8602_Surry_MtAiry_MSWLF_CDLF_LFGSoilVaporSurveyPlan_FID1874316_20240607

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-O8D3E2E14E92
Landfill Gas Soil Vapor Survey Plan
Surry County Closed CGD/MSW Landfill Facility
Solid Waste Permit No. 86-02
Prepared for:
Surry County Closed COD/MSW Landfill
237 Landfill Road
Mt. Airy, North Carolina
1770
June 2024
Prepared by:
— NCLIC.NO.F-1370 (ENGINEERING)
SMITH+6ARONER
14 N. Boylan Avenue, Raleigh NC 27603 1 919.828.0577
O 2024 Smith Gardner, Inc.
This document is intended for the sole use of the client for which it was prepared and
for the purpose agreed on by the client and Smith Gardner, Inc.

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
This page intentionally left blank.

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
Landfill Gas Soil Vapor Survey Plan
Surry County Landfill Facility
Solid Waste Permit No. 86-02
Prepared For:
Surry County Closed COD/MSW Landfill
Mt. Airy, North Carolina
S+G Project No. Surry-21-1
,.°'''t'► G A �?
c
6ii
SEAL
2758
DocuSignedby: tp\ C1.)�OtOG......
1:5
can G. 2��1�s--•,'�.y C. R�G�`� ``,`•
3B8305C978FA4F6._.
'����IIIFIII 1111111��+'
Seth Rickerts, P.G
Project Geologist
DocuSigned by:
,,bait Q. Swl4L
RR 11A711F4RR
Joan Smyth, P.G.
Senior Hydrogeologist
,tune 2024
�4
NCLIC.NO.F-1370 (ENGINEERING)
SMITH GARDNER
14 N. Boylan Avenue, Raleigh NC 27603 1919.828.057?

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
This page intentionally left blank.

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
Surry County Closed CGD/MSW Landfill
Mt. Airy, North Carolina
NC Solid Waste Permit No. 86-02
Landfill Gas Assessment Plan
Table of Contents
Page
1.0
INTRODUCTION......................................................................................................... 1
2.0
SITE CHARACTERISTICS............................................................................................ 1
2.1 Geology and Topography......................................................................................... 1
2.2 Hydrology................................................................................................................1
3.0
DATA EVALUATION.................................................................................................... 2
3.1 Methane Exceedances............................................................................................ 2
4.0
SOIL VAPOR SURVEY.................................................................................................. 2
5.0
ASSESSMENT REPORT..............................................................................................3
6.0
SCHEDULE................................................................................................................ 3
FIGURES
Figure 1 Proposed Soil Vapor Survey Locations
Surry County Closed CSC/MSW Landfill Landfill Gas Soil Vapor Survey Plan
May 2024 Table of Contents Page /

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
This page intentionally left blank.
Surry County Closed C6D/MSW Landfill Landfill Gas Soil Vapor Survey Plan
May 2024 Table of Contents Page //

