9201_Wake_CityofRaleigh_WildersGrove_MSWLF_ConstructionReportLFGExtraction_FID1811326_20230724

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Construction Completion Report
— Landfill Gas Extraction
System Modifications
City of Raleigh
Wilders Grove Landfill
Project Number: 60620631
July 20, 2023
City of Raleigh Solid Waste
Services

AECOM Environment
Quality Information
Prepared by
i
--
Gerardo Barrera Giron
Staff Engineer
Reviewed by
Jasen inna, P
Senior roject igineer
City of Raleigh
Wilders Grove Landfill
Prepared for:
Mr. Stan Joseph
City of Raleigh Solid Waste Services
630 Beacon Lake Drive
Raleigh, NC 27602-0590
Prepared by:
Reviewed by
Jon Kucera, PE
Project Manager/Engineer
AECOM Technical Services of North Carolina, Inc.
5438 Wade Park Blvd, Suite 200
Raleigh, NC 27607
Tel: [phone]
60620631 July 20, 2023

AECOM Environment ii
Table of Contents
1.0
Introduction................................................................................................................................
2
1.1 Historic Boundary Probe Assessments/Monitoring..................................................................
2
1.2 Limitations................................................................................................................................2
1.3 Registered Processional Statement.........................................................................................
3
2.0
Landfill Gas Extraction System Modifications...................................................................................
4
2.1 Central and Southeastern Well Modifications..........................................................................
4
2.2 Western LFG Header and Extraction Wells.............................................................................
4
2.3 LFG Valves..............................................................................................................................
5
2.4 Northeastern Horizontal Extraction Well..................................................................................
6
2.5 LFG Condensate Collection Sumps.........................................................................................
6
2.6 Surveying, Grading, and Seeding............................................................................................
8
3.0
Scope Additions................................................................................................................................
9
3.1 Southcentral Horizontal Extraction Well...................................................................................
9
3.2 Culvert LFG Header Repair.....................................................................................................
9
3.3 Grand Junction Discharge Line/Force Main...........................................................................
10
4.0
Conclusions...............................................................................................................13
5.0
Recommendations.........................................................................................................................
14
6.0
References...............................................................................................................15
FIGURES
Figure 1 Pre -Expansion Site Plan
Figure 2 As -Built LFG Extraction System Modifications Site Plan
Figure 3 Shallow Backfill and Collector Trench Low -Point Locations
APPENDICES
Appendix A Boundary Probe Methane Levels
Appendix B Landfill Gas Extraction System Modifications As -Built Package
Appendix C As -Built Photo Log
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AECOM
Environment
List of Acronyms
CF
Cubic foot
CS
Condensate sump
EW
Extraction well
GJ
Grand junction
GPM
Gallons per minute
Ft bgs
Feet below ground surface
HDPE
High -density polyethylene
HW
Horizontal well
LEL
Lower explosion limit
LFG
Landfill gas
OW
Original well
SUM
Standard cubic feet per minute
60620631 July 20, 2023

AECOM
Environment
1.0 Introduction
This report has been prepared for submittal to the City of Raleigh Solid Waste Services. The report
provides a summary of construction activities performed for the expansion of the existing landfill gas
(LFG) extraction system following the recommendations included in the Wilders Grove Perimeter
Methane Memo, submitted July 1 st, 2020, for the City of Raleigh's Wilders Grove Solid Waste Landfill
(the Site).
The Site is a municipal solid waste landfill located at 630 Beacon Lake Drive in Raleigh, North
Carolina. The facility received municipal solid waste from Wake County and parts of Johnston County
through its closure in 1997, and currently operates under Small/Synthetic Minor Air Operating Permit
No. 08835R05.
The Site is located on a 259-acre facility, with an approximate disposal area of 120 acres, separated
into three different units. All disposal units are unlined, with no leachate collection system. A site plan
of the existing system is included as Figure 1. An active landfill gas (LFG) extraction system was
originally installed in 1987 and has been expanded/modified since. The associated LFG collection
and treatment system consisting of approximately 77 extraction wells (EW), pneumatic pumps (which
remove condensate/water from the sumps), associated buried and aboveground collector and header
piping, and a blower that conveys the LFG to an onsite open flare. Additionally, approximately 21 of
the gas extraction wells recover condensate/water, which is discharged from the Site via the sanitary
sewer on the Northern corner of the site.
1.1 Historic Boundary Probe Assessments/Monitoring
September 2016, City of Raleigh personnel provided AECOM with perimeter methane monitoring
data which demonstrated that methane levels in some boundary probes exceeded the lower explosive
limit (LEL), as illustrated in Appendix A. In October and November 2016, AECOM extracted methane
gas from multiple boundary probes to evaluate whether the methane levels detected were "trapped"
methane or were from active migration. Results indicated that the methane levels detected were likely
resulting from active migration as the levels did not decrease after hours of extraction. Thus, in
December 2016, AECOM recommended the installation of additional methane monitoring boundary
probes to further assess the area of elevated methane levels as part of a pilot test to evaluate
expansion of the methane extraction system.
Eight new boundary probes and one replacement boundary probe were installed in August 2018 to
further delineate methane concentrations along the limits of waste. Additionally, a new extraction well
(EW), EW-54, was installed in the western area of the landfill to utilize in a pilot test. This work was
performed to aid in the design of an expansion of the LFG extraction system. Upon completion of
methane monitoring at the new boundary probes and short-term extraction at EW-54, it was
recommended to the City that installation of additional LFG extraction wells, at the western and
northeastern boundaries of the Site, could prevent elevated methane levels from appearing outside
the property boundary (AECOM, 2020).
1.2 Limitations
Historical site information presented in this report was obtained primarily from review and
interpretation of available historical reports and drawings. AECOM does not assume or accept any
responsibility or liability for the quality, accuracy, or completeness of prior piping and infrastructure
included in this report that was not installed by, or on behalf of, AECOM.
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AECOM Environment
1.3 Registered Professional Statement
I, Jasen Zinna, a Professional Engineer for AECOM, do certify that the information contained in this
report is correct and accurate to the best of my knowledge.
Jasen Zinna, P.E.
License # 040228
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60620631 July 20, 2023

