WS-2446_3355_CA_RPTS_20150608

June 8, 2015

North Carolina Department of Environment and Natural Resources Attention: Thomas Moore, Hydrogeologist II
Division of Waste Management, UST Section
585 Waughtown Street Winston Salem, NC 27107
RE: Site Assessment Report and Modified CAP
Three Boys Citgo (former Gant #31 Station) 5,000 Old Walkertown Road
Winston-Salem, NC
Incident #3355, Facility # 0-016565
Dear Mr. Moore;
ENVIRON Engineers of North Carolina, PC (ENVIRON) is pleased to submit this report, on
behalf of the Gant Oil Company (Gant), which includes results of weekly-to-biweekly free phase product gauging and recovery events initiated since October 2, 2012, dissolved phase gasoline
and oil contaminant concentrations and respective isoconcentration maps, groundwater contour maps, forensic evaluation of LNAPL analytical results and historical trends in dissolved phase contaminant concentrations, and a comprehensive survey of existing drinking water wells within
a 1,500 feet radius of the site. A conceptual site model has been developed pertaining to release sources, migration pathways and risk potential. Based on the information obtained,
ENVIRON has prepared a Corrective Action Plan (CAP) for the removal of free phase product at
the site. A brief summary of findings is presented below.
EXECUTIVE SUMMARY
• The gauging of all site wells on October 2, 2012 detected the presence of 1 foot and 10 feet of red-dyed oil in monitoring well B-5 and recovery well RW-6, respectively, located in close proximity of the existing kerosene and diesel fuel underground storage tanks (USTs). No
other wells contained evidence of free product.
• ENVIRON instituted weekly-to-monthly gauging and hand bailing of free product until free
product thickness was reduced to 0.2 and 0.6 feet in wells B-5 and RW-6, respectively. The frequency of these gauging and recovery events was based on free product thickness, which was shown to be indirectly related to the groundwater table elevation at the site. A
total of approximately 31 gallons of oil has been recovered by ENVIRON via hand bailing from October 2, 2012 to April 23, 2015. The area exhibiting free product was estimated to be
700 square feet in size as defined by wells B-5 and RW-6, and nearby wells exhibiting the
absence of free product and lower levels of dissolved phase contamination compared to B-5 and RW-6.
• Groundwater flow direction was determined to occur in an easterly direction in the western portion of the site trending to a southeasterly direction in the central and eastern portions of
the site. Depth to groundwater ranged from 24 feet in the northwest corner of the site to 30
feet in the southeastern portion of the site.
• The laboratory analysis of groundwater samples for volatile petroleum hydrocarbon (VPH)
and extractable petroleum hydrocarbon (EPH) fractions and target analytes provided
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information that was used to define three separate dissolved phase contaminant plumes; one originating from the kerosene and diesel fuel UST area; one from the gasoline fuel
dispenser area; and one from the former gasoline UST area. All three plumes were shown
to extend in a southeasterly direction beneath Old Walkertown Road and a railroad right-of-way located south of the site.
• A large asphalt parking lot used by the railroad for the loading and unloading of vehicles is located hydraulically downgradient and southeast of the site. No drinking water wells are
located southeast and downgradient with respect to groundwater flow within 1,500 feet of the site. While a municipal drinking water system is available for the subject area, a total of eight properties located within 125 feet to 1,200 feet west and south of the site are known
that either rely on private wells for potable water or have wells that have not been properly abandoned.
• Information supporting the occurrence of additional releases of diesel fuel and gasoline at
the site, since that reported in the 1980s, was obtained based on a review of tank testing records, forensic fingerprint analysis of free product, presence of red-dyed free phase diesel
fuel, and a forensic assessment of the degree of weathered dissolved phase petroleum compounds. The absence of the detection of ethanol in groundwater samples collected at the site in October 2012, passing tank and line testing results in 2012 and the limited extent
of the free product oil plume suggests that tank system releases are not currently ongoing.
Given that dissolved phase contaminant plumes are not migrating towards human or ecological
receptors and that evidence supporting ongoing releases of petroleum products has not been
obtained, implementation of active remedial technologies to address groundwater contaminants is likely to be both exceedingly expensive and an inefficient means of achieving additional risk
reduction in residual dissolved phase contaminant concentrations above that expected to occur
from natural attenuation mechanisms alone.
ENVIRON proposes the recovery and reduction of free product (diesel and/or kerosene) to less
than 1/8 inch in site wells as the primary remedial closure strategy for the site. Ideally, the most effective approach at removing the residual free product at the site would be to remove the kerosene and diesel fuel USTs and dispenser island to permit access to and recovery of oil-
saturated soils, and the recovery of free product via a combination of vacuum enhanced
extraction utilizing the existing network of recovery wells and the injection of the non-ionic surfactant Biosolve Pinkwater. The current site owner has agreed to the removal of the
kerosene and diesel fuel USTs and dispenser island.
Should you have any questions concerning the information presented in this report, please contact Bruce Tease at [phone].
Sincerely ENVIRON Engineers of North Carolina, PC

__________________________ __________________
Russell S. Kemp, PE Bruce Tease, PhD Vice President Senior Manager

BT/RK/cl
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Signature and Environmental Professional Statement
“I certify that I am a qualified groundwater scientist who has received a baccalaureate or post-
graduate degree in the natural sciences or engineering, and have sufficient training and
experience groundwater hydrology and related fields, as demonstrated by state registration and
completion of accredited university courses, that enable me to make sound professional
judgments regarding groundwater monitoring and contaminant fate and transport. I further
certify that this report was prepared by myself or by a subordinate working under my direct
supervision.”

___________________________________
Bruce Tease, PhD Senior Manager

LIMITATIONS
This Corrective Action Plan has been prepared exclusively for use by the Gant Chemical
Company and may not be relied upon by any other person or entity without ENVIRON’s express written permission. The conclusions presented in this report represent ENVIRON’s best
professional judgment based upon the information available and conditions existing as of the
date of our review. In performing its assignment, ENVIRON must rely upon publicly available information, information provided by our client and/or their legal counsel, and information
provided by third parties. Accordingly, the conclusions in the report are valid only to the extent that the information provided to ENVIRON was accurate and complete. ENVIRON therefore makes no warranties about the condition of the site. This report is not intended as a substitute
for legal advice.

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Contents
Page
1 INTRODUCTION 6
2 FINDINGS 6
2.1 Inventory of Monitoring and Recovery Wells and Remedial Equipment 6
2.1.1 Monitoring and Recovery Wells 6
2.1.2 Remedial Equipment 7
2.2 Groundwater and Free Phase Product Gauging and Recovery 8
2.2.1 Groundwater Gauging 8
2.2.2 Free Product Gauging and Recovery 8
2.3 Dissolved Phase Contaminant Concentrations and Plume Delineation 9
2.3.1 Summary of Groundwater Sampling and Analytical Results 9
2.3.2 Dissolved Phase Groundwater Contaminant Plume Delineation 9
2.4 LNAPL Source Evaluation 10
2.4.1 Evidence Supporting the Absence of Ongoing Releases 11
2.4.2 Evidence Supporting Additional Historical Releases 11
2.5 Drinking Water Well Inventory 14
3 CONCEPTUAL SITE MODEL 14
3.1 Site Environmental Conditions 16
3.2 Extent of Contamination 17
3.3 Human and Ecological Receptors 17
4 CONCLUSIONS 18
5 RECOMMENDATIONS 20

LIST OF FIGURES
Figure 1: Site Location Map
Figure 2: Site Plan
Figure 3: Groundwater Contour Map for October 11, 2012
Figure 4: Groundwater Contour Map for October 22, 2012
Figure 5: LNAPL Thickness and Recovery vs. Groundwater Table Elevation
Figure 6: MTBE Isoconcentration Map
Figure 7: Total VPH Fraction Isoconcentration Map
Figure 8: Total EPH Fraction Isoconcentration Map
Figure 9: 2-methylnaphthalene Isoconcentration Map
Figure 10: Trends in Dissolved Phase BTEX and MTBE Concentrations at B-9
Figure 11: Historical Trends in LNAPL Thickness and Groundwater Table Elevation
Figure 12: Site Plan of Drinking Water Wells within 1,500 feet of Site
Figure 13: Graphic Representation of Conceptual Site Model
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Figure 14: LNAPL Plume Site Plan
Figure 15: Gant Chart
LIST OF TABLES
Table 1: Well Construction and Groundwater Table Elevation Measurements
Table 2: LNAPL Thickness, Recovery and Groundwater Table Elevations
Table 3: Summary of Low Flow Groundwater Sampling Measurements
Table 4: VPH Fraction and VOC Target Analyte Results
Table 5: EPH Fraction and PAH Target Analyte Results
Table 6: Drinking Water Well Information
Table 7: LNAPL and Depth to Groundwater
APPENDICES
Appendix A: Photographs
Appendix B: Waste Manifest
Appendix C: Tank Testing Reports
Appendix D: Apex and Laboratory Analytical Reports and Chain of Custody
Appendix E: Soil Boring and Groundwater Sampling Logs
Appendix F: Corrective Action Plan
Appendix G: Site Specific Health & Safety Plan

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1 INTRODUCTION
ENVIRON Engineers of North Carolina, PC (ENVIRON) was contracted by Gant on August 31,
2012, to conduct environmental investigations at the former Gant #31 station located at 5,000 Old Walkertown Road, Winston Salem, Forsythe County, North Carolina and depicted on the
site location map presented as Figure 1. The investigations conducted by ENVIRON represent
the first monitoring of site conditions since the limited groundwater sampling and analytical testing conducted by Advanced Environmental Technologies (AET) in 2010 on behalf of the
former gasoline station operator Exprezit! Convenience Stores, LLC (Exprezit!) of 348 Miracle
Strip Parkway, Suite 26, Fort Walton Beach, FL.
Gant operated the station prior to Exprezit! at the time releases of kerosene and gasoline were
reported to the North Carolina Department of the Environment and Natural Resources (NCDENR) by Catlin Engineers & Scientists (Catlin) in 1987. According to the Forsyth County Tax Assessors office records, Khoury & Lokas Properties purchased the site property on
December 7, 2011, from Carol M. Westmoreland, and now operate the station and convenience known as Three Boys CITGO.
It is ENVIRON’s understanding that the NCDENR has assigned a high risk rating to the site,
based on their letter dated December 10, 2007, which cited the continued presence of free product thickness exceeding the regulatory threshold of 1/8 inch in monitoring wells at the site
where active private drinking water wells exist within a radius of 1,500 feet of the site.
This report includes results of weekly-to-monthly free product (i.e. kerosene or diesel fuel) gauging and recovery events, dissolved phase gasoline and oil contaminant concentrations and
respective isoconcentration maps, groundwater contour maps, forensic evaluation of LNAPL
analytical results and historical trends in dissolved phase contaminant concentrations, and a comprehensive survey of existing drinking water wells within a 1,500 feet radius of the site. A
conceptual site model has been developed pertaining to release sources, migration pathways
and risk potential. Based on the information obtained, ENVIRON has prepared a Corrective Action Plan (CAP) for the removal of free phase product at the site.

