NCG120085_Corrective Actions & Testing_20230110

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Civil & Environmental Consultants, Inc.
January 9, 2023
Mr. Jerry Eplin
North Carolina Department of Environmental Quality
Division of Energy, Mineral, and Land Resources
610 E. Center Ave. Suite 301
Mooresville, NC 28115
Dear Mr. Eplin:
Subject: Union County Landfill Site Stormwater Testing and Corrective Actions
NCG 120000
CEC Project 151-797
The Union County Landfill is covered under the NCDENR General Permit NCG120000 for stormwater
point source discharge from landfilling activities. As a condition of General Permit coverage, quarterly
monitoring is required for certain constituents at the site stormwater outfalls.
The most recent site stormwater sampling event was conducted on November 30, 2022. The analytical
results for the monitored constituents were received by the landfill operator on December 5, 2022 (see
attachment). In response to the exceedance of benchmark values for analytical monitoring requirements
at several outfalls on the site, the operators of the site conducted a stormwater management inspection.
Currently, there are six separate outfalls for the site. Below is a discussion of potential causes of
benchmark value exceedance and identification of controls or other improvements for each of the five
outfalls.
Outfall 1 — The drainage area to this outfall is comprised of a portion of the north entrance asphalt drive.
This outfall discharges as overland flow to the adjacent roadside ditches of Austin Cheney Road. An
elevated level of coliforms were detected in this outfall. There was no evidence of leachate or other solid
waste material on the pavement during the inspection that might result in higher coliform levels. The site
is frequented by wildlife and it is reasonable to assume the elevated level of coliforms may be due to
animal excrement. Inspection of the entrance drive for solid waste material and or leachate will be
performed on a daily basis.
Outfall 2 — This outfall handles site drainage from the solid waste transfer station. This outfall was not
discharging during the November 30, 2022 sampling event, as a result no sample was taken. Inspection
of this area for solid waste material will continue on a daily basis.
Outfall 3 — This outfall receives drainage from the solid waste transfer station area, a portion of closed
landfill and a portion of the active Construction and Demolition (C&D) landfill. The outfall contains
Sediment Trap 1 (ST-1), Sediment Trap 2 (ST-2) and Sediment Basin 2 (SB-2). Drainage from the active
landfill area flows through SB-2, ST-1 and ST-2 before discharge. TSS and COD levels exceeded
benchmark values (106 mg/L TSS and 3,500 coliforms per 100 ml) in the November 30, 2022 sampling
event.
The drainage area to Outfall 3 is vegetated with the exception of the operating landfill and area
surrounding the transfer station. There is no standing water in ST-1, ST-2 and SB-2. The site is frequented
by wildlife and it is reasonable to assume the elevated level of coliforms may be due to
3701 Arco Corporate Drive, Suite 400 1 Charlotte, NC 28273 1 p: 980-237-0373 f: 980-237-0372 1 www.cecinc.com