AECOM
Environment
2.0 Landfill Gas Extraction System Modifications
Field activities for the LFG extraction system modification were completed between November 2022
to February 2023 by a subcontractor (Advance One) hired by the City of Raleigh. These field activities
were executed under the supervision of an AECOM representative to verify the work was completed
per the bid specifications and to approve any modifications. Since there was limited construction
documentation of the existing LFG extraction system, field modifications had to be completed for a
fully functional system. A revised LFG extraction system layout following the expansion/modifications
is illustrated in Figure 2 and a complete as -built package can be found in Appendix B. Details of the
field activities performed are provided in the sections below.
2.1 Central and Southeastern Well Modifications
The central (EW-26, EW-36, EW40, W-41A, EW-42, EW-47, and EW-48A) and southeastern (OW-
01, OW-03, and OW-05) wells were originally located downgradient in elevation from the vacuum
header line, which allowed condensate (generated from LFG extraction operations) to accumulate at
the lateral connection of each well which limited or blocked LFG extraction. The central wells were
modified to re-route laterals to nearby vacuum connections at extraction wells lower in elevation,
minimizing condensate accumulation at the lateral connections. A new LFG header was installed for
the southeastern wells, lower in elevation, to eliminate water blockages at the lateral connections,
allowing condensate to flow down the new LFG header and feed into a nearby condensate sump.
Central and southeastern extraction well modification locations are outlined in Appendix B — Sheet
2.
Trenching activities commenced on November 29, 2022, for a 500-foot (ft) LFG header downgradient
of southeastern wells (OW-01, OW-03, and OW-05). The LFG header trench was completed at a
depth of 30-inches below ground surface (bgs); trench detail shown in Appendix B — Sheet 6. A 6-
inch DR-17 HDPE pipe was installed throughout the length of the trench, accompanied by 4-inch DR-
17 HDPE laterals extending to OW-01, OW-03, and OW-05. Following the southeastern well
modifications, the central wells were re-routed to vacuum connections from nearby wells. A new
vacuum line was installed between EW-26 and CS-25 to prevent EW-26 from being watered in. Wells
EW-40, W-41A, and EW-42 were connected in sequence to W-28Awith 4-inch DR-17 HDPE laterals.
Remaining wells (EW-36, EW-47, and EW-48A) were re-routed with DR-17 HDPE laterals towards
the lateral for EW-37.
All LFG headers and lateral connections were installed with a 3% slope (Appendix B — Sheet 6) to
direct the flow of condensate towards nearby sumps. Orange geotextile (8oz) and copper tracer wire
(12-AWG) were placed over the HDPE header and laterals to locate the underground pipe. Once the
LFG header and lateral piping were fused and pressured tested at 10 pounds per square inch (PSI),
the trench was backfilled with approximately 2-ft of native soil and compacted in 6-inch lifts. All
abandoned piping from the existing system was removed or capped with a DR-17 fusion weld.
2.2 Western LFG Header and Extraction Wells
A new LFG header, four additional extraction wells, and two condensate sumps were installed along
the western edge of the landfill. Modifications to the lateral piping at seven existing EWs (EW-15
through EW-20 and EW-54) were included in this scope to prevent the extractions wells from being
watered in. Re-routing these wells to the new LFG header would increase reliability of LFG extraction
by directing condensate away from the wellheads and minimize maintenance visits over time.
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AECOM Environment
Advance One began work on the LFG header (approximately 2,400 ft) installation at the southwestern
boundary of the Site on November 29, 2023. Advance One uncovered the existing 12-inch HDPE
LFG header downgradient of EW-22, at a depth of 3 to 4-ft bgs. Advance One cut the 12-inch LFG
header and installed "T" connection and a 10-inch gear operated butterfly valve (Type 57) to serve as
an isolation point for the new LFG header.
Trenching for the western LFG header continued northwest at a depth between 12 to 30-inches bgs
(depending on how deep trash was encountered), following the landfill waste limits until EW-15 was
reached (Appendix B — Sheet 2). The trench route passed through a topographic high -points near
EW-21 and EW-17, where the trench maintained a 3% slope on either side of the highpoint to provide
adequate fall, directing condensate to nearby condensate collection sumps (CS-16, CS-54, and CS-
GJ). The western LFG header varied in diameter (10-inch, 8-inch, and 6-inch DR-17 HDPE pipe) and
was reduced in size the further the wells were from the blower as airflow was reduced (e.g., fewer
extraction wells connected to header). The header line was pressure tested at 10 PSI to verify proper
seals at the fused pipe locations. Further details of condensate collection sumps on the western LFG
header are discussed in Section 2.5.
Four new methane gas extraction wells (EW-55, EW-56, EW-57, and EW-58) were installed by
Geologic Exploration (GEX), a North Carolina licensed driller, on December 12, 2022. The EWs were
drilled utilizing hollow stem augers, a borehole diameter of 10-inches, and a total depth of 25-ft bgs.
The well screens (20 ft long) are comprised of perforated (0.02-inch perforations) 4-inch schedule 80
PVC and the filter pack is #9 Washed Granite as shown in Appendix B — Sheet 5, until reaching the
landfill liner depth (approximately 4.5-ft bgs). Geomembrane patches and wellbore seal pipe boots
were installed near the landfill liner depth of the EWs to help prevent gas leaks and air intrusion. The
remainder of the borehole was completed with fine sand, cement grout, and native soil. QED Quick -
Change wellheads were installed at new EWs for flow control and to collect compliance readings.
Final installations are presented in the photo log in Appendix C.
Lateral pipe connections for the new EWs (EW-55, EW-56, EW-57, and EW-58) and existing EWs
(EW-15, EW-16, EW-17, EW-18, EW-19, EW-20, and EW-54) were trenched and 4-inch DR17 HDPE
was installed at a 3% slope down to the new LFG header. All previously utilized lateral pipe
connections for the existing EWs were cut below grade and capped.
Orange geotextile (8oz) and copper tracer wire (12-AWG) were placed over all HDPE piping (LFG
header and laterals) to locate the underground pipe. The western LFG header trench was backfilled
with approximately 2-ft of native soil and compact in 6-inch lifts. There are a few locations that do not
have 2-ft of native backfill cover (outlined on Figure 3) because trash was encountered closer to the
surface.
2.3 LFG Valves
AECOM recommended to find the three underground LFG valves that run alongside the western LFG
header loop; two valves are located beside EW-33A and one is located upgradient of EW-15. Closing
the valve between EW-32 and EW-33A and the valve upgradient of EW-15 would prevent condensate
from infiltrating abandoned piping and leaving the other valve open would allow condensate from the
LFG header loop to drain into condensate sump CS-16.
On January 5, 2023, Advance One searched for buried valves on either side of EW-33A and upgradient
of EW-15. The construction team found the two valves located beside EW-33A, each located 3-4 ft bgs,
and verified positioning (found in Appendix B — Sheet 2); however, Advance One was not able to locate
the valve upgradient of EW-15. On February 23, 2023, Advance One and AECOM agreed to trace the
HDPE lateral piping, previously connected to EW-15, up the hill from the presumed valve location.
60620631 July 20, 2023