2 FINDINGS
2.1 Inventory of Monitoring and Recovery Wells and Remedial Equipment
2.1.1 Monitoring and Recovery Wells
An inventory of accessible monitoring wells (MW), recovery wells (RW), soil vapor extraction
(SVE) points and air sparge points (AS) revealed the presence of thirteen (13) 2-inch diameter
monitoring wells; nine (9) soil vapor extraction points within thirteen (13) recovery well
enclosures (2 x 2 feet metal vaults). Eight (8) of the RWs are located south of the site between
Old Walkertown Road and a railroad right of way and consist of deeper sumps capped with
manhole covers ranging in depth from 2.5 feet to 5.5 feet (RW-7) below grade. Stainless steel
total fluids pneumatic displacement pumps were observed in six (6) RWs. The pumps and
tubing were removed from the RWs, to permit groundwater gauging and sampling, and placed
in a locked-fenced enclosure located immediately north of the site building.
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The monitoring wells were completed with flush mounted well head protection boxes, except for
B-6 which has an iron stand pipe extending approximately 3 feet above grade and B-8 which is
located below a 2 feet x 2 feet metal plate. Monitoring wells B-10, 14, 17 and 19 were not
located and presumed destroyed. Monitoring well B-20 was not observed due to its location
south of Old Walkertown Road in a gated paved lot used for the off-loading of vehicles from
freight cars. The condition of this well remains unknown. Monitoring well B-15 was located but
could not be opened based on an odd sized 5-sided locking well cap that could not be removed
without destroying the well head. The proximity of this well north and upgradient of the source
areas did not warrant its restoration. Several well heads were missing well caps and numerous
well boxes were not equipped with secured covers (i.e. no bolts or provisions for such).
ENVIRON provided 16 wells with gripper caps.
A total of 7 air sparge (AS) points with flexible hosing were observed on the station property
within metal vaults with lids.
ENVIRON conducted a level survey of accessible monitoring and recovery well heads on
October 11, 2012. The well head elevations are based on an assumed benchmark elevation of
100.00 feet (stand pipe rim at B-6).
Table 1 summarizes the various monitoring and recovery well installations along with
construction date, maximum well depth, screen interval depth range (obtained from Catlin and
AET reports), PVC well casing diameter, and well head elevations. Figure 2 is a site plan
prepared by ENVIRON showing the location of the above noted well points based on plans
presented in the February 2011 report by AET, a 2012 aerial photograph of the site and
ENVIRON observations.
2.1.2 Remedial Equipment
The remedial equipment previously installed at the site by others was a combination of
groundwater pump and treat, air sparge and soil vapor extraction technologies. The following
remediation equipment was observed in a locked fence enclosure immediately north of the site
convenience store building:
• Large volume oil/water separator tank;
• Approximately 8-10 feet air stripper tower;
• 5 HP blower;
• One 275 gallon AST containing approximately 66 gallons of waste petroleum (1 feet);
• Electrical control panel;
• 15 HP rotary screw air compressor and control panel for the pneumatic displacement pumps
located in the recovery wells;
• Two approximately 55 gallon granular activated liquid carbon canisters;
• 20 HP positive displacement blower for SVE points;
• Miscellaneous equipment in three metal enclosures (pumps, compressors);
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The condition of most of the mechanical equipment was noted to be in substantial disrepair,
except for the blower and pneumatic displacement pumps. The unknown condition of
subsurface transmission lines and the rusted appearance of the mechanical equipment suggest
that the remedial equipment should not be operated. Photographs of the remedial equipment,
site and surrounding areas are included in Appendix A.
2.2 Groundwater and Free Phase Product Gauging and Recovery
2.2.1 Groundwater Gauging
ENVIRON measured the depth to groundwater and maximum depth of monitoring and recovery
wells using interface probes on October 2, 11 and 22, 2012. Depth to groundwater ranged from
24 feet in the northwest corner of the site to 30 feet in the southeast portion of the site.
Groundwater flow was determined to occur in an easterly direction in the western portion of the
site, trending to the southeast in the central and eastern portions of the site. Groundwater
measurements are summarized in Table 1. Figures 3 and 4 depict groundwater contours
based on the October 11, 2012 and October 22, 2012, gauging data.
2.2.2 Free Product Gauging and Recovery
Free product was detected on October 2, 2012, in monitoring well B-5 (0.5 feet) located
between the existing kerosene and diesel fuel USTs, and recovery well RW-6 (10 feet) located
south of B-5. The free product in both wells was clear red in color and physically consistent with
oil and not gasoline. No other site wells exhibited evidence of free product.
Product and groundwater recovered during hand bailing events is collected in a 5 gallon plastic
bucket and transferred to a 55 gallon steel drum contained in an 80 gallon overpack drum
located on site in the locked remedial equipment fenced enclosure north of the site building.
ENVIRON gauged depth to groundwater and free product thickness, and hand bailed free
product (until thicknesses were reduced to 0.2 feet and 0.6 feet in wells B-5 and RW-6,
respectively) on a weekly to monthly basis, depending upon product thickness. Depth to
groundwater, product thickness and volumes of oil recovered by ENVIRON via hand bailing at
B-5 and RW-6 are summarized in Table 2 and depicted in Figure 5. A total of approximately 31
gallons of oil was recovered by hand bailing from both wells between October 2, 2012 and April
23, 2015. A total of approximately 314 gallons of oil and impacted groundwater from free
product collection, purge water from well sampling and oil from an on-site 275 gallon
aboveground tank have been disposed of since ENVIRON initiated free product recovery in
October 2012. Waste manifests are included in Appendix B.
The area of the free product plume was estimated to be approximately 700 square feet in size
as defined by wells B-5 and RW-6, and nearby wells exhibiting the absence of free product, and
low levels of dissolved phase contamination compared to B-5 and RW-6. Routine gauging of
nearby wells indicates the free product is limited to B-5 and RW-6, and hence stable. Additional
information concerning plume stability is discussed in the conceptual site model (Section 3) and
correction action plan (Attachment F) presented herein.