Mr. Jerry Eplin — NCDEQ
CEC Project 151-797
Page 2
January 9, 2023
animal excrement. Inspection of the transfer station area for solid waste material and or leachate will be
performed on a daily basis. The drainage area will be inspected for evidence of erosion that may have
contributed to the slight exceedance in the TSS benchmark value of 100 mg/L. Areas of erosion will be
repaired within 30 days of the date of this letter.
Outfall 4 — The drainage area to this outfall contains vegetated closed landfill area. An elevated level of
coliforms were detected in this outfall. There is no evidence of landfill material or leachate as a source of
the coliforms. As in the other outfall drainage areas, the site is frequented by wildlife and the elevated
level of coliforms may be due to animal excrement.
Outfall 5 — This outfall receives drainage from the active C&D landfill. All drainage is treated in SB-1
prior to discharge to the outfall. An elevated level of coliforms were detected in this outfall. The level of
exceedance is similar to other outfalls on the site. Although inspection of wastes occur on the working
landfill daily, it is reasonable to assume the coliform exceedances originate from wildlife, similar to the
other outfalls where no landfill operations are occurring.
Outfall 6 — This outfall receives drainage from the south entrance from Austin Cheney Road. This outfall
discharges to the wooded area south of the site. An elevated level of coliforms and TSS were detected in
this outfall. There was no evidence of leachate or other solid waste material on the pavement during the
inspection that might result in higher coliform levels. Elevated coliform levels could be attributed to
wildlife activity, similar to the other site outfalls. Inspection of the entrance drive for solid waste material
and or leachate will be performed on a daily basis.
The drainage area will be inspected for evidence of erosion that may have contributed to the exceedance
in the TSS benchmark value of 100 mg/L. Areas of erosion will be repaired within 30 days of the date of
this letter.
These outfalls will continue be monitored under a Tier Three response action which requires monthly
testing (qualitative and quantitative) of the outfalls. Since the trigger of Tier Three, photographs of site
wildlife are maintained for inspection in the compliance library. Should you have any questions, please
do not hesitate to contact us at 980-237-0373.
Sincerely,
CIVIL & ENVIRONMENTAL CONSULTANTS, INC.
Donald M. Cobb, P.G. Todd Gingerich, P.E.
Project Manager Vice President
cc: Caleb Sinclair, Union County
Chris Medlin, Union County
Attachment
Civil & Environmental Consultants, Inc.

ATTACHMENT

NCDEQ Division of Energy, Mineral and Land Resources
Stormwater Discharge Monitoring Report (DMR) Form for NCG120000
Landfills
Click here for instructions
Complete, sign, scan and submit the DMR via the Stormwater NPDES Permit Data Monitoring Report (DMR) Upload form within
30 days of receiving sampling results. Mail the original, signed hard copy of the DMR to the appropriate DEMLR Regional Office.
Certificate of Coverage No. NCG12
Person Collecting Samples:
Facility Name: _
Laboratory Name: p �,
Facility County: n%Cn
Laboratory Cert. No.: 42—
Discharge during this period:
FTYes
Q No (if no, skip to signature and date)
Has your facility implemented mandatory Tier response actions this sample period for any benchmark exceedances? []3 es ® No
If so, which Tier (I, II, or III)? � i 1
A copy of this DMR has been uploaded electronically via https://edocs.deg.nc.gov/Forms/SW-DMR ®"Yes No
Date Uploaded:
Analytical Monitoring Requirements for Outfalls with Industrial Activities — Benchmarks in (Red)
Parameter
Code
Parameter
Outfall
Outfall
Outfall
Outfall
Outfall
N/A
Receiving Stream Class
0
3
m
N/A
Date Sample Collected MM/DD/YYYY
7.�77C.
ii �, .i, -
�� _
�� •, Z,Z�,
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46529
24-Hour Rainfall in inches
Il, ,,;
l
vS
l .
C0530
TSS in mg/L (100 or 50*)
��.
`, 3
�\
Z 0 3
00400
pH in standard units (6.0-9.0 FW,
6.8 — 8.5 SW)
00340
Chemical Oxygen Demand in mg/L
yy�� e[�.
/
(120)
\V�V
��s. 4:
p
S C.
`► i
� �latY
(, j t
C '1 .43
31616
Fecal Coliform in # per 100 ml (1000)
Additional parameters for outfalls in drainage areas that use >55 gallons per month of new hydraulic oil on average
00S52
Non -Polar Oil & Grease in mg/L (15)
Estimated New Motor/Hydraulic Oil
NCOIL
Usage in gal/month
Outfalls to Outstanding Resource Waters (ORW), High Quality Waters (HQW), Trout Waters (Tr) and Primary Nursery Areas (PNA)
have a benchmark TSS limit of 50 mg/L. All other water classifications have a benchmark of 100 mg/L.
FW (Freshwater) SW (Saltwater)
Notes (optional):
"I certify by my signature below, 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 fines and imprisonment for knowing violations."
Signature of Permittee or Delegated Authorized Individual
Email Address