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
1.0 INTRODUCTION
The Surry County Closed Construction and Demolition Debris over Municipal Solid Waste
(C&D over MSW) Landfill (North Carolina Solid Waste Permit No. 86-02) is located at 237
Landfill Road in Mt. Airy, North Carolina. The Surry County Closed C&D/MSW Landfill
Facility consists of a two -unit unlined MSW landfill overlain by lined C&D landfill. C&D
waste was accepted at this landfill until it's closing on June 1, 2008. The surrounding
area is currently developed as rural agricultural and residential.
Landfill gas (LFG) monitoring has been conducted at the facility on a quarterly basis. The
LFG monitoring network for the 86-02 facility consists of seven (7) LFG monitoring wells
and nine (9) onsite structures. Recent LFG monitoring events have reported elevated
concentrations of methane in LFG monitoring well MGP-7. In an email, to Surry County
from the North Carolina Department of Environmental Quality (NCDEQ), the Solid Waste
Section has requested an assessment plan to address the elevated methane readings
present in MGP-7. The plan for further assessment of these readings is outlined below.
2.0 SITE CHARACTERISTICS
2.1 Geology and Topography
The Surry County Closed C&D over MSW Landfill, located in the Piedmont -Blue
Ridge geologic province within the Inner Piedmont Belt, is underlain by the
Banded Gneiss Formation. This formation is described in the Geologic Map of
North Carolina (1985) as "Interlayered with calc-silicate rock, metaconglomerate,
amphibolite, sillimanite-mica schist, and granitic rock". Located in the western
portion of the piedmont physiographic province, elevations range from 930 feet
above mean sea level along the Stoney Creek to 1170 ft amsl at the peak of the
Landfill. The landfill property and surrounding area are shown on Figure 1.
2.2 H drolo
The groundwater monitoring network is comprised of 17 monitoring well
locations and four surface water locations (SW-1, SW-2, SW-3, SW-4), located
both up and downstream from the landfill on Stoney Creek.
Groundwater depths generally range from 10 to 60 feet with groundwater flowing
south towards the Ararat River.
Unnamed tributaries run along the eastern and western sides of the C&D over
MSW landfill. These discharge into Stoney Creek located south of this landfill unit
between the closed C&D over MSW landfill and the active MSW landfill (Permit
#86-06). Stoney Creek flows southeast before discharging into the Ararat River
near the southeastern corner of the facility.
NC DEQ Email from Jaclynne Drummond to Ricky Hawks, Jessica Montgomery. February 5,
2024.
Surry County Closed CBS/MSW Landfill Landfill Gas Soil Vapor Survey Plan
May 2024 Page 1

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
The landfill gas monitoring network and site features are shown on Figure 1.
Unfortunately, there is no available well construction information for the landfill
gas monitoring network that we could locate.
3.0 DATA EVALUATION
3.1 Methane Exceedances
Recent data indicates elevated methane concentrations are present in LFG
monitoring well MGP-7. All available LFG data is summarized in the table below:
Available Historic Methane Percentage Data
MGP-2R
MGP-3
MGP-4
MGP-5
MGP-6
MGP-7
MGP-8
1/31/2024
0
0
9.5
0
1.6
37.1
0
10/18/2023
NA
0
0.4
0
0
7.9
0
7/27/2023
NA
0
0
0
0
8.2
0
4/10/2023
NA
0
0
0
0
20.9
0
1/31/2023
NA
0
WI
0
0
35.9
0
10/3/2022
NA
0
0.7
0
0
8.6
0
7/28/2022
NA
0
16.3
0
0
11.5
0
4/4/2022
NA
0
0
0
0
0.3
0.2
1/18/2022
0
0
0
0
0
20.3
0
10/18/2021
0
0
0
0
0
16.4
0.2
3/5/2020
0
0
38.4
0
5.4
53.9
0
3/6/2020
NA
NA
2
NA
0.1
60.4
NA
Data is shown in percent CH4
NA — Data unavailable.
WI — LFG monitoring well was watered in and unable to be sampled.
It should be noted that the closed C&D over MSW landfill is surrounded on three
sides by perennial tributaries and the Ararat River as shown in Figure 1. Due to
perennial streams ability to prevent landfill gas migration it is highly unlikely
that the detected exceedances extend to the property line. Additionally, due to
the intermittent nature of exceedances in MGP-4, and it's location between the
landfill unit and the tributary investigation of this area will not be performed
unless consistent exceedances are observed.
4.0 SOILVAPOR SURVEY
S+G will perform a limited soil vapor survey in the vicinity of MGP-7, and the property
line nearest to MGP-7 to evaluate landfill gas concentrations in the area. This work
will be performed to determine if and where landfill gas is migrating to the unnamed
tributary or beyond it. Proposed soil vapor survey locations are shown on Figure 1. It
should be noted that landfill gas typically does not have the pressure to infiltrate or
Surry County Closed CBS/MSW Landfill Landfill Gas Soil Vapor Survey Plan
May 2024 Page 2