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2.3 Dissolved Phase Contaminant Concentrations and Plume Delineation
2.3.1 Summary of Groundwater Sampling and Analytical Results
ENVIRON collected groundwater samples from 11 well points (B-4, 8, and 16; RW-1, 3, 4, 5, 8,
11, 12 and 13) via the US EPA Low Flow Sampling Method on October 22, 23 and 24, 2012.
Submersible pumps were used to recover groundwater due to the depth to groundwater
exceeding 25 feet in the site wells. Groundwater quality data (temperature, pH, conductivity
(uS/cm), ORP (eV), Disslved Oxygen (mg/l)) was collected at 5 minute intervals using a YSI 556
sensor with a flow-through cell. Turbidity (NTUs) was also measured at similar time intervals
using a LaMotte turbidity meter.
Groundwater sampling rates ranged from 100 milliliters per minute (ml/min) to 500 ml/min, with
an average flow rate of 230 ml/min among all wells. Groundwater table elevation changes were
limited to less than 1 foot except at RW-12 where the groundwater table elevation dropped 2.6
feet during sample collection. Turbidity ranged from 0.2 to 9.8 NTUs with an average of 5.2
NTUs. The pH ranged from 4.5 to 6.8, with an average value of 5.7. A summary of the water
quality data recorded after achieving equilibrium is presented in Table 3.
Due to the presence of free product at B-5 and RW-6 during the October 22-24, 2012 sampling
event, groundwater samples were collected from B-5 and RW-6 using disposable hand bailers
without well purging on October 24, 2012. Groundwater located beneath the layer of free
product in translucent plastic bailers was drained from the base of the bailer into laboratory
provided sample containers to avoid disturbing the free product layer and minimizing the
collection of free product where possible. Samples of groundwater were collected beneath the
free product in order to obtain dissolved phase contaminant concentrations that were used to
identify product type and assist in trend analyses.
Due to the absence of sufficient groundwater at RW-9 and RW-10 during the October 22-24,
2012 sampling event, groundwater samples were collected on November 5, 2012, using hand
bailers.
Groundwater samples collected via low flow methods were submitted to Prism Laboratories, Inc.
of Charlotte, NC via laboratory currier on October 24, 2012. Samples collected via hand bailers
were submitted to Prism on October 26, 2012 (B-5 and RW-6) and November 6, 2012 (RW-9
and RW-10). All samples were analyzed for volatile petroleum hydrocarbon (VPH) and
extractable petroleum hydrocarbon (EPH) fractions and target analytes via MassDEP Methods,
VOC target analytes via Method SM6200 B and PAH target analytes via EPA Method 625.
Analytical results for VPH Fractions and VOC Target Analytes are summarized in Table 4, with
results for EPH Fractions and PAH Target Analytes summarized in Table 5.
2.3.2 Dissolved Phase Groundwater Contaminant Plume Delineation
Isoconcentration maps were generated for the Total VPH Fraction, Total EPH Fraction, MTBE
and 2-methylnaphthalene concentrations detected in groundwater samples collected during the
October and November 2012 sampling events. The Total VPH fraction and MTBE data
represent gasoline related plumes and the Total EPH Fraction and 2-methylnaphthalene data
represent oil related plumes.
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2.3.2.1 Gasoline Impacted Groundwater Plumes
The Total VPH Fraction isoconcentration plume map (Figure 6) depicts two distinct plumes
migrating in a southeasterly direction from the former gasoline UST area and the current
gasoline dispenser area. Both plumes exhibit a slug of higher contamination at the most
downgradient well locations, indicative of historic release conditions, with lower concentrations
in the vicinity of the likely source areas.
The groundwater samples collected from RW-3, -4, - 6,-8, -9, -10 and -13 exceed the C5-8 VPH
fraction regulatory limit of 400 ug/l. There are no NCDENR standards for the other VPH
fractions.
The MTBE isoconcentration map (Figure 7) depicts a gasoline-specific contaminant plume that
coincides somewhat with the easternmost Total VPH Fraction plume with a similar
downgradient slug of contamination. The MTBE plume extends from both the former gasoline
UST and existing gasoline dispenser areas.
Low levels of MTBE (78 to 190 ug/l) exist south of the dispensers whereas concentrations as
high as 19,000 ug/l and 5,300 ug/l exist further southeast, indicating the direction of
groundwater contaminant transport and a more historical release of gasoline containing MTBE
as an additive. Ethanol was not detected in any of the groundwater samples collected. The
NCDENR standard for MTBE is 20 ug/l. Benzene, total xylene and naphthalene standards of 1
ug/l, 500 ug/l and 6 ug/l, respectively are also exceeded at the site.
2.3.2.2 Oil Impacted Groundwater Plumes
The Total EPH Fraction isoconcentration map (Figure 8) depicts an oil specific contaminant
plume migrating in an easterly direction from the kerosene and diesel fuel UST area, with the
highest concentrations contained in the immediate area of RW-6 and B-5, the wells exhibiting
free phase oil. Individual EPH Fraction concentrations in groundwater samples collected from
other site wells were below their respective regulatory limits of 200 to 10,000 ug/l except for the
C11-22 EPH fraction concentrations of 950 ug/l at RW-4, 550 ug/l at RW-10 and 240 ug/l at
RW-9, which exceed the 200 ug/l standard.
The 2-methylnaphthalene isoconcentration map (Figure 9) depicts a contaminant plume unique
to oil that coincides with the Total EPH Fraction plume, but extends somewhat further
downgradient, as would be expected based on a greater water solubility (26,000 ug/l) than the
majority of compounds comprising the EPH fractions, which have much lower water solubility
(10 to 5,800 ug/l). The 2-methylnaphthalene plume extends from the kerosene and diesel fuel
oil UST area to RW-9 (93 ug/l) and RW-10 (120 ug/l) at concentrations exceeding the regulatory
limit of 30 ug/l.
2.4 LNAPL Source Evaluation
A review of tank testing reports, forensic fingerprint analytical results of free product samples
collected from B-5 and RW-6, historical institution of red-dye in diesel fuel and kerosene, and
the degree of weathered dissolved phase concentrations of the indicator compounds benzene,
toluene, ethylbenzene and xylenes (BTEX) was performed to assess the source of the LNAPL
present at the site and to ascertain whether product releases are ongoing.
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2.4.1 Evidence Supporting the Absence of Ongoing Releases
The absence of the detection of ethanol in groundwater samples collected at the site in October
2012, and the passing of tank and product line tightness testing in October 2012 support the
absence of ongoing UST system releases at the site. The presence of higher gasoline
contaminant concentrations further downgradient of potential source areas further supports the
absence of ongoing releases, given that higher contaminant concentrations are expected to be
found closer to an ongoing release source.
More recent dissolved phase BTEX concentrations in groundwater samples collected from
monitoring well B-9 (immediately southeast of gasoline fuel dispenser pad) demonstrate
considerable weathering based on the ratio of the sum of the more water soluble constituents,
benzene and toluene, to the least water soluble ethylbenzene and xylenes (see Figure 10).
Recent gasoline releases typically demonstrate a dissolved phase concentration ratio of 6.0 with
lower values correlated to a greater degree of weathering; ratios of 0.2-0.9 represent
substantially weathered conditions (Kaplan et al 1997).
The highest dissolved phase oil concentrations were detected in samples collected from wells
B-5 and RW-6, which coincide with the free product plume associated with the kerosene and
diesel fuel USTs. The lower concentrations of dissolved phase oil related compounds further
downgradient of B-5 and RW-6 demonstrate the limited migration of oil at the site.
The UST systems are reportedly equipped with an automated Veederoot alarm system,
according to the current site owner. No alarm conditions have been reported according to the
site owner since taking ownership in December 2011.
2.4.2 Evidence Supporting Additional Historical Releases
Given the persistence and amount of free phase product remaining at the site after releases of
gasoline and kerosene were first reported to the NCDENR in 1987, an evaluation of the
potential for additional release(s) of petroleum products at the site was performed by ENVIRON.
2.4.2.1 Gasoline
Despite the detection of elevated concentrations of gasoline related compounds (based on
BTEX concentrations) in 1988, low levels of MTBE were detected in groundwater samples
collected downgradient of the former gasoline USTs (24 ug/l) and fuel dispensers (28 ug/l)
suggesting the absence of gasoline formulated with elevated levels of MTBE (see Figure 11).
MTBE was not tested for in subsequent groundwater investigations until 2001, when elevated
levels of MTBE were reported suggesting an additional release of gasoline occurred sometime
between 1988 and 2001.
Spikes in BTEX ratios of over 5 in 1995-1996 and to a lesser degree (1.5) in 2004 were noted
following a review of groundwater analytical data for samples collected from B-9 indicating a
shift in higher benzene and toluene levels compared to the less mobile and more recalcitrant
ethylbenzene and xylene (see Figure 10). Such conditions would be consistent with a more
recent release of product from the gasoline dispensers.
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2.4.2.2 Kerosene and Diesel Fuel
A review of past free product gauging records for wells located in the area immediately south of
the kerosene and diesel fuel USTs (B-3 for March 1987 to March 1997 and RW-6 for November
1995 to November 2012) revealed that a substantial reduction in free product thickness
occurred after its initial detection in 19871. Product thickness at RW-6 of less than one foot
persisted until 1997 when it rebounded to 2 feet, and then to 9 feet in 2008, and 10 feet in 2012.
The increase in product thickness may be attributed to the shutdown of the remediation system
beginning around 1998, despite efforts to restart it in 2000-2001.
In general, it is not uncommon for an increase in free product thickness to occur in monitoring
wells after a dramatic fluctuation in groundwater table elevation, typically following a substantial
drop in the groundwater table, which promotes the downward movement of free product (via
gravitational forces) into the void space of unsaturated soil pores and monitoring wells.
However, there was not a distinct correlation between groundwater table elevation and free
product thickness based on the data available. While the absence of gauging data from 1998 to
2008 contributes some uncertainty, the detection of 9 feet and 10 feet of free product in 2008
and 2012 is more likely associated with periods of inactivity with respect to product recovery,
than new releases or groundwater table elevation trends. The trends in groundwater table
elevation and free product thickness at monitoring well B-3 and the nearby recovery well RW-6
are depicted in Figure 12. Total BTEX trends at RW-6 since 1993 demonstrate a spike in
concentration in 1995 groundwater samples accompanied by a 2-fold increase in BTEX ratio,
suggesting the occurrence of a new release of oil some time prior to 1995.
The free product present in wells B-5 and RW-6 is dyed red. The initial release of kerosene
reported in 1987 occurred prior to the requirement for dyeing off-road diesel fuel (1993-1994)
and kerosene (1999).
Evidence for additional releases of diesel fuel from the 4,000 gallon UST exist based on a 2001
tank testing report that showed the tank to have failed an ullage test. A July 2001 tank testing
report indicated that the 4,000 gallon diesel fuel UST and two (2) 10,000 gallon gasoline USTs
failed vacuum ullage testing on July 6, 2001. The tank report indicated that pressure could not
be sustained on the diesel fuel UST and a helium tracer test was performed documenting its
presence in surficial soil gas. Following repairs to the UST systems (replacement of gasoline
UST caps and unknown repairs on the diesel UST), all tanks, lines and leak detectors passed
re-testing on July 24, 2001. Tank testing results are included in Appendix C.
The forensic analysis of LNAPL samples collected from B-5 and RW-6 by Arcadis on May 5,
2009, and analyzed by Alpha Analytical Laboratories of Westborough, MA, revealed that both
samples were consistent with the heavier weight diesel fuel compounds and not representative
1 Free product gauging data was not available for review for the period from 1999 to 2008, which
coincides with the period when the product recovery system was in place but reportedly not operating
based on reports by others. During this time period, the recovery pump at RW-6 was likely left in place and thereby prevented well gauging.

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of the lighter weight kerosene compounds. Both sample chromatograms were indicative of a
single product.
The B-5 sample had a greater degree of weathering compared to the RW-6 sample based on n-
alkane/unresolved complex mixture peak height ratios of 3.33 and 6.07, respectively; fresh
diesel fuel is represented by ratio of 6.25, and n-C17/pristine and n-C18/phytane ratios of 1.18
and 1.4 for B-5 and 2.6 and 2.4 for RW-6, respectively; fresh diesel fuel is typically represented
by ratios around 2.5 (see Appendix D for analytical results and data summary by APEX
(October 22, 2010).
According to the current site owner, non-dyed K-1 kerosene and diesel fuel are sold at the site
containing <400 ppm and <15 ppm of sulfur, respectively. ENVIRON dispensed small amounts
of kerosene and diesel fuel from the respective fuel dispensers at the site, which confirmed the
presence of colorless kerosene and slightly greenish diesel fuel. The analysis of free product
samples collected from B-5 (former kerosene UST grave) and RW-6 (south of B-5 and the
current kerosene and diesel fuel USTs) for sulfur via ASTM Method D-4294 (collected by Apex
Company, LLC in June 2011), detected the presence of 407 ppm and 541 ppm of sulfur,
respectively.
US EPA regulations required that all diesel fuel failing to meet the low sulfur on-road
requirements be dyed red to distinguish it from fuel meeting on-road sulfur limits. Dyeing of
diesel began upon the introduction of these regulations on October 1, 1993. The Internal
Revenue Service (IRS) regulations, enacted as part of the Omnibus Budget Reconciliation Act
of 1993 and put into effect on January 1, 1994, placed similar dyeing requirements on diesel
fuel. In July, 1999, President Clinton, by Executive Order, required that all fuels (inclusive of
kerosene) intended for non-taxable off-road usage be dyed red.
Ultra low sulfur diesel (ULSD) fuel, containing <15 ppm of sulfur, was phased in from 2006 to
December 1, 2010. In 2007, off-road diesel fuel was required to contain less than 500 ppm
sulfur, and in 2010 all diesel was to be ULSD.
Based on the above information, an additional release of diesel fuel and possibly kerosene
occurred following the release of kerosene reported in 1987 given that the kerosene product
released at that time would not have been dyed red. An additional release of diesel fuel may
have occurred from the 4,000 gallon UST between 1993-1994 when red dye was first instituted
and the 2001 tank testing that indicated the diesel tank had failed ullage testing.
During a free product recovery event on November 5, 2012, ENVIRON noted that a vehicle had
hit the south-westernmost gasoline fuel dispenser and canopy support pole on the evening of
November 4, 2012. Site personnel indicated that the emergency shutoff system effectively
prevented a significant release of product. ENVIRON observed the presence of absorbent
material on pavement next to wells B-3 and RW-5 (see photographs). Free product was not
detected by ENVIRON in these wells via inspection with an interface probe.

