a CES-Landtech, GEM 2000 analyzer (or equivalent type analyzer) at
the monitoring wells, will be determined using the following sampling procedures:
 The instrument will be calibrated per the manufacturer’s recommendations prior to use.
 The instrument will be turned on prior to sampling of the monitoring well.
 The instrument’s sampling pump will be started and readings will be observed and recorded.
Typically, two monitoring well volumes will be pumped and purged prior to recording
measurements.
 Readings will be measured for a three-five minute time interval following the well purging.
The LFG Monitoring Report form is presented in Appendix D.
3.4 Detections and Exceedences
If methane concentrations are detected above 1.25 percent by volume in on-site structures or above
5.00 percent by volume at the property boundary, the County will:
 Notify the Division of Waste Management, Solid Waste Section (SWS);
 Perform a site investigation;

Gaston County, North Carolina November 2012
Auten Road Landfill 4
 Provide SWS monitoring data related to the exceedence; and
 Propose appropriate corrective actions.
3.5 Notification and Reporting
Landfill gas monitoring under this Plan will be scheduled quarterly.
The LFG Monitoring Report form is presented in Appendix C. LFG monitoring results will be
submitted to SWS within 30 days following the completion of the monitoring event. However, if
methane concentrations from any monitoring well exceed the prescribed regulatory requirements, the
County will:
 Immediately take all necessary steps to ensure protection of human health and notify the
Division of Waste Management, SWS;
 Within seven days of detection, place the monitoring results and a description of the steps
taken to protect human health in the operating record; and
 Within 60 days of detection, implement a remediation plan and notify the SWS that the plan
has been implemented.
3.6 Revisions to the Plan
The County will implement the propose changes to the LFGMP in accordance with the following
conditions:
 Within 90 days of approval of the LFGMP by the SWS, the new gas monitoring probes will
be installed at the proposed locations as depicted on the site drawings.
 A Professional Engineer or a North Carolina Professional Geologist must certify/supervise
the installation of all LFG monitoring probes.
 Within 30 days of completion of the LFG monitoring probes, a well construction record
and/or boring log and a diagram for each probe, including but not limited to total depth,
screened interval, and distance above seasonal high groundwater elevation, 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 gas monitoring probes.

APPENDIX A
Site Location Map

Auten Road Landfill ‐ Site Location Map 

APPENDIX B
Monitoring Well Location Plans
Approximate Limits of WasterDameonMW-1
dMonterrey Park Roa
trerdM onery Pak RoaTW-1
MW-5
MW-4
MW-3
Auten Road Landfill – Monitoring Well Location Plan
Figure 2
N
SP-1
SP-3
SP-1
APPENDIX C
Groundwater/LFG Monitoring
Well Typical Detail

APPENDIX D
LFG Monitoring Report Form

Page 1 of 1
AUTEN ROAD
LANDFILL
LANDFILL GAS MONITORING REPORT – CLOSED LANDFILL

Date:

Facility Name: Auten Road Landfill

Permit Number: 36-03

Sampling Personnel:

Instrument Used:

Date Instrument Calibrated and Standard Used:

Weather Conditions:

Monitoring Well/Probe % LEL % CH4 % O2 % CO2 % Balance
Gas Comments

Facility Structures % LEL % CH4 % O2 % CO2 % Balance
Gas Comments

List wells/probes not sampled
during this monitoring event:

APPENDIX E
Well Construction As-Builts