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
cross perennial water bodies such as the one downhill from MGP-7 and we do not
anticipate detecting landfill gas on the opposite site of the creek from the landfill.
The soil vapor survey will be conducted by advancing a soil vapor probe to an
approximate depth of 9 feet (or bedrock). After the probe is advanced, a landfill gas
meter will be used to measure methane concentrations in each soil vapor hole. Upon
completion of the study, each hole will be backfilled.
5.0 SOILVAPOR SURVEY REPORT
Upon completion of field activities, S+G will prepare a report that summarizes field
activities and measured results. This report will include a map depicting the final
locations of the soil vapor survey points, information on soil vapor survey depths and
conclusions from the data gathered.
6.0 SCHEDULE
The outlined soil vapor survey will be performed within 45 days of approval. A report
will be completed within 45 days of completion of field activities.
Surry County Closed CBS/MSW Landfill Landfill Gas Soil Vapor Survey Plan
May 2024 Page 3

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
This Page Intentionally Left Blank.
Surry County Closed CGD/MSW Landfill Landfill Gas Soil Vapor Survey Plan
May 2024 Page 4

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
FIGURES
Landfill Gas Soil Vapor Survey Plan
Surry County Closed COD/MSW Landfill (Permit No. 86-02)
Mt. Airy, North Carolina

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
This page intentionally left blank.

DocuSign Envelope ID: C9C7D865-CC5D-49AD-B1B2-08D3E2E14E92
LANDFILL ROAD (MAIN)
ENTRANCE (GATED)
RECYCLING BUILDING
J
A 00 0
WHITE GOODS FACILITY �n
CONVENIENCE CENTER � "� � _ \\� /° g� �l SCALE HOUSE / OFFICE
\ \ AND SCALES
\
CLOSED MSW ANDFILL
1
-4,/ l /l LCID LANDFILL (ACA7AREA
CLOSED TIRE DISPOS
USED ARE COLLECAON
AND STORAGE AREA
l / / MAINTENANCE BUILDINGS
LANDFILL ACCESS ROAD
//�/ JJ i
24 Smith Gardner, Inc.
—__i / `� /
It � CLOSED C&D LANDFILL
�SVS 4�� J� // I1� I j ` IIII IIII(\�\
�I IIII I�� � III 1\�
W LANDFILL
z
w 1WLJ
No
o
J o
W ® E
z
S
Q
o
U o
Z U
s �
CR
-
c U
� N
c
m
o
a
m�
z
CD
O
p
D
C
w
a
�
o
w
w
(-n
�
J
U
�
Q
_
N
a
z
�
�
w
D
N
o
>
0
C
N
0
S C0
LEGEND w
0
/ ✓ / l % / I//�II \\�� �� //�ji�/�i ti
PROPERTY LINE EXISTING 10' CONTOUR
EXISTING 2' CONTOUR
APPROXIMATE PROPERTY BOUNDARY c
ollo�i/i /i 1 a a N
j /�/ / j _ _ APPROXIMATE EXISTING WASTE LIMITS � o
l/iI / o / // / / / LO
\\ /MGP-6 / I1 ��\O\\\\ //� F I�/ _ ///�� r '%/ // / (UNLINED LANDFILL UNITS) Z y o
/�� SW 1 �/� / LIMIT OF LINER
// //// �%/ / / / (LINED LANDFILL UNITS) M z
MGP-3 — — — — — — C" "b
/��/ / — APPROXIMATE ACTIVITY LIMITS cn c� M
�� ��ll v ��/j ;MGP - 4 �' �/ ///// / /// %/ / I Q y77 _ a
/ / `� (I I\�� � // 1� l I \ \ 1 I (� l I REFERENCES CM � LQ
1 (I IN, 1. EXISTING SITE FEATURES AND TOPOGRAPHY FROM DRAWING J ::- -�L
— / />� \ \ I UPDATED FACILITY PLAN DATED 9/30/2020 PREPARED BY — z
MGP-5 / /% / /%/ ((% IIII / �� �l� J v MUNICIPAL ENGINEERING SERVICES COMPANY, P.A., GARNER, NC. o o
a � y
0 400' 800'