3405_Forsyth_RJR_RuralHall_Indus_SedimentExcavationPlan_FID1415789_20200617

ERM FRN Inc. F—erm.com
hone: [phone]
Summit Avenue [phone]
NC 28203
16 June 2020
North Carolina Department of Environmental Quality
Division of Waste Management
1646 Mail Service Center
Raleigh, North Carolina 27699-1646
Attention: Ms. Jaclynne Drummond
[e-mail]
Via Email
Reference: 0545821
Subject: Sediment Boil — Excavation Plan
Permit #34-05 - Edwards Road Landfill
Edwards Road
Rural Hall, Forsyth County, North Carolina
Dear Ms. Drummond:
On behalf of R.J. Reynolds Tobacco Company (RJRT), ERM NC, Inc. (ERM) is providing this
excavation plan to conduct additional assessment/investigation activities in the area of a surface
boil encountered at the Edwards Road landfill in Rural Hall, NC.
The boil, located on the eastern slope of the landfill immediately west of sediment trap ST-1, was
discovered February 10, 2020 during a routine post -closure quarterly inspection. Following
discovery of the boil, immediate measures were put in place to contain the area surrounding the
boil to prevent uncontrolled sediment -laden runoff into sediment trap ST-1. Since initial discovery,
it appears the surface boil is sporadic in nature (not continuous) responding to rainfall events with
surface flow.
Due to above average wet conditions in the area, field investigation activities have been delayed
until dryer conditions are available to conduct field work. Refer to attached updated figure for the
location of features and orientation. Proposed activities will include the following:
Initial steps
Mobilization of field team and excavation contractor.
o Equipment will consist of shovels, steel rakes, brooms, buckets and low
ground pressure mini -tracked excavator.
Conduct onsite health & safety meeting with assembled team to review proposed
activities for the day. The importance of liner system protection will be stressed
during the meeting.
Recordation of boil location at time of activities. Measurements will be taken
relative to the nearby anchor trench drain markers.
Prior to any excavation activities, water levels in piezometers placed along the
eastern containment berm will be gaged. Excavation may continue as long as any
measured water levels are below 4 feet of ground surface.
Page 1 of 5

ERM
16 June 2020
Reference: 0545821
Page 2 of 5
• The mini -tracked excavator will be used to remove the upper 1-foot of cover soils
in the area of the boil and continue westward towards the liner anchor trench.
• Using hand tools, the remainder of cover soils will be removed to expose the
underlying anchor trench and liner system.
• Exposed liner system and anchor trench will be cleaned with brooms for visual
inspection.
• Using the previous field measurements, the location of the boil will be marked with
a wooden stake or pin flags.
• The exposed liner system and anchor trench will be visually inspected to identify
any apparent defects and evidence of flow from beneath the liner system.
• The nearby anchor trench drain (immediately south of boil) will also be exposed to
inspect integrity of the drain system and verify the drain is functioning
appropriately.
Based on field observations, when active, the boil contains dark gray sediments. The dark gay
color may be used to trace boil flow towards the source of flow. The following describes
anticipated activities based on results of the initial steps.
Dark gray color present above boil area (west)
• Using the mini -excavator, remove the upper 1 foot of cover soils upgradient of boil
area (west towards landfill cap). The remaining cover soils will be removed using
hand tools to expose the liner system. Based on evidence of flow direction from
observation of dark gray sediments along the surface, proceed along the direction
of sediments at 10-foot increments.
• The surface of the liner system will be visibly inspected for evidence of dark gray
sediment flow.
• If evidence of flow continues upgradient, continue excavation at 10-foot
increments.
• If observations indicate an origination point of dark gray sediments, stop
excavation activities.
• Cut geocomposite drainage material above liner in order to fold geocomposite
material back to visually inspect liner.
• Visually inspect liner for defects and evidence of flow.
• If defect is found, stop activities to schedule liner repair.
• This activity will not extend beyond 50-ft of boil area. If evidence of sediment
continues upgradient in excess of 50-ft, consider non-invasive investigation such
as electronic leak location survey (ASTM D 7007).
Dark gray color confined only to boil area
• The area surrounding the boil area should have been exposed to liner
limits/anchor trench during "Initial steps". If flow direction appears evident from
observation of dark gray sediments beyond the excavated area, remove additional
cover soils using the mini -excavator to remove the upper 1 foot of cover soils.

ERM
16 June 2020
Reference: 0545821
Page 3 of 5
The remaining cover soils will be removed using hand tools to expose the liner
system. Soils will be removed to expose the anchor trench liner as well.
• Visually inspect excavated areas east of anchor trench (towards sediment basin)
for evidence of gray sediments beneath original ground surface.
• From these activities we anticipate two possible scenarios; 1) sediments do not
extend beyond west side (towards landfill cap) of or within anchor trench; 2)
evidence of sediments are observed beyond anchor trench limits (west of anchor
trench towards landfill cap)
o Scenario 1 — Indicates source from within anchor trench
■ Remove stone from anchor trench in area of gray sediments.
■ Visually inspect liner within anchor trench for any defects.
■ If defect is found, stop activities to schedule liner repair.
o Scenario 2 — Indicates source area originates below landfill cap liner system
■ Using a combination of mini -excavator and hand tools, remove soil from
behind (east side) of anchor trench limits; outside of liner limits.
■ Remove stone from anchor trench in the area of investigation; stockpile
stone to be placed back into anchor trench.
■ The length of soil and stone removal will depend on ability to lift liner out of
anchor trench to allow for visual inspection.
■ Lift liner from anchor trench and roll back onto upgradient slope (west) to
allow for visual inspection.
■ Photo document and record indications of dark gray sediments; direction
and estimated orientation towards source area.
■ Do not extend these investigation activities more than 5 feet east (towards
sediment basin) beyond anchor trench to preserve berm integrity.
In all cases, disturbed areas will be returned to original grade using soils from investigative efforts
and onsite stockpiled soils. Areas will be seeded with straw following re -grading activities.
Results of Field Investigation Activities
All activities will be documented including photographs for appropriate reporting and discussions
with R. J. Reynolds and NCDEQ. From these proposed field investigation activities, we anticipate
one of the following outcomes:
• A defect in the liner system was located and repaired appropriately
• A defect could not be located within the liner system visually, requiring execution
of an electrical leak location survey (ASTM D 7007). Defects discovered from
leak location survey were exposed and repaired.
• Evidence indicates a source area of gray sediments is located beneath the liner
system beyond limits of field investigation activities. For this case, additional
evaluation will be needed to assess potential causes of a source area and
appropriate additional investigative measures.

ERM
16 June 2020
Reference: 0545821
Page 4 of 5
Please contact Mr. Max Hopkins of R.J. Reynolds Tobacco Company at 336-741-6932 or me if
you have any questions or comments.
Sincerely,
el,
Dave Wasiela, P.E.
Project Engineer
Attachments:
Figure
AAlan actin, P.G.
Project Manager
cc: Mr. Scott Snow — R.J. Reynolds Tobacco Company
Mr. Max Hopkins — R.J. Reynolds Tobacco Company
Mr. Tom Wilson — ERM

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R.J.Re}maldsTobacco Co.
Rural Hall, North Carolina