AECOM Environment
Excavation of the 4-inch HDPE pipe continued horizontally into the hill until Advance One reached a
depth greater than 6-ft. The HDPE pipe was then cut, capped, and buried in place.
2.4 Northeastern Horizontal Extraction Well
Landfill gas has been routinely detected above the LEL in the northeastern boundary probes which
indicates that the nearby EWs do not have enough influence to prevent LFG from migrating off the
landfill property boundary. A horizontal LFG collector trench was proposed as a necessary
engineering control to extract landfill gas beneath the surface and help prevent LEL detections at the
site boundary.
On January 6, 2023, Advance One began installing the perforated horizontal well (HW) near OW-25
and followed the base of the landfill towards OW-19 (approximately 2,200-ft). The HW is constructed
with 2-inch DR11 HDPE pipe with holes drilled in the bottom of it every 3-inches and was installed at
a depth between 2.5 to 5.5-ft due to encountering trash. The bottom of the trench was backfilled with
pea gravel (#4 stone) and 12 to 30-inches of topsoil covers over the stone backfill. Details of the HW
can be found in Appendix B — Sheet 6.
The design depth of 6.5 ft was not possible in this section of the site as trash was encountered closer
to the ground surface and the pipe needed to be set above the trash. Locations that contain less than
30-inches of topsoil cover in the northeastern horizontal LFG collector trench (northeastern HW) are
outlined in brown on Figure 3. The least amount of cover was observed between HW-103 through
HW-105 at approximately 12-inches of topsoil over the stone backfill. Multiple rainstorm events
occurred during trenching operations and as a result, stormwater pooled at certain locations (outlined
in Figure 3). In locations where standing water was observed in the trench, Advance One added
additional stone backfill underneath the HW to help prevent the pipe from being submerged. Advance
One installed one 8-inch HPDE pump -out point near HW-101 at a depth of 5-ft, surrounded with 2.5
ft of gravel at the base to facilitate water accumulation for removal. Trenching of the HW was
completed on January 16, 2023, including placement of orange geotextile (8 oz) and copper tracer
wire (12-AWG) over all HDPE piping (LFG header and laterals) to help locate the non-metallic piping.
The HW was backfilled with approximately 2.5-ft of native soil and compacted in 6-inch lifts.
Seven QED Quick -Change wellheads (HW-101 through HW-107) were installed along the HW to
provide monitoring access and airflow control. The wellheads were connected to the HW utilizing 4-
inch HDPE pipe at a 3% slope (Appendix B — Sheet 6) towards the LFG collector trench for
condensate drainage. Wellheads HW-101 through HW-105 were connected directly to the 6-inch LFG
header that runs parallel to the horizontal LFG collector trench and wellheads HW-106 and HW-107,
along with OW-24 and OW-25, were routed to the 4-inch LFG header near OW-25. (Appendix B —
Sheet 2).
2.5 LFG Condensate Collection Sumps
Condensate collection sumps are essential to maintaining the LFG extraction system in operation by
minimizing the likelihood of blockages from water accumulation in the LFG headers. Installation of
four condensate collection sumps (CS-16, CS-19, CS-25N, and CS-54) began on January 16, 2023,
and was completed on January 20, 2023. Each condensate sump is 17-ft in length (from the base to
the top of the flange cover) and required excavation below the landfill trash layer to a depth of
approximately 17-ft bgs. Prior to positioning the condensate collection sump body, 1-ft of gravel was
placed to provide a stable base. Once lowered into place and positioned, both the excavated soil and
trash were compacted into the sides of the condensate sump to maintain position. Geomembrane
patches and pipe boots were installed near the landfill liner depth of CS-16 and CS-54 to prevent gas
leaks and repair any landfill liner damaged during excavation. The locations of CS-19 and CS-25N
did not have a landfill liner and were installed without the geomembrane patch and pipe boot. All
60620631 July 20, 2023