Site Assessment Report and Modified CAP June 2015
Winston-Salem, NC
14
2.5 Drinking Water Well Inventory
According to the 1997 Catlin report, a survey of drinking water wells revealed the absence of
wells within a radius of 1,500 feet of the site except for six residential properties located off of
Lasley Drive south of the site. These wells are located crossgradient to the site with respect to
groundwater flow direction. ENVIRON determined through a site visit that four of the six
properties identified by Catlin are undeveloped.
ENVIRON conducted a comprehensive evaluation of drinking water wells located within one
1,500 foot radius of the site. An interview with James George of the Winston Salem Engineering
Department was initially conducted to determine if a listing of active wells was maintained. Mr.
George indicated there was no such listing. He stated that municipal water service was provided
throughout Lasley Drive at the time of the construction of the residential development on Wanda
Way located south of the site, during the period from 2000 to 2003. While Mr. George provided
water service plans for this area, he could not confirm whether or not residences chose to
connect to the municipal water system.
A visual inspection by ENVIRON was conducted on October 2, 2012, in an attempt to view
and/or speak with residents located south of the site concerning the status of their water supply.
Since the majority of the residential properties were fenced in with guard dogs and no
trespassing signs, interviews with property owners were not performed. Several concrete
drinking water well heads were observed at several locations; it could not be ascertained if the
wells were abandoned, active or not currently in use.
ENVIRON reviewed on-line Tax Assessor property cards for the subject area, which provide
utility information with respect to drinking water source. Since not all of the property cards
contained drinking water supply details, ENVIRON cross referenced city water utility billing
records to determine which residents were paying for city water service. Information obtained
from the drinking water well research is summarized in Table 6. A total of eight properties were
identified as not having paid water bills and as such are considered to currently rely on private
wells for potable water. These properties are located 125 to 300 feet west; 880 to 1,200 feet
southwest; and 665 to 1,200 feet south of the site (see Figure 13).
Tax Assessor records show that the current operator of the Three Boys CITGO business, Ziad
Wakim, is the current owner of the former Save & Go property located at 4980 Old Walkertown
Road. ENVIRON observed a drinking water well on this property (approximately 125 feet from
the site), as well as on the adjacent commercial property to the north at 4700 Davis Road. The
latter property was reported to be serviced by municipal water but the well head looked as
though it had not been properly abandoned.

3 CONCEPTUAL SITE MODEL
A conceptual site model concerning the release, migration and accumulation of kerosene and
likely diesel fuel in groundwater monitoring and recovery wells was developed to explain the
pathways taken following the release of product. This information is important to the
development of effective remedial actions direct at the recovery of free phase product.
Site Assessment Report and Modified CAP June 2015
Winston-Salem, NC
15
Free phase oil was first detected in October 1987 in a monitoring well (B-5) installed (May 29,
1987) in the center of the grave of the former kerosene UST, which was reportedly removed
sometime prior to May 1987 (CAP Addendum by Catlin Engineers and Scientists dated
February 20, 1998). Free phase oil was subsequently detected in a recovery well (RW-6)
installed (July 7, 1992) immediately south of the former kerosene tank grave. ENVIRON has not
observed free product in any other site wells since October 2012.
Oil released from the former kerosene UST and/or the existing kerosene and diesel fuel USTs
would have first encountered the permeable sand backfill of the tank grave, migrating further
under the pressure head established by the tank volume and the influence of gravitational
forces. Soil pores below the tank(s) became saturated with oil as it encountered the less
permeable native saprolite soils located at a depth of approximately 10 feet below ground
surface (bgs)2. The lateral extent of free product, at least initially, was confined to the porous
backfill beneath the kerosene and diesel fuel USTs that was confined by the native saprolite soil
within an area of approximately 400 square feet (i.e. Zone 1).
The accumulation of free product at the limit of Zone 1 likely created a secondary pressure head
that served to enhance the further downward migration of free phase oil into preferential
pathways provided by the network of interconnecting fractures within saprolite soil. While not all
fractures are likely to extend into the groundwater table, a sufficient number are expected to
extend through at least 13 feet of vadose zone soil until encountering the seasonal high
groundwater table located approximately 23 feet bgs (i.e. Zone 2).
The seasonal wet groundwater table at the 23-foot depth limit of Zone 2 likely attenuated the
vertical migration of free phase oil resulting in the lateral migration of free product via saprolite
fractures resulting in the expansion of the free product plume area. This area is estimated to be
approximately 700 square feet based on the proximity of B-5 and RW-6 and absence of free
product in nearby wells.
The accumulation of free product at the limit of Zone 2 likely created a tertiary pressure head
that served to enhance the further downward migration of free phase oil into preferential
interconnecting fractures within saprolite soil until reaching the seasonal low groundwater table
elevation of approximately 30 feet (i.e. Zone 3).
The bore hole and/or well annulus of B-5 and RW-6 are considered to serve as additional
preferential migration pathways for oil entering site groundwater.
The amount of oil adsorbed by silt/clay soils outside of saprolite fracture pores, is not
considered to be significant given the limited infiltration potential of these poorly permeable
soils, where the saturation of the first few inches of pore space likely serves as a barrier to oil
uptake further into the silt/clay matrix.
The considerable difference in free product thickness at B-5 and RW-6, measured by ENVIRON
in October 2012, is attributed to well construction differences where the well screens for
2 The 10 foot depth of the saprolite soil beneath the kerosene and diesel fuel USTs is based on the 64-inch
diameter of a 4,000 gallon UST and the soil boring log for B-5 (Appendix D).
Site Assessment Report and Modified CAP June 2015
Winston-Salem, NC
16
monitoring well B-5 and recovery well RW-6 were installed from 16 to 36 feet bgs and 30 feet to
50 feet bgs, respectively. Table 1 summarizes well construction details and soil boring logs are
presented in Appendix E. The detection of as much as 10 feet of oil at RW-6 is considered to
be due to a pressure gradient established by a pool of free phase oil at the limit of Zone 2
defined by the seasonal high groundwater table (approximately 23 feet bgs). Oil migrating
further down the annulus of RW-6 would enter the well screen at the 30 foot depth resulting in
the rise of oil within the solid wall riser-pipe portion of RW-6 until the level of the pool of oil
outside the well was reached. A pictorial representation of the CSM for the migration of oil into
the groundwater table at the site is presented as Figure 14.
The greater product thicknesses measured in October 2012 are considered to be influenced by
the period of inactivity of environmental assessment actions at the site, as well as being
indirectly related to groundwater table elevation, where the occurrence of free product was
observed to be greatest during seasonal dry periods. Given that the well screen at B-5 spans
the groundwater table, the free product thickness at this well, which ranged from 0.03 and 0.54
feet (average of 0.26 feet) between October 2012 and April 2015, is considered to be more
representative of free product thickness at the groundwater table than that measured at RW-6.
The free product at RW-6, which ranged from 0.01 feet and 3.68 feet (average of 0.89 feet),
however, is indicative of the persistence of free product entering B-5 and RW-6.
A total of approximately 31 gallons of oil was recovered via hand bailing events performed by
ENVIRON from October 2, 2012 to April 23, 2015. Groundwater gauging and free product hand-
bailing measurements are summarized in Table 7, with trends in free product thickness and
groundwater table elevations depicted in Figure 5.
3.1 Site Environmental Conditions
The majority of the site is covered by asphalt pavement, concrete dispenser and UST pads and
the 2,000 square foot site building. Surficial site soils consist of reddish silt/clay saprolite. While
saprolite’s typically have high porosities and relatively low permeability’s, mineralized veins in
the saprolite can serve as preferential channels for infiltrating precipitation and free product
releases. Bedrock was not encountered to a maximum assessment depth of 62 feet based on
previous investigations by others. The site is located in the Milton Belt of the Piedmont Province
where typical bedrock formations include biotite gneiss and schist rich in potassic feldspar and
garnets. The crystalline bedrock is the primary groundwater source in the Piedmont Province
where porosities are extremely low with highest permeability’s in fractures and fissures within
the rock.
Groundwater flow direction was determined to occur in an easterly direction in the western
portion of the site trending to a southeasterly direction in the central and eastern portions of the
site. Depth to groundwater ranges from 24 feet in the northwest corner of the site to 30 feet in
the southeastern portion of the site. Based on the depth to groundwater and tight unsaturated
saprolite soils, conditions were not considered to be favorable for vapor intrusion into the site’s
slab on grade convenience store.

Site Assessment Report and Modified CAP June 2015
Winston-Salem, NC
17
3.2 Extent of Contamination
While the detection of free phase gasoline and kerosene was previously reported in several site
wells, free product is currently limited to the 2-inch diameter PVC monitoring well installed in the
former kerosene tank grave (B-5) and the 2-inch diameter PVC recovery well RW-6 located
approximately 13 feet south of B-5. ENVIRON has not observed gasoline free product at the
site.
Based on the CSM developed for this site, three zones are considered to contain free phase oil:
Zone 1 - base of the tank grave at approximately the 9-10 foot depth; Zone 2 -seasonal high
groundwater table at approximately the 23-24 foot depth; and Zone 3 - seasonal low
groundwater table at approximately the 30-31 foot depth. The total pore volume in areas of
Zones 1, 2 and 3 considered to have the potential for mobile and/or technically recoverable free
phase oil is estimated to be 2,400 gallons based on calculations presented in the Corrective
Action Plan (CAP) in Appendix F.
3.3 Human and Ecological Receptors
The site property is abutted to the east by the Amina Café (5008 Old Walkertown Road) with My
School Too Day Care (5016 Old Walkertown Road) located further east on the north side of Old
Walkertown Road. A grass field, which abuts the site property to the north, is owned by the
Winston Salem/Forsyth County Board of Education and serves as an entry to the Ibraham
Elementary School grounds located approximately 1,100 feet northeast of the site. A club house
and pavilion owned by Compliment Civic Club of White Rock, Inc. are located further north.
Residential development is located further north and northwest along Davis Road.
Davis Road abuts the site to the west, beyond which is commercial development including a
former Save & Go convenience store located at 4980 Old Walkertown Road and a hair salon
that abuts the former Save & Go property to the north at 4700 David Road. Residential
development is located further west along Old Walkertown Road approximately 300 feet from
the site.
Old Walkertown Road abuts the site to the south, immediately beyond which is a N&W Railway
Company right-of-way and a residential community located approximately 300 to 550 feet south
of the site that was constructed on Wanda Way in the early 2000s. A large asphalt paved lot is
located approximately 180 feet southeast of the site with a warehouse located approximately
1,300 feet from the site at the east end of this property. This railroad property is reportedly used
for the loading/offloading of vehicles onto and from rail cars. Older residential neighbour hoods
are located further south and southeast within 1,500 feet of the site along Lasley Drive to the
south and Lampan Lane and Northwoods Circle to the southeast.
The closest ecological receptor is Jones Pond, a 0.4 acre pond located approximately 2,000
feet to the northwest of the site. A first order tributary (Brushy Fork) is located approximately
3,300 feet southeast of the site, and Salem Lake is located approximately 4.25 miles south of
the site.

