WS-10089_45242_CA_FPR_20221215

FREE PRODUCT RECOVERY REPORT

BFI 4
1506 HEADQUARTERS DRIVE
GREENSBORO, GUILFORD COUNTY, NC
GROUNDWATER INCIDENT: 45242
FACILITY ID: 00-0-0000009978

DECEMBER 15, 2022

UST/PROPERTY OWNER: Davenport Energy, Inc. P. O. Box 879 Chatham, VA 24531 Phone Number: [phone]
UST OPERATOR:
Abercrombie Oil Company, Inc.

CONSULTANT:
Paragon Environmental Consultants, Inc. P. O. Box 157 Thomasville, NC 27361-0157 Phone Number: [phone]

RELEASE INFORMATION:
Date Discovered: 6/13/19 Estimated Quantity of Release: Unknown
Cause of Release: Unknown Source of Release: USTs, Piping, and Dispensers
Size and Contents: Four (4) 4,000 Gallon Gasoline USTs
and Two (2) 4,000 Gallon Diesel USTs
Latitude: N 36.08417392o Longitude: W 79.76596523o

This Free Product Recovery Report for this site has been prepared by Paragon
Environmental Consultants, Inc. under the direct supervision of a licensed geologist. All
activities performed on this project were conducted under my direct supervision:

Benjamin W. Robinson, L.G. North Carolina License # 2466

December 15, 2022

Barry McKinney
Davenport Energy, Inc. P. O. Box 879 Chatham, VA 24531 Reference: Free Product Recovery Report BFI 4 1506 Headquarters Drive Greensboro, Guilford County, North Carolina Groundwater Incident # 45242 Facility ID #00-0-0000009978

Dear Mr. McKinney:

In accordance with an approved Task Authorization Form dated October 10, 2022,
contained herein is a Free Product Recovery Report for the release which occurred at the
above referenced facility. These activities have been conducted following the release of
petroleum which occurred in the vicinity of the underground storage tank (UST) system
formerly located at this site.
The field activities conducted at this facility consisted of the removal of free product and contaminated groundwater using AFVR from two recovery wells located at this facility. All activities were conducted in accordance with North Carolina Department of Environmental Quality (NCDEQ) guidelines and the requirements of 15A NCAC 2N. Mr. McKinney, if you have any questions regarding this report, please contact our office.
Sincerely,
Benjamin W. Robinson, L.G. Paragon Environmental Consultants, Inc.

R22-1939FP
PARAGON
Environmental Consultants, Inc.
P.O. Box 157 • Thomasville, NC 27361-0157
Business Ph: [phone] • Fax: [phone]

TABLE OF CONTENTS

Page

A. Title Page .................................................................................. i B. Site Status and Conclusions .................................................... 1 B.1 Introduction and Scope of Services ............................... 1 B.2 Free Product Thickness .................................................. 2 B.3 Conclusions .................................................................... 3 C. Figures
Figure 1: Project Location Map (U.S.G.S. Topographic Map) Figure 2: Site Layout and Monitor Well Locations

D. Tables

Table 1: Monitor Well Information and Groundwater Elevations

E. Appendices
Appendix A: AFVR Data Report (Prepared by Advanced Environmental) Appendix B: Well Construction Records Appendix C: Liquids Disposal Manifest

Page - 1
FREE PRODUCT RECOVERY REPORT BFI 4 1506 Headquarters Drive Greensboro, North Carolina

B. Site Status and Conclusions B.1 Introduction and Scope of Services

Davenport Energy, Inc. owns a facility at 1506 Headquarters Drive in