AECOM Environment
remaining landfill trash not utilized to install the condensate sumps was placed in roll -offs by Advance
One and picked -up for off -site disposal.
Collection sumps CS-16 and CS-54 were installed to collect condensate from the new EW along the
new western LFG header discussed in Section 2.2. These sumps were placed at low points of the
new LFG header, allowing any condensate generated from LFG operations to flow down to the
collection sumps and be pumped out to the discharge location.
Condensate sumps CS-19 and CS-25N were installed in areas where existing LFG headers and/or
EWs would frequently get blocked by condensate. Extraction well OW-19 would often get watered -in
and become inoperable due to its downgradient position from the LFG header so CS-19 was installed
nearby at a lower elevation. Extraction wells on the northern section of the Site (EW-07, EW-08, etc.)
would also get watered -in due to a low spot in the LFG header. Thus, CS-25N was installed near the
low -point of elevation, enabling condensate to flow down into the sump and allow vacuum to reach
the northern extraction wells.
As illustrated in Appendix B — Sheet 4, each condensate sump is equipped with a pneumatic QED
AP4+ Ultra pump which provides pumping rates up to 13 gallons per minute (GPM) for minimal solids
buildup, as well as stainless steel parts (316-grade) for greater corrosion resistance. The pumps were
connected to a 2-inch airline (DR9 HDPE) to power the pumps and a 2-inch force main line (DR11
HDPE) to discharge the condensate.
New airlines and force main lines (utilities) were installed and connected to nearby EWs to operate
the pumps. The lines were run from the following EWs:
• EW-01 provides utilities to CS-25N
• EW-17 provides utilities to CS-16
• EW-19w provides utilities to CS-54
• OW-22 provides utilities to CS-19
On February 23, 2023, during final installation of the four condensate sumps, Advance One noted
backpressure on the discharge lines to CS-16, CS-25N, and CS-54. Backpressure on the discharge
line could indicate crossed lines (between air and discharge), physical blockage(s) in the discharge
pipe, or airlock(s) along the discharge line.
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AECOM Environment
2.6 Surveying, Grading, and Seeding
Advance One performed all surveying activities throughout installation of all piping components.
Survey data includes coordinates, depth, size, and connections for all piping installed. AECOM
utilized this information to deliver the as -built package in Appendix B.
Advance One was responsible for performing all grading wherever earth -moving activities and
disturbances occurred. The grading was completed directly after each phase of work. Minimal grading
occurred in some sections of the northeastern HW collector due to wet soil conditions that limited the
use of heavy machinery.
Advance One performed a combination of hydroseeding and hand-seeding/straw for rehabilitation of
vegetation in the disturbed areas. Wells OW-1 through OW-5 and parts of the western LFG header
received hydroseed, while sections between CS-54 through EW-15 received hand -seeding and straw
to prevent wind from displacing the seeds. All other sections were rehabilitated by hand -seeding and
straw.
On February 24, 2023, Advance One completed all final grading and seeding for all disturbed areas
relating to the scope of work.
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AECOM
Environment
3.0 Scope Additions
3.1 Southcentral Horizontal Extraction Well
Elevated methane readings had been detected at the surface in an area south of EW-26 near the
edge of waste. Thus, a horizontal EW was added to collect any LFG in the area and prevent surface
emissions.
Trenching for the perforated HW collector occurred on January 18, 2023, and extended approximately
200-ft in length at a depth of 6.5-ft. The trench contains approximately 4-ft of pea gravel backfill, a 2-
inch (DR11 HDPE) perforated HW, and 30-inches of topsoil cover over the stone backfill. Details of
the HW can be found in Appendix B — Sheet 6. The HW is furnished with a QED Quick -Change
wellhead (HW-108) and is connected to the 12-inch LFG header passing directly below the trench.