Site Assessment Report and Modified CAP June 2015
Winston-Salem, NC
18
4 CONCLUSIONS
ENVIRON presents the following conclusions based on a review of previous reports by others
and environmental investigations conducted by ENVIRON at the site:
• ENVIRON initially detected the presence of red-dyed oil in a 2-inch diameter PVC
monitoring well (0.98 feet at B-5) located in the center of a former kerosene UST removed
circa 1987, and a 2-inch diameter PVC recovery well (10.34 feet at RW-6) located
immediately south of the UST grave during well gauging events in October 2012. These
wells are also located in close proximity of existing kerosene and diesel fuel USTs located
immediately east and west of the former kerosene UST. Free product was not observed in
any other site wells.
• ENVIRON performed weekly to monthly well gauging and free product hand bailing at the
site since October 2012; the frequency was commensurate with free product thickness,
which was shown to be indirectly related to groundwater table elevation. A total of
approximately 31 gallons of oil was recovered via hand bailing from October 2 to April 23,
2015. The product previously collected by others and stored in the 275 gallon AST located
within the locked remedial fence enclosure was properly disposed of by A&D Environmental
Services, Inc. in April 2013, along with the oil and water recovered by hand bailing of free
product at B-5 and RW-6, and the impacted purge water collected during the October 2012
groundwater sampling event. Approximately 70 gallons of oil and water remain on site in 55
gallon drums. Disposal of the full drum is being scheduled.
• Free product thickness measured after the initial October 2012 gauging events at B-5 and
RW-6, ranged between 0.03 and 0.54 feet (average of 0.26 feet) and 0.01 and 3.68 feet
(average of 0.89 feet), respectively. Given that the well screen at B-5 spans the groundwater
table, the free product thickness at this well is considered to be more representative of free
product thickness at the groundwater table than that measured at the recovery well RW-6
where the well screen is set from 30 feet to 50 feet bgs.
• The presence of as much as 10 feet of oil in RW-6 is considered to be due to a pressure
gradient established by the presence of free phase oil at the seasonal wet groundwater
table (approximately 20 feet bgs) and the contiguous and persistent occurrence of oil flowing
downward along the annulus of RW-6 and into the well at the 30 foot depth (top of the well
screen) resulting in the rise of oil approximately 10 feet within the solid wall riser-pipe portion
of RW-6. The amount of free product at RW-6, however, is indicative of the volume and
persistence of free product entering B-5 and RW-6.
• Based on the CSM developed for the migration and presence of free phase oil at the site,
three zones exhibiting the presence of mobile and/or recoverable oil were identified beneath
the existing kerosene and diesel fuel USTs: Zone 1 - base of the tank grave at
approximately the 9-10 foot depth; Zone 2 -seasonal high groundwater table at
approximately the 23-24 foot depth; and Zone 3 - seasonal low groundwater table at
approximately the 30-31 foot depth. The total pore volume within Zones 1, 2 and 3 with the
potential for mobile and/or technically recoverable free phase oil is estimated to be 2,400
gallons, which includes 670 gallons representing oil within saprolite fractures and 4,300
gallons representing potential leachable oil in/on silt and clay soil outside of the fractures.
Site Assessment Report and Modified CAP June 2015
Winston-Salem, NC
19
• Groundwater flow direction was determined to occur in an easterly direction in the western
portion of the site trending to a southeasterly direction in the central and eastern portions of
the site. Depth to groundwater ranged from 24 feet in the northwest corner of the site to 30
feet in the southeastern portion of the site.
• The laboratory analysis of groundwater samples for volatile petroleum hydrocarbon (VPH)
and extractable petroleum hydrocarbon (EPH) fractions and target analytes provided
information that was used to define three separate dissolved phase contaminant plumes;
one originating from the kerosene and diesel fuel UST area; one from the gasoline fuel
dispenser area; and one from the former gasoline UST area. All three plumes were shown
to extend in a southeasterly direction beneath Old Walkertown Road and a railroad right-of-
way south of the site.
• A large asphalt parking lot used by the railroad for the loading and unloading of vehicles is
located southeast of the site. No drinking water wells are located southeast and
downgradient with respect to groundwater flow within 1,500 feet of the site. While a
municipal drinking water system exists throughout the subject area, a total of eight
properties located within 125 to 1,200 feet west and south of the site either rely on private
wells for potable water or have wells that have not been properly abandoned.
• A review of tank testing records, forensic fingerprint analysis of free product, presence of
red-dyed free phase oil, and a forensic assessment of the degree of weathered dissolved
phase petroleum compounds revealed information supporting the occurrence of additional
releases of diesel fuel and gasoline at the site since that reported in the 1980s. The absence
of the detection of ethanol in groundwater samples collected at the site in October 2012,
negative tank and line testing results in 2012 and the limited extent of the free product
plume suggests that tank system releases are not ongoing.
• Given that dissolved phase contaminant plumes are not migrating towards human or
ecological receptors and that evidence supporting ongoing releases of petroleum products
has not been obtained, implementation of active remedial technologies to address dissolved
phase contaminants in groundwater is likely to be both exceedingly expensive and an
inefficient means of achieving additional reduction in residual contaminant concentrations
above that expected to occur from natural attenuation mechanisms alone.

Site Assessment Report and Modified CAP June 2015
Winston-Salem, NC
20
5 RECOMMENDATIONS
• ENVIRON proposes the recovery and reduction of free phase oil to less than 1/8 inch in site
wells as the primary remedial closure strategy for the site. The current site owner has
agreed to the removal of the existing kerosene and diesel fuel USTs, which will permit
access to the excavation of oil impacted tank grave soils to a depth of approximately 20 feet.
Extraction and inject wells shall be installed following backfilling and compaction of the
excavation grave with clean fill. A combination of high vacuum extraction of free
product/groundwater within and downgradient of the free product plume area enhanced by
surfactant injections shall be used to reduce free product to < 1/8 inch. Details concerning
the preferred remedial alternative are presented in a modified Corrective Action Plan in
Appendix F.
• Once free product has been reduced below 1/8 inch in site wells, the high risk ranking
applied to the site should be downgraded to low risk given that no drinking water wells are
located within 1,500 feet of the site in the direction of dissolved phase oil and/or gasoline
plumes.
• Well head protective boxes exhibiting damaged concrete collars and/or insecure lids should
be repaired to minimize the potential for surface runoff entering the well box and flooding the
well heads.
• Areas of cracked concrete fuel dispenser and UST pads should be repaired by the site
owner to minimize the potential for the entry of petroleum products from surface spills.
• Bollards should be installed by the site owner in areas of the fuel dispensers exposed to
vehicular traffic as a preventative means to minimize the potential for additional product
releases resulting from vehicle accidents like the one observed at the site on November 5,
2012 that damaged the southwestern most gasoline fuel dispenser and canopy support
pole.

Site Assessment Report and Modified CAP May 2015
Winston-Salem, NC

Figures

SITESITESITESITESITESITESITESITESITE
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SOURCE:
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DRAFTED BY:DATE:KPM 11/5/2012
SITE LOCATION MAP
FORMER GANT STATION #31
WINSTON-SALEM, NC
FIGURE
1
3330865A
OLD WALKE
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CONCRETE
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UNDER
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# 31
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CURRENT
GAS UST
AREA
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KEROSENE UST
REMEDIATION EQUIPMENT AREA
FORMER
KEROSENE
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DIESEL
FUEL UST
B-7 B-8
RW-12
RW/SV-11
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RW/SV-1
RW-2
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B-13
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B-15
B-2
B-5
RW/SV-6
B-4
B-6
B-1
RW/SV-5
B-16
SB-02/IJ-2
SB-01/IJ-1
B-12
B-14
B-17
B-18
B-19
B-18
B-9B-3
0
SCALE IN FEET
40
LEGEND
PROPERTY BOUNDARY
(APPROXIMATE)
FENCE
FORMER UST
MONITORING WELL
DEEP MONITORING WELL
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EXTRACTION LOCATION
RECOVERY WELL
LOCATION
SOIL BORING/INJECTION
WELL
DESTROYED WELL
DRAFTED BY:DATE:KPM 11/5/2012
SITE LAYOUT
FORMER GANT STATION #31
WINSTON-SALEM, NC
FIGURE
3330865A
2
SOURCE:
1.Google EarthTM MAPPING SERVICE
2.AET Site Plan from 2/11/11 Report
by AET on behalf of Exprezit!X
OLD WALKE
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R
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UNDER
CANOPIES
GANT
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AREA
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FUEL UST
61.88
68.29
68.55
68.77
69.01
69.58
69.81
69.95
69.97
70.24
70.48
70.77
70.90
70.90
70.96
70.98
71.05
71.10
71.14
71.16
71.21
71.29 68.570.070.571.070.10
70.44
69.069.15
69.5B-7 B-8
RW-12
RW/SV-11
RW-10
RW/SV-9
RW/SV-8 RW-7
RW/SV-1
RW-2
RW/SV-13
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B-13
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B-2
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SB-02/IJ-2
SB-01/IJ-1
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B-9B-3
0
SCALE IN FEET
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LEGEND
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FENCE
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DEEP MONITORING WELL
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EXTRACTION LOCATION
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SOIL BORING/INJECTION
WELL
DESTROYED WELL
GROUNDWATER
ELEVATION CONTOUR
(OCTOBER 2012)
DRAFTED BY:DATE:KPM 11/5/2012
OCTOBER 11, 2012 GROUNDWATER ELEVATION CONTOURS
FORMER GANT STATION #31
WINSTON-SALEM, NC
FIGURE
3330865A
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70.0SOURCE:
1.Google EarthTM MAPPING SERVICE
2.AET Site Plan from 2/11/11 Report
by AET on behalf of Exprezit!X
OLD WALKE
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CONCRETE
PAVED AREAS
UNDER
CANOPIES
GANT
STATION
# 31
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GAS UST
AREA
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FORMER
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UST
AMINA CAFE
DIESEL
FUEL UST71.070.75
70.92
71.08
71.13
71.21 70.95
69.89
68.91
70.22
68.7169.08
71.20
70.17
68.20
68.50
68.76
69.94
71.24
69.51
70.570.069.568.569.0
B-7 B-8
RW-12
RW/SV-11
RW-10
RW/SV-9
RW/SV-8 RW-7
RW/SV-1
RW-2
RW/SV-13
RW/SV-3
B-13
RW/SV-4
B-15
B-2
B-5
RW/SV-6
B-4
B-6
B-1
RW/SV-5
B-16
SB-02/IJ-2
SB-01/IJ-1
B-12
B-14
B-17
B-18
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B-18
B-9B-3
70.45
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LEGEND
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(APPROXIMATE)
FENCE
FORMER UST
MONITORING WELL
DEEP MONITORING WELL
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EXTRACTION LOCATION
RECOVERY WELL
LOCATION
SOIL BORING/INJECTION
WELL
DESTROYED WELL
GROUNDWATER
ELEVATION CONTOUR
(OCTOBER 22, 2012)
DRAFTED BY:DATE:KPM 11/5/2012
OCTOBER 22, 2012 GROUNDWATER ELEVATION CONTOURS
FORMER GANT STATION #31
WINSTON-SALEM, NC
FIGURE
3330865A
4
70.0SOURCE:
1.Google EarthTM MAPPING SERVICE
2.AET Site Plan from 2/11/11 Report
by AET on behalf of Exprezit!X
FIGURE
3330865ADATE:5.26.15
LNAPL Thickness, Cumulative LNAPL Recovery and
Adjusted Groundwater Table Elevation Trends at B-5 and RW-6 5
OLD WALKE
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AMINA CAFE
DIESEL
FUEL UST
21
19000
0.97J
300
B-7 B-8
RW-12
RW/SV-11
RW-10
RW/SV-9
RW/SV-8 RW-7
RW/SV-1
RW-2
RW/SV-13
RW/SV-3
B-13
RW/SV-4
B-15
B-2
B-5
RW/SV-6
B-4
B-6
B-1
RW/SV-5
B-16
SB-02/IJ-2
SB-01/IJ-1
B-12
B-14
B-17
B-18
B-19
B-18
B-9B-3
78
790
19
71.070.570.069.568.569.0
1
190
2.7
<2
<1
180
5300 1
5
,
0
0
0
1
,
0
0
0
79
1
0
0
5,00
0
0
SCALE IN FEET
40
LEGEND
PROPERTY BOUNDARY
(APPROXIMATE)
FENCE
FORMER UST
MONITORING WELL
DEEP MONITORING WELL
RECOVERY/VAPOR WELL
EXTRACTION LOCATION
RECOVERY WELL
LOCATION
SOIL BORING/INJECTION
WELL
DESTROYED WELL
ISOCONCENTRATION
&217285—J/'$6+('
WHERE INFERRED)
GROUNDWATER
ELEVATION CONTOUR
(OCTOBER 22, 2012)
DRAFTED BY:DATE:KPM 11/11/2012
07%(,62&21&(175$7,210$3—J/)25
OCTOBER AND NOVEMBER 2012
FORMER GANT STATION #31
WINSTON-SALEM, NC
FIGURE
3330865A
6
100
SOURCE:
1.Google EarthTM MAPPING SERVICE
2.AET Site Plan from 2/11/11 Report
by AET on behalf of Exprezit!X70.0
OLD WALKE
R
T
O
W
N

