7407_Pitt_CandDLandfillInc_20191030_MNARequest_FID1360816

wood.
October 30, 2019
Ms. Jaclynne Drummond
Hydrogeologist, Solid Waste Section
Division of Waste Management
North Carolina Department of Environmental Quality
2090 U.S. 70 Highway Swannanoa
Asheville, NC 27887-8211
RE: MNA SAMPLING FREQUENCY MODIFICATION REQUEST
C&D LANDFILL
PITT COUNTY, NORTH CAROLINA
PERMITS 7407-CDLF-2001-2009
Dear Ms. Drummond:
On behalf of C&D Landfill, Inc., Wood Environment & Infrastructure Solutions Inc. (Wood) is requesting
modifications to the Monitored Natural Attenuation (MNA) sampling schedule at the C&D Landfill located
at 802 Recycling Lane, Greenville, North Carolina (Site). The Site is an active construction and demolition
debris landfill permitted by the North Carolina Department of Environmental Quality (NCDEQ), Division of
Waste Management (DWM), Solid Waste Section (SWS) under Permits 7407-CDLF-2001 and 7407-CDLF-
2009. As we discussed during our phone call on October 9, 2019, baseline monitoring of MNA parameters
is complete and reducing the monitoring frequency of some MNA parameters is appropriate. The site
background and proposed changes to the monitoring schedule presented are below.
Site Background
The Site currently consists of two phases (Figure 1). Both phases are in the assessment stage of the
Assessment and Corrective Action Program for C&DLF Facilities and Units, and C&D Landfill, Inc. is in the
process of preparing a corrective action permit modification application for the Site. Water quality
monitoring at the Site is conducted semi-annually in May and November. C&D Landfill, Inc began
collecting groundwater samples for the full list of MNA parameters in December 2017 and the fourth and
final baseline MNA samples were collected in Spring 2019.
The groundwater monitoring network consists of 12 wells within Phase 1 and 10 wells within Phase 2.
Within Phase 1 there is one upgradient, background well (MW-1S), eight downgradient compliance wells
(MW-2S, MW-3S, MW-4, MW-5, MW-6, MW-7, MW-3A, and MW-8), and three deeper wells (MW-1D,
MW-2D, and MW-3D). Within Phase 2 there are three upgradient wells (MW-9A [background], MW-16,
and MW-17), six down gradient compliance (MW-10, MW-11, MW-12S, MW-13, MW-14S, and MW-15),
and one deeper well (MW-14D).
Proposed Monitoring Changes
MNA is expected to be utilized as a groundwater remedy at the Site and continuing to monitor certain
MNA parameters semi-annually will aid in understanding the potential for degradation of contaminants
and assessing whether degradation is occurring. Other parameters are less relevant to Site conditions and

C&D Landfill, Inc
MNA Sampling Frequency Modification wood.
can be monitored on a three-year basis. The following MNA parameter monitoring frequencies are
proposed for each well in Phases 1 and 2.
The field parameters collected to monitor groundwater stabilization during low -flow sampling will
continue to be collected during each semi-annual monitoring event. These parameters include:
• Temperature,
• Turbidity,
• Dissolved oxygen (DO),
• Conductivity, and
• Oxidation/Reduction Potential (ORP).
Of these field parameters, DO and ORP are particularly useful for monitoring the aerobic state and the
oxidizing/reducing conditions within an aquifer. In addition to the field parameters, semi-annual
groundwater samples will continue to undergo laboratory analyses the following MNA parameters:
• Sulfate,
• Sulfide (an Appendix II constituent),
• Nitrate, and
• Alkalinity.
Sulfate and Sulfide concentrations will be used together to assess the oxidative/reductive condition of the
aquifer, and nitrate and alkalinity will be used to assess biological activity. The remaining MNA parameters
specified for monitoring by the SWS will be monitored every three years for comparison to the baseline
concentrations, or as needed based on potential future remedies. The parameters selected for reduced
three-year monitoring include:
• Carbon Dioxide • Total Organic Carbon • Biological Oxygen Demand
• Ethane • Chemical Oxygen Demand • Total Dissolved Residue
• Ethane • Hardness • Volatile Fatty Acids
• Methane • Hydrogen • Ferrous Iron
• Chloride
Note that methane will continue to be monitored in landfill gas samples. New landfill gas monitoring points
are scheduled for installation before the end of 2019.

C&D Land fill, Inc
MNA Sampling Frequency Modification
Closing
wood.
If you have any questions concerning this the proposed changes to the MNA monitoring schedule, please
contact Sheri Knox at [phone] or Damian Hriciga at [phone].
Respectfully,
Wood Environment & Infrastructure Solutions, Inc.
Damian Hriciga, PG Sheri L. Knox, PE
Senior Geologist Associate Remediation Engineer
Attached: Figure 1 Monitoring Well and Surface Water Sampling Location Map
cc: Wayne Bell, C&D Landfill, Inc.

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C&D Landfill 9
802 RECYCLING LANE
GREENVILLE, NC 27834 MONITORING WELL AND
SURFACE WATER SAMPLING LOCATION MAP
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SCALE: 1 " = 200 ' DATE: 05/01 /2019 PROJECT: 6480199035
Wood Environment & Infrastructure Solutions, Inc.
4021 Stirrup Creek Drive, Suite 100 DRAWN BY: D. Hriciga CHECKED BY: S. Knox
Durham, NC 27703
[phone] LOCATION: 56548 142Prt RTig\NC\NC DENR DSCA\DSCA Projects\DC640004 - CleanCleanDrycleaners\
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