Advance One installed one 8-inch HPDE pump -out point at the base (low spot) of the trench at a
depth of 6 ft. The pump -out point was backfilled with 3-ft of gravel at the base to allow water
accumulation for removal. The horizontal EW was completed with geotextile and copper wiring and
backfilled/compacted on January 20, 2023.
3.2 Culvert LFG Header Repair
A new culvert was installed as part of a stream restoration project in the area between the old landfill
unit (e.g., OW-1 through OW-7) and the new landfill unit (e.g., EW-26 and OW-8A). The new culvert
was installed for the road that crosses the stream near HW-108 and required removal of the previous
8-inch LFG header that ran through the area. Once the new culvert was completed, it was noted that
the culvert was higher in elevation and a section of the header would have to be elevated.
On January 23, 2023, repairs began for the removed section of the LFG header near the stream.
Advance One excavated the LFG header on each side of the stream far back enough to make new
connections. During excavation activities, a 3-inch connection was discovered at a low -point of the
existing LFG header which was presumed to be for condensate collection. Advance One installed a
new section of pipe (8-inch DR17 HDPE) across the culvert that was sloped toward the 3-inch
condensate collection location. Due to the elevation of the new culvert, only a 1 % slope was achieved
towards the collection location. The LFG header was completed with geotextile and copper wiring
and backfilled/compacted on January 27, 2023.
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AECOM Environment 10
3.3 Grand Junction Discharge Line/Force Main
Personnel had been noticing backpressure on the discharge line for the grand junction condensate
sump (CS-GJ) which limits discharge and allows condensate to fill up at the primary sump. When
condensate accumulates at CS-GJ and fills the sump up, the LFG extraction airflow rate is reduced
which leads to system shutdowns. Debris had been noticed in other discharge lines and cleaned out,
so it was assumed that the discharge line for CS-GJ was getting clogged. Unfortunately, there was
no way to clean out the debris, thus a change order was approved to install a new condensate
discharge line from CS-GJ to the discharge sampling location (referred to as the "bucket').
Advance One installed a trench from CS-GJ to the bucket location to install a 2-inch DR11 HPDE
discharge/force main line. The trench was approximately 2.5-ft in depth and was backfilled/compacted
with native fill. The discharge line is equipped with five 2-inch wye clean -out locations to prevent
debris from getting clogged in the future. The path of the discharge line is illustrated on Figure 2 and
photo records stored in Appendix C.
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AECOM
Environment 13
4.0 Conclusions
Based on the tasks completed between November 2022 and February 2023 and an evaluation of
historic and current Site conditions, the following conclusions are made:
• AECOM oversaw LFG extraction system expansion activities such as drilling for four new
vertical extraction wells; trenching and pipe installation for one LFG header (2,400-ft);
trenching and repairs for one 80-ft LFG header; trenching and pipe installation for two
horizontal extraction wells (2,400-ft total) and eight horizontal wellheads.
• AECOM oversaw Advance One implement modifications for twenty-one existing LFG
extraction wells.
• AECOM oversaw installation of four condensate collection sumps (CS-16, CS-19, CS-25N,
and CS-54).
• There is evidence of back pressure (potential airlock) in the discharge lines connected to
CS-16, CS-25N, and CS-54 that limits condensate discharge. When the sumps are not able
to discharge, condensate in the sumps will overflow into the LFG header line and limit
vacuum to nearby extraction wells.
• Some sections of the northeastern HW contain less than 30-inches of topsoil (outlined in
brown on Figure 3), with the least amount of topsoil cover found between HW-103 through
HW-105 (approximately 12-inches). A lack of topsoil cover may allow ambient air to be
pulled in by the HW.
60620631 July 20, 2023