R
O
A
DDAVIS ROADUST
VENT
PIPES
AIR
PUMP
SURFACE DRAIN
FORMER GAS
UST AREA
DISPENSERS
CONCRETE
PAVED AREAS
UNDER
CANOPIES
GANT
STATION
# 31
SIGN
CURRENT
GAS UST
AREA
DISPENSER
KEROSENE UST
REMEDIATION EQUIPMENT AREA
FORMER
KEROSENE
UST
AMINA CAFE
DIESEL
FUEL UST
<50
557
160
3300
B-7 B-8
RW-12
RW/SV-11
RW-10
RW/SV-9
RW/SV-8 RW-7
RW/SV-1
RW-2
RW/SV-13
RW/SV-3
B-13
RW/SV-4
B-15
B-2
B-5
RW/SV-6
B-4
B-6
B-1
RW/SV-5
B-16
SB-02/IJ-2
SB-01/IJ-1
B-12
B-14
B-17
B-18
B-19
B-18
B-9B-3
71.070.570.069.568.569.0
35J
29J
2742
56.4
3910
11600 1517
664
7944
1,
0
0
0
2
,
0
0
0
5
,
0
0
0
10,0
0
0
15100
114000
1
0
0
,
0
0
0
0
SCALE IN FEET
40
LEGEND
PROPERTY BOUNDARY
(APPROXIMATE)
FENCE
FORMER UST
MONITORING WELL
DEEP MONITORING WELL
RECOVERY/VAPOR WELL
EXTRACTION LOCATION
RECOVERY WELL
LOCATION
SOIL BORING/INJECTION
WELL
DESTROYED WELL
ISOCONCENTRATION
&217285—J/'$6+('
WHERE INFERRED)
GROUNDWATER
ELEVATION CONTOUR
(OCTOBER 22, 2012)
DRAFTED BY:DATE:KPM 11/12/2012
727$/93+)5$&7,21,62&21&(175$7,210$3—J/)25
OCTOBER AND NOVEMBER 2012
FORMER GANT STATION #31
WINSTON-SALEM, NC
FIGURE
3330865A
7
1,000
SOURCE:
1.Google EarthTM MAPPING SERVICE
2.AET Site Plan from 2/11/11 Report
by AET on behalf of Exprezit!X70.0
OLD WALKE
R
T
O
W
N

R
O
A
DDAVIS ROADUST
VENT
PIPES
AIR
PUMP
SURFACE DRAIN
FORMER GAS
UST AREA
DISPENSERS
CONCRETE
PAVED AREAS
UNDER
CANOPIES
GANT
STATION
# 31
SIGN
CURRENT
GAS UST
AREA
DISPENSER
KEROSENE UST
REMEDIATION EQUIPMENT AREA
FORMER
KEROSENE
UST
AMINA CAFE
DIESEL
FUEL UST
<100
89J
217
49J
140
B-7 B-8
RW-12
RW/SV-11
RW-10
RW/SV-9
RW/SV-8 RW-7
RW/SV-1
RW-2
RW/SV-13
RW/SV-3
B-13
RW/SV-4
B-15
B-2
B-5
RW/SV-6
B-4
B-6
B-1
RW/SV-5
B-16
SB-02/IJ-2
SB-01/IJ-1
B-12
B-14
B-17
B-18
B-19
B-18
B-9B-3
71.070.570.069.568.569.0
44J
46J
160
82J
550
240
991
750 50
0
1,000
100,000
300,000
126800
395000
0
SCALE IN FEET
40
LEGEND
PROPERTY BOUNDARY
(APPROXIMATE)
FENCE
FORMER UST
MONITORING WELL
DEEP MONITORING WELL
RECOVERY/VAPOR WELL
EXTRACTION LOCATION
RECOVERY WELL
LOCATION
SOIL BORING/INJECTION
WELL
DESTROYED WELL
ISOCONCENTRATION
&217285—J/'$6+('
WHERE INFERRED)
GROUNDWATER
ELEVATION CONTOUR
(OCTOBER 22, 2012)
DRAFTED BY:DATE:KPM 11/12/2012
727$/(3+)5$&7,21,62&21&(175$7,210$3—J/)25
OCTOBER AND NOVEMBER 2012
FORMER GANT STATION #31
WINSTON-SALEM, NC
FIGURE
3330865A
8
1,000
SOURCE:
1.Google EarthTM MAPPING SERVICE
2.AET Site Plan from 2/11/11 Report
by AET on behalf of Exprezit!X70.0
9

FIGURE

3330865A DATE:2.20.2013
11 Groundwater Table Elevation and Free Product Trends at B-3 and RW-6
Located Immediately South of the Kerosene and Diesel Fuel USTs

FIGURE

3330865A DATE:2.20.2013
Site Plan Depicting Properties With Active
or Non-Abandoned Drinking Water Wells Within 1,500 feet of Site
Active or Non-Abandoned Drinking Water Wells
12

FIGURE

3330865A DATE:2.20.2013
Conceptual Site Model for Secondary Sources and Migration of LNAPL
Through Saprolite Fractures into Groundwater Showing
Total EPH Fraction Concentrations in mg/l
Former Gant #31 Station, Winston Salem, NC
13
Zone 1
Zone 2
Zone 3
NT
0.994 mg/l
0.15 mg/l
0.046 mg/l 395 mg/l
NT 126 mg/l NT NT 126 mg/l
395 mg/l 0.046 mg/l

FIGURE

3330865A DATE:2.20.2013
Free Phase
Oil Plume
Kerosene
UST
Diesel
UST
Site Plan Depicting Estimated LNAPL Plume
Former Gant #31 Station
Winston Salem, North Carolina
14
RW-6
B-5 Dissolved Phase
Oil Plume

FIGURE

3330865A DATE:2.20.2013
Estimated Schedule of Work Tasks
TASKS DESCRIPTION TIME PERIOD in WEEKS TIME PERIOD IN MONTHS
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 5 6 7 8 9 10 11 12
1 GPR Survey and Utility Clearance
2 UST, Dispensers and Canopy Removal
3 Soil Excavation and Disposal
4 Backfill and Asphalt Paving of Tank Grave
5 Injection and Extraction Well Installations
6 Well Head Survey
7 LNAPL Recovery & 1st Surfactant Injection
8 LNAPL and Surfactant Extraction
9 LNAPL Gauging and GW Monitoring
10 LNAPL Recovery & 2nd Surfactant Injection
11 LNAPL Recovery & 3rd Surfactant Injection
12 Quarterly Status Reports
13 Final Summary Report
15
Site Assessment Report and Modified CAP May 2015
Winston-Salem, NC
ENVIRON

Tables

Appendix BReporting TablesTop-Bottom of screen depth (feet)Well Head Elevation (feet)at Install ENVIRON at Install 10.16.12 10.11.12 10.22.12 10.11.12 10.22.12B-1 2 no locking cover - screw only 3.18.87 37 31.15 17.4-31.4 96.73 25.96 25.98 70.77 70.75B-2 2 slight non petroleum odor 3.18.87 37 34.30 20.5-35.5 97.80 27.36 27.35 70.44 70.45B-3 2 weathered oil odor 3.18.87 42 38.90 24.1-36.1 98.76 27.8 27.84 70.96 70.92B-4 2 good cap - needs lock 3.18.87 37 34.40 19.6-34.6 97.21 26.11 26.13 71.10 71.08B-5 2 red free product = good plug - needs locking cover 5.29.87 45 32.55 16.1-36.1 98.32 27.84FP 27.87FP 70.48 70.45B-6 2 stand pipe - needs new cap/lock 5.29.87 40 30.60 15.0-30.0 99.58 28.42 28.45 71.16 71.13B-7 2 modified well head - 2" to 1" rusted metal cap damaged 5.29.87 40 33.75 14.3-34.3 98.33 27.12 27.12 71.21 71.21B-8 2 below metal plate SW of gas pumps - black widow/recluse spiders 5.29.87 45 36.68 17.4-37.4 99.17 28.19 28.22 70.98 70.95B-9 2 good cap - needs lock 5.28.87 45 38.80 19.4-39.4 99.10 29.15 29.21 69.95 69.89B-13 2 B-13 was converted to RW-2 in grass - needs cap 9.7.88 42 40.50 20-40 99.43 30.21 30.35 69.22 69.08B-15 2 rusted close - needs 5 sided wrench or sledge hammer 9.8.88 42 no access 20.0-40.0 no data no access no access no access no accessB-16 2 good cap - needs lock 9.13.88 42 38.35 18.6-38.6 94.47 24.23 24.25 70.24 70.22B-18 2 Initially plugged with can and filled with sand - cleared 10.4.88 62 58.30 55-60 no data no access 30.31 no access no dataRW/SV-1 2 RW (metal plate) and SV (sewer manhole) S of new USTs 7.7.92 50 46.80 29-49/16-26* 98.58 29.81 29.87 68.77 68.71RW-2 2 equipment not removable; converted from MW B-13 9.7.88 42 40.50 see B-13 99.43 30.28 30.35 69.15 69.08RW/SV-3 2 RW (metal plate) and SV (sewer manhole) SE of gas pumps - hi traffic 7.8.92 50 48.40 29-49/13-28* no data 29.72 30.12 no data no dataRW/SV-4 2 RW (metal plate) and Sparge point cover S of gas pumps 7.8.92 50 47.40 29-49/12-27* 99.43 28.53 28.75 70.90 70.68RW/SV-5 2 RW (metal plate)-grass and SV pt cover -asphalt SW of gas pumps - dry 7.9.92 50 48.48 30-50/11-26* 99.60 dry (SV) 28.4 (RW) dry SV pt 71.2RW/SV-6 2 red free product in RW and SV. SV max depth = 26.54 ft 7.9.92 50 47.80 30-50/11-26* 98.25 36.37 FP 28.08FP 61.88 70.17RW-7 2 5.5 ft deep manhole (MH) - 6" of water; converted from B-17 10.6.88 50 46.45 20-40 98.60 no access 28.75 no data 69.85RW/SV-8 2 2.5' deep MH - needs new well cap, water below well head 7.10.92 50 45.80 30-50/15-30* 97.95 29.66 29.75 68.29 68.20RW/SV-9 2 2.5 ' deep MH - MW w/ cap with rainwater level 4" < well head 7.10.92 50 31.10 30-50/15-30* 98.20 29.65 29.7 68.55 68.50RW-10 2 2.5 ' deep MH - no MW cap-rainwater entering well; conveted from MW B-10 9.8.88 42 35.00 20-40 98.28 28.47 29.52 69.81 68.76RW/SV-11 2 2.5 ' deep MH - MW w/ cap, moist sand - no standing water 7.10.92 50 48.80 30-50/15-30* 98.74 28.77 28.8 69.97 69.94RW-12 2 2.5' deep MH - no MW cap rainwater entering well: converted from MW B-19 10.6.88 42 37.65 20-40 97.89 26.6 26.65 71.29 71.24RW/SV-13 2 gain access - gauge GW - high traffic 7.8.92 50 43.10 29-49/15-30* 98.71 29.13 29.2 69.58 69.51IJ-1 1 1" dia well - good cap and cover 10.2.07 35 no data 20-35 98.75 27.61 no data 71.14 no dataIJ-2 1 1" dia well - good cap and cover 10.2.07 30 no data 20-30 98.93 28.83 no data 70.10 no data* Depth range represents soil vapor extraction pointTable 1: Well Construction Iinformation and Survey DataMaximum Well Depth (feet)Installation DateNOTESWell Dia.Well ID #Depth to Groundwater (feet)Groundwater Table Elevation (feet)
Depth to
LNAPL DTW
Corrected
GW
Elevation
LNAPL
Thickness
Total
LNAPL
in
Bailers
Total
LNAPL
Recovered
Depth to
LNAPL DTW
Corrected
GW
Elevation
LNAPL
Thickness
Total
LNAPL
in
Bailers
Total LNAPL
Recovered
(feet)(feet)(feet)(feet)(feet)(gallons)(feet)(feet)(feet)(feet)(feet)(gallons)
10.2.12 25.81 26.5 72.32 0.73*3 0.276 26.98 27.96 70.36 0.98 1.19 0.11
10.11.12 26.03 36.4 70.46 10.34 87.2 8.022 27.30 27.84 70.48 0.54 ND ND
10.16.12 26.40 29.75 71.28 3.35 7.1 0.653 27.08 27.58 70.74 0.5 0.73 0.07
10.22.12 27.10 28.08 70.98 0.98 ND ND 27.37 27.87 70.45 0.5 ND ND
11.5.12 27.11 28.7 70.86 1.62 6 0.552 27.48 27.82 70.50 0.54 0.02 0.00
11.14.12 27.18 30.1 70.58 2.89 36.7 3.376 27.71 28.09 70.23 0.38 0.27 0.02
11.20.12 27.02 29.2 70.87 2.13 3.9 0.359 27.57 27.81 70.51 0.24 0.13 0.01
11.28.12 27.72 28.10 70.47 0.38 0.6 0.055 27.90 28.22 70.10 0.32 0.29 0.03
12.14.12 27.83 28.40 70.32 0.57 1 0.092 28.08 28.32 70.00 0.24 0.13 0.01
12.31.12 27.84 30.8 69.91 2.95 34.6 3.183 28.40 28.60 69.72 0.2 0.09 0.01
1.16.13 28.03 29.2 70.02 1.2 2 0.184 28.39 28.56 69.76 0.17 0.115 0.011
1.31.13 27.96 28.9 70.05 0.81 1.5 0.138 28.27 28.47 69.85 0.2 0.104 0.010
2.14.13 27.90 28.56 70.24 0.66 1.2 0.110 28.05 28.25 70.07 0.2 0.146 0.013
3.8.13 27.61 28.25 70.53 0.64 1 0.092 27.60 27.82 70.5 0.22 0.080 0.007
4.2.13 27.03 27.3 71.17 0.28 0.28 0.026 26.95 27.15 71.17 0.2 0.170 0.016
4.22.13 26.70 26.8 71.53 0.11 0.08 0.007 26.55 26.68 71.64 0.13 0.060 0.006
5.17.13 26.19 26.2 72.05 0.05 0.021 0.002 26.04 26.28 72.04 0.24 0.170 0.016
6.5.13 25.87 25.9 72.37 0.05 0.042 0.004 25.72 25.79 72.53 0.07 0.042 0.004
7.3.13 25.73 25.8 72.51 0.03 0.010 0.001 25.58 25.66 72.66 0.08 0.010 0.001
7.25.13 25.53 25.6 72.71 0.03 0.010 0.001 25.48 25.55 72.77 0.07 0.021 0.002
8.14.13 25.58 25.6 72.66 0.04 0.010 0.001 25.61 25.74 72.58 0.13 0.104 0.010
9.10.13 25.82 25.9 72.42 0.03 0.010 0.001 25.89 26.15 72.17 0.26 0.844 0.078
10.3.13 26.02 26.1 72.22 0.03 0.010 0.001 26.13 26.58 71.74 0.45 0.313 0.029
10.24.13 26.67 26.7 71.58 0.01 0.010 0.001 26.78 27.21 71.11 0.43 0.510 0.047
11.14.13 27.13 27.2 71.12 0.02 0.010 0.001 27.28 27.57 70.75 0.29 0.146 0.013
12.6.13 27.10 29.9 70.67 2.81 40.83 3.757 27.73 28.02 70.30 0.29 0.156 0.014
12.20.13 27.47 29.30 70.47 1.83 2.958 0.272 27.93 28.14 70.18 0.21 0.063 0.006
12.30.13 27.65 28 70.55 0.32 0.26 0.024 27.93 28.13 70.19 0.2 0.083 0.008
1.17/14 27.37 27.8 70.80 0.45 0.583 0.054 27.58 27.77 70.55 0.19 0.073 0.007
2.6.14 27.16 27.6 71.02 0.40 0.438 0.040 27.25 27.47 70.85 0.22 0.104 0.010
3.4.14 26.67 26.8 71.55 0.17 0.073 0.007 26.66 26.85 71.47 0.19 0.083 0.008
3.27.14 26.11 26.3 72.12 0.14 0.073 0.007 26.04 26.27 72.05 0.23 0.073 0.007
4.24.14 25.16 25.2 73.08 0.07 0.042 0.004 25.08 25.19 73.13 0.11 0.042 0.004
5.22.14 24.33 24.4 73.91 0.06 0.010 0.001 24.26 24.30 74.02 0.04 0.010 0.001
7.2.14 24.27 24.3 73.97 0.05 0.010 0.001 24.33 24.36 73.96 0.03 0.010 0.001
7.24.14 24.61 24.7 73.63 0.04 0.005 0.000 24.79 24.82 73.50 0.03 0.005 0.000
8.27.14 25.41 25.5 72.83 0.04 0.010 0.001 25.65 25.86 72.46 0.21 0.125 0.012
10.17.14 26.76 26.80 71.48 0.04 0.005 0.000 27.03 27.56 70.76 0.53 0.458 0.042
11.12.11 26.81 30.49 70.81 3.68 54.67 5.029 27.61 28.06 70.26 0.45 0.375 0.035
12.12.14 27.62 29.70 70.28 2.08 16.92 1.556 28.18 28.63 69.69 0.45 0.229 0.021
Table 2. LNAPL Thickness and Recovered Volume Measurements at RW-6 and B-5
RW-6 B-5
Date
12.30.14 28.15 29.96 69.79 1.81 11.83 1.089 28.62 29.07 69.25 0.45 0.146 0.013
1.22.15 28.39 29.56 69.66 1.17 6.02 0.554 28.75 29.12 69.20 0.37 0.240 0.022
2.27.15 28.14 29.60 69.86 1.46 10.67 0.981 28.65 28.88 69.44 0.23 0.146 0.013
3.27.15 27.72 29.32 70.26 1.6 2.70 0.248 28.17 28.38 69.94 0.21 0.104 0.010
4.23.15 27.72 28.97 70.32 1.25 1.73 0.159 27.93 28.2 70.12 0.27 0.073 0.007