AECOM
Environment 14
5.0 Recommendations
Based on the information presented in this report, the following recommendations are made:
• It is recommended that LFG extraction operations continue at the Site. AECOM will
continually evaluate EW/HW performance and optimize its operation as system data is
collected.
• AECOM recommends installing relief valves (at high points) where there is evidence of
back pressure at condensate sumps (CS-16, CS-25N, and CS-54) and associated
extraction wells along the discharge network to assist with condensate discharge to the
Bucket (e.g., eliminate airlocks).
• Additional soil cover may be needed in areas where trash was encountered at shallow
depths and less than below 30 inches of soil cover was placed. These areas include the
northeastern HW and the western LFG header. Recommended locations for additional
topsoil cover are highlighted in Figure 3.
60620631 July 20, 2023

AECOM
Environment 15
6.0 References
AECOM, 2020. Wilders Grove Perimeter Methane Memo
60620631 July 20, 2023

Figures
Prepared for: City of Raleigh Solid Waste Services AECOM

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Appendix A
Prepared for: City of Raleigh Solid Waste Services AECOM

WELL ID DATE TIME %Methane --
ff�"
B037
1/19/2016
10:00
0.4
�
LLGRE,;{,RF
�5
B037
2/29/2016
9:45
11.9
1 , �
NO
WELL ID
DATE
TIME
% Methane
�'a
B037
3/23/2016
11:10
.8
0.0
B037
4/18/2016
11:00
B035
1/19/2016
9:52
38.0
"
B035
2/29/2016
9:36
1.6
41
B037
1 5/11/2016
9:46
0.1
L
B035
3/23/2016
11:00
3.6
B037
6/14/2016
10:28
0.0
0.0
B037
7/26/2016
9:07
B035
4/18/2016
10:35
6.8
B035
5/11/2016
9:49
0.0
= �"
B037
8/10/2016
9:52
0.0
B035
6/14/2016
10:30 6m
40.3
6037
9/7/2016
13:17
0.0
B035
7/26/2016
9:12
0.2
*'^' -'•
WELL ID
DATE
TIME
%Methane
B035
8/10/2016 1
9:56 1
0.0
0.0
w• t
t
_ _ .a
B035
9/7/2016 1137211
B002
1/19/2016
8:11
0.9
B002
2/29/2016
8:00
1.0
="
r
B002
3/23/2016
9:20
0.9
B002
4/18/2016
8:47
2.0
B002
B002
5/11/2016
6/14/2016
9:12
10:02
0.2
0.0
'E
B_1
B-37
B•l�_5
B-3
i
B002
7/26/2016
8:29
0.0
B002
8/10/2016
9:14
23.9
-+F_
B-4too �B•a3$.
/�
�� ,
-
B002 1
9/7/2016
10:14
0.0
WELL ID
DATE
TIME
-
% Methane
B001
1/19/2016
8:00
51.3
8-41
�• 4_�-�
_ _,
WELL ID
DATE
TIME
% Methane
B067
1/19/2016
11:35
0.1
B067
2/29/2016
12:10
0.2
B067
3/23/2016
12:55
41.7
B067
4/18/2016
1:00
1.0
B067
5/11/2016
8:51
0.0
B067
6/14/2016
8:35
0.0
B067
7/26/2016
8-.Nj
0.0
B067
8/10056
8:59
0.0
B067
9/7/2016
8:45
0.0
WELL ID
DATE
TIME
°/ Methane
B021
1/19/2016
9:36
0.0
B021
2/29/2016
9:25
0.0
B021
3/23/2016
10:47
0.0
B021
4/18/2016
10:25
1.8
B021
5/11/2016
10:04
0.0
B021
6/14/2016
9:31
0.0
B021
7/26/2016
10:19
0.0
B021
8/10/2016
10:19
0.0
B021
9/7/2016
13:44