30.92 0.76Total LNAPL Recovered (gallons)Total LNAPL Recovered (gallons)
10.16.2012 = bail down test limited volume of LNAPL recovered
11.12.2014 = LNAPL recovery was halted with approximately 1.5 feet remaining in RW-6
12.12.2014 = LNAPL recovery was halted with approximately 1.5 feet remaining in RW-6
LNAPL = light non-aqueous phase liquid ND = not determined DTW = depth to water
Corrected GW Table Elevation = Well head elevation - [DTW+(LNAPL thickness x 0.83)]
LNAPL recovered (gallons) per event = No# of feet of LNAPL measured in bailer(s) retrieved until FP thickness <1/8 to 1/4 inch
2 *0.73 foot value = product thickness in the Soil Vapor Extraction point at RW/SV-6, which had a maximum depth of
10.11.2012 = LNAPL recovery was halted with approximately 3 feet remaining in RW-6
Table 3. Groundwater Quality Data Collected at Equilibrium During Low Flow SamplingGant Oil Company3330865A5000 Old Walkertown Road, Winston Salem, NCTom Morrissey and Fred SteinePoint of Total Depth toStanding VolumeFlow Well ID Date Time Reference Depth Water Water Height Purged Odors pH Temp Sp. Cond. ORP D.O. TurbdityRateSampled (PVC/Rim) (feet) (feet) (feet) (gallons) (Y/N) (oC) uS/cm (mV) (mg/L) (NTU) (ml/min)B-4 10/23/201211:15 PVC 34.40 26.13 8.27 4.25 N5.0822.14 133 64 0.22 9.81 170B-5 10/24/201217:20 PVC 32.55 27.59 4.96 none FPB-8 10/23/201213:50 PVC 36.68 28.2 8.48 3.75 N5.5312.06 237 60.9 0.18 5.43 230B-16 10/23/201218:45 PVC 38.35 24.25 14.1 1.7 N 4.5 20.61 81 113 2.7 0.19154RW-1 10/23/201219:50 PVC 46.8 29.65 17.11 2.4 N 6.07 21.46 235 -55 0.16 4.5 190RW-3 10/23/201217:13 PVC 48.40 29.15 19.25 2.55 N 5.59 21.88 66 27 0.37 2.51 215RW-4 10/24/201216:45 PVC 47.40 28.45 18.95 2.75 N 5.97 21.68 169 48 0.22 2.59 255RW-5 10/23/201214:00 PVC 48.48 28.4 20.08 2.95 N 4.71 22.15 396 105 2.92 0.4 215RW-6 10/24/201217:55 PVC 47.80 27.1 20.70 none FPRW-8 10/24/201211:16 PVC 45.80 29.78 16.02 4.25 N 6.79 20.03 113 -60 0.17 9.19 190RW-11 10/24/201215:28 PVC 48.80 28.8 20 4.6 N 6.81 20.46 113 -83 0.43 9.37190RW-12 10/24/201212:25 PVC 36.85 26.65 10.2 15 N 4.91 20.14 102 263 1.47 9.52500RW-13 10/23/201219:50 PVC 43.10 29.08 14.02 2.3 N 6.44 21.48 267 71 0.4 3.58270RW-6 10/24/201217:55 PVC 47.80 27.1 20.70 none FPField Instrumentation I.D. Number Calibration NotesYSI Multimeter Interface probeGeosubmersible pumpNotes:Sample tubing placed 5 feet below groundwater table due to varying well depths of 30 to 50 feetDuplicate sample from RW‐3FP = free product0.27 feet of FP at time of sampling Client: Job Number:Location:Date:11.22,23 & 24. 2012Personnel: Weather:Sunny 80s F0.27 feet of FP at time of sampling0.27 feet of FP at time of sampling Final Readings
WELL IDSampling DateDepth (feet)ElevationReference ElevationC5-C8 AliphaticsC9-C12 AliphaticsC9-C10 AromaticsTotal VPHEthanolIsopropyl EtherMTBE Naphthalene Benzene Toluene Ethylbenzene o- Xylene p-m XyleneTotal XylenesTotal BTEX400 none none none 4000 70 20 6 1 600 600 none none 500 noneB-410.23.1226.13 71.08 97.21<5019 16 35<200 <.5 <10.5<.5 <.5 <.5 <.50.53 0.53 0.53B-510.24.1227.87 70.45 98.3242<502700 2742<400 <1.0 <2.078 4.3 12 15 57 51 108 139.3B-810.23.1228.22 70.95 99.17 7628560 664<20007.7 190 21<.5 <5 <5226.828.8 28.8B-1610.22.1224.25 70.22 94.47<50 <50 <50 <50 <200 <.521<1 <0.5 <0.5 <0.5 <0.5 <1 <1.0 0RW-110.23.1229.87 68.71 98.58 87 270 200 557<2000 <579 29<59.2 54 34 80 114 177.2RW-310.23.12460 57 1000 1517<100022 790 170 67 7.6 75 250 170 420 569.6RW-3Dup-01 48040 11001620<100024 860 160 75 8.1 84 280 190 470 637.110.23.12RW-410.23.1228.75 70.68 99.43 600<20011000 11600<10004.0 78 860 40 270 500 1700 2500 4200 5010RW-510.23.1228.40 71.20 99.629<50<9.4 29<200 <.52.7<1 <0.5 <0.5 <0.5 <0.5 <1 <1.0 <1.0RW-610.24.1228.08 70.17 98.25 410 1300 2200 3910<10006.50 19 190 66 190 120 310 430 740 1116RW-810.24.1229.75 68.20 97.95 7700 74 170 7944<2000340 19000 26 31 6.8<57.2<107.2 45RW-911.5.128100 3900 3100 15100<4,000560 5,300 590 4,500491,100810 2,0002810 8,459RW-1011.5.1291000 13000 10000 114000<4,000240180930 23000 44000 3300 5700 12000 17700 88000RW-1110.24.1228.80 69.94 98.742072 68 160<200 <.50.97 0.62<0.5 <0.50.99<0.50.7 0.71.69RW-1210.24.1226.65 71.24 97.89<3.1515.456.4<200 <.5 <1.0 <1.0 <0.5 <0.5 <0.5 <0.5 <1.0 <1.0 <1.0RW-13010.23.1229.20 69.51 98.71 2300 190 810 3300<200019 300 76 250 10 240 85 190 275 775NOTES:VPH = volatile petroleum hydrocarbons VOC = volatile organic compoundsTotal BTEX = summation of benzene, toluene, ethylbenzene and total xylene concentrationsMTBE = methyl tert butyl ether<200 = no detected above reportable detection limit; Italicized concentrations represent J values where levels detected are above MDLs but below the minimum laboratory reporting LimitsShaded values indicate concentrations exceeding applicable NCDENR StandardsBolded results indicate concentrations in excess of the laboratry reportale detection limitTable 4Groundwater Analytical Results - VPH Fractions via MassDEP Method and Target VOC Analytes and Ethanol via Method SM6200 B Results reported in Micrograms per Liter (ug/L)GroundwaterNCDENR GROUNDWATER STANDARDSVPH Fractions VOCs
WELL IDSampling DateDepth (feet)ElevationReference ElevationC9-C18 AliphaticsC19-C36 AliphaticsC11-C22 AromaticsTotal EPHNaphthalene2-methyl NaphthaleneAcenaphthene Fluorene Phenanthrene Anthracene Fluoranthene PyreneBenzo(a) AnthraceneChryseneBenzo(a) PyreneIndeno (1,2,3-cd) Pyrene700 10000 200* none 6 30 80 300 200 0.002 300 200 0.05 5 0.005 0.05B-410.23.1226.13 71.08 97.21<100 <10044 44<10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <100.00B-510.24.1227.87 70.45 98.32 45000 59000 22000 12600073230<100 <10029<100 <100 <100 <100 <100 <100 <100 98.32B-810.23.1228.22 70.95 99.17<100 <100150 150 139.9<10 <10 <10 <10 <10 <10 <10 <10 <10 <1099.17B-1610.22.1224.25 70.22 94.47<100 <100 <100 <100 <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <1094.47RW-110.23.1229.87 68.71 98.58<110 <11089 8916.02.70<10 <10 <10 <10 <10 <10 <10 <10 <10 <10 98.58RW-310.23.120.00<100 <100160 160 75.0 36<10 <10 <10 <10 <10 <10 <10 <10 <10 <100.00Dup-0110.23.12 <100 <100170 170 93.0 51<10 <10 <10 <10 <10 <10 <10 <10 <10 <10RW-410.23.1228.75 70.68 99.4341<100950 991 470 380<100 <100 <100 <100 <100 <100 <100 <100 <100 <10099.43RW-510.23.1228.40 71.20 99.6<100 <10046 46<10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 99.60RW-610.24.1228.08 70.17 98.25 240000 59000 96000 395000 210 71037110 200<100 <10036<100 <100 <100 <10098.25RW-810.24.1229.75 68.20 97.95<110 <11082 8211<10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <1097.95RW-911.5.12 <110 <110240 240 310 93<104.7<10 <10 <10 <10 <10 <10 <10 <10RW-1011.5.12 <100 <100550 550490.0120<102.6<10 <10 <10 <10 <10 <10 <10 <10RW-1110.24.1228.80 69.94 98.7457<110160 217<10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <1098.74RW-1210.24.1226.65 71.24 97.89<110 <11049 49<10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 <1097.89RW-1310.23.1229.20 69.51 98.71<100 <100140 140 58.0 11<10 <10 <10 <10 <10 <10 <10 <10 <10 <10 98.71NOTES:* Standard is C9-22EPH =extractable petroleum hydrocarbons PAH = polycyclic aromatic hydrocarbons<100 = Not detected above reportable detection limitItalicized concentrations represent J values where levels detected are above MDLs but below the minimum laboratory reporting LimitsShaded values indicate concentrations exceeding applicable NCDENR StandardsBolded results indicate concentrations in excess of the laboratory reportale detection limit Table 5NCDENR  GROUNDWATER STANDARDSEPH (ug/L)PAHs (ug/L)Groundwater Analytical Results - EPH Fractions via MassDEP Method and Target PAH Analytes via Method 625Results reported in Milligrams per Liter (mg/L) for EPH Fractions and Micrograms per Liter (ug/L) for Target PAH AnalytesGroundwater Table
City Water Well yes no
4700 Davis Road 180 W Commercial X X X
4706 Davis Road 300 NW Residence - X X
4710 Davis Road 360 NW Residence - X X
4814 Davis Road 800 NW Residence - X X
4820 Davis Road 920 NW Residence - X X
4818 Davis Road 1000 NW Residence - X X
4824 Davis Road 1100 NW Residence - X X
4776 White Rock Rd 1200 NW Residence - X X
4980 Old Walkertown 125 W Commercial X X X
4968 Old Walkertown 300 W Residence -X meter X
4900 Wanda Way 420 SW Residence - X X
4901 Wanda Way 550 SW Residence - X X X
4910 Wanda Way 370 SW Residence - X X
4911 Wanda Way 525 SW Residence - X X
4920 Wanda Way 320 SW Residence - X X
4921 Wanda Way 500 SW Residence - X X
4930 Wanda Way 300 S Residence -X X4931 Wanda Way 550 S Residence - X
4940 Wanda Way 240 SE Residence - X X
4941 Wanda way 550 SE Residence - X X
4950 Wanda way 360 SE Residence - X X
4951 Wanda Way 440 SE Residence - X X
4597 Lasley Drive 1280 SW Residence X X X
4601 Lasley Drive 1200 SW Residence X X X
4613 Nelsen St 1200 S Residence -XX
4617 Nelsen St 1200 S Residence -XX
4621 Nelsen St 1000 S Residence -XX
4623 Lasley Drive 950 SW Residence X X X
4628 Lasley Drive 950 SW Residence X X X
4633 Westmooreland 880 SW Residence - X X
4637 Lasley Drive 840 S Residence - X X
4645 Lasley Drive 645 S Residence - X
4659 Lasley Drive 665 S Residence X X
4943 Doris Street 730 SW Residence X (pvc) X X
Table 6. Summary of Drinking Water Well Information
Blue highlight represents probable location of active or abandoned drinking water wells
Street Address
Distance
from site
(feet)
Property
Type
Well Head
Observed1
Tax Assessor Property
Card Records
Water Utility Bill
Records
Not listed
Not listed
Not listed
1 Based on ENVIRON drive-by inspection conducted October 2, 2012