0.0
B001
2/29/2016
7:55
64.8
B_ ® • -Z
B001
3/23/2016
9:15
55.9
B001
4/18/2016
8:44
53.3
B001
5/11/2016
9:08
52.4
1
B001
6/14/2016
9:58
55.3
42.6
ll
1$- B-5
B001
7/26/2016
8:25
B001
8/10/2016
9:09
42.0
.
L
B-43
B001
9/7/2016
10:09
32.0
B _2
►'
B-1
WELL ID
DATE
TIME
% Methane
B065
1/19/2016
11:30
31.7
B065
2/29/2016
12:05
45.0
B065
3/23/2016
9:05
59.4
B065
4/18/2016
8:42
41.1
B065
5/11/2016
9:05
3.0
B065
6/14/2016
9:55
8.8
B065
7/26/2016
8:21
31.8
B065
B065
8/10/2016
9/7/2016
9:04
9:00
17.6
0.9
WELL ID
DATE
TIME
% Methane
B064
1/19/2016
11:25
46.8
B064
2/29/2016
12:00
57.2
B064
3/23/2016
12:49
57.2
B064
4/18/2016
U-A
40.9
B064
5/11/2016
8:44
0.0
B064
6/14/2016
8:31
41.5
B064
7/26/2016
8:17
26.3
B064
8/10/2016
8:54
23.9
B064
9/7/2016
8:41
13.5
Q.
B-44
i B-64
p _ F
B-62
B-4'
El A
El r2'
".I.v
y I� - � Li• �-�7. `�
'r�k �,y �, f 7r •� E
B-52
2P a
.� LEGEND:
2016 Wake County Parcel
Approximate Extent of
Shallow Vent Trench
Structural Monitoring
`{
Structural Monitoring Location
WELL ID
DATE
TIME
% Methane
.
B020
1/19/2016
9:30
0.0
Perimeter Monitoring
`
B020
2/29/2016
9:18
55.1
B020
3/23/2016
10:36
55.1
Perimeter Well
B020
4/18/2016
10:20
0.8
B020
5/11/2016
10:00
0.1
Proposed Extraction Well
B020
6/14/2016
10:42
43.8
B020
7/26/2016
9:26
35.8_
O
Proposed Monitoring Point
B020
8/10/2016
10:14
22.9
B020
9/7/2016
13:39
32.1
&w w-
Surface Monitoring
_
❑
Marker Present
�.. WELL ID
DATE
TIME
o° Methane
B016
1/19/2016
9:20
40.0
No Marker Present
B016
2/29/2016
9:10
7.9
B016
3/23/2016
10:30
7.9
r
B016
4/18/2016
10:15
0.5
a' �;
Percent methane between 5 and 15
B016
5/11/2016
9:57
0.0
(between LEL and UEL)
B016
6/14/2016
10:39
8.5
B016
7/26/2016
9:21
0.5
rg
-
Percent methane greater than 15
B016
8/10/2016
1010
0.0
e =
v
(above UEL)
B016
9/7/2016
13.33
R0.0
WELL ID
DATE
TIME
% Methane
B043
1/19/2016
10:32
60.5
B043
2/29/2016
10:39
63.3
B043
3/23/2016
11:45
64.3
B043
4/18/2016
11:45
44.9
B043
5/11/2016
10:46
26.0
B043
6/14/2016
10:52
52.1
B043
7/26/2016
939
47.3
B043
8/10/2016
10:26
48.9
B043
I 9/7/2016
1 13:49
54.7
0 500 1,000
: h�
Feet
WELL ID DATE TIME _
% Methane
9.2
1.2
0.5
1.0
0.0
0.0
0.0
ar
NOTE: Locations are estimated based on previous surveys and historical
site figures.
Only monitored methane concentrations above the LEL in 2016 are displayed.
DATA SOURCE: Wake County GIS and ESRI
B048
1/19/2016
10:52
B048
2/29/2016
10:55
B048
3/23/2016
12:05
B048
4/18/2016
11:55
B048
5/11/2016
10:54
B048
6/14/2016
10:59
..
B048
7/26/2016
9:48
CITY OF RALEIGH
'
B048
8/10/2016
10:35
0.o
0.0
B048 9l7/2016
13:57
WILDERS GROVE CLOSED LANDFILL
MONITORING LOCATIONS
DATE:1/31/2018
SHEET:
DRAWN BY: M. SMITH
CHECKED BY:
k
-�
` r
A_COM
JOB NUMBER: 60393858

Appendix B
Prepared for: City of Raleigh Solid Waste Services AECOM

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LANDFILL GAS EXTRACTION
SYSTEM MODIFICATION
AS=BUILT PACKAGE
WILDERS GROVE LANDFILL
CITY OF RALEIGH , NORTH CAROLINA
LOCATION MAP
WILDERS G�IRDVE
Walgreens
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SITE DATA
#' SHEET INDEX
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PROJECT: LANDFILL GAS EXTRACTION
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TITLE AND INDEX
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SYSTEM MODIFICATION
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Raleigh Beach ROE
ADDRESS: 900 NORTH NEW HOPE ROAD
2
AS -BUILT LFG EXTRACTION SYSTEM
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EDGEW
RALEIGH, WAKE COUNTY, NORTH CAROLINA
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MODIFICATIONS
PROPERTY OWNER: CITY OF RALEIGH
P.O. Box 590
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AS -BUILT LFG EXTRACTION SYSTEM
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RALEIGH, NORTH CAROLINA 27602
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21" DR-11 HDPE
BLIND FLANGE
21" NEOPRENE GASKET
21" DR-11 HDPE
FLANGE ADAPTER
WITH SS BACKUP
FLANGE
BOLTS AND NUTS
; BACKUP FLANGE
6" DR-11 HDPE
STICK-UP PIPE
BACK-UP FLANGE REGULATOR AND
PRESSURE GAUGE
'INGS
I
'IPE
NOTES:
1. DIAMETERS ARE BETWEEN 21-INCHES TO 24-INCHES AND DEPTH BETWEEN
8'-10' BELOW THE LOWEST HEADER. EACH SUMP HAS A CAPACITY OF 24 CF AND IS
EQUIPPED WITH QED PUMPS.
2. DEPTH FROM BOTTOM OF FLANGE TO GRADE RANGED FROM 6-INCHES TO
12-INCHES.
3. AIR SUPPLIED FROM NEAREST VIABLE CONNECTION POINT TO NEW
CONDENSATE SUMP. EXISTING LINES VERIFIED FOR SUFFICIENT FOR PUMPING
OUT CONDENSATE PRIOR TO CONNECTION.
4. FLUID DISCHARGE ROUTED TO NEAREST VIABLE CONNECTION POINT.
CONNECTIONS TO EXISTING FLUID DISCHARGE ARE FIT WITH 2" CHECK VALVES
ON BOTH UPSTREAM FLUID DISCHARGE PIPES.
5. CONDENSATE SUMPS CS-15 AND CS-54 INSTALLATIONS REQUIRED
DISTURBING THE EXISTING GEOMEMBRANE LINING AT THE LANDFILL TO ALLOW
FOR BORING AND EXCAVATION WORK. LANDFILL LINER AND GEOMEMBRANE
WAS REPATCHED AND SEALED USING LANDTEC WELLBORE SEAL PIPE BOOTS
AND GEOMEMBRANE.
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Appendix C
Prepared for: City of Raleigh Solid Waste Services AECOM

12-15-2022p"
D . .
1 0-inch gear operated
for western LFG header.
J
s u�

Photo Date:
No.
4 01-31-2023
Description:
QED LFG Extraction
Wellhead (EW-55)
.f
_< y

Photo Date:
No.
F 01-31-2023
Description:
Discharge Line with 2-
inch Wye clean -out
points on new
discharge/force main
line.
lop

PHOTOGRAPHIC RECORD
Client Name:
Site Location:
Project No.
City of Raleigh
Wilder's Grove Landfill Gas Extraction System
60620631
Photo
No.
7
Date:
02-23-2023
-
Description:
Condensate Sump (CS-
�e
16)
g{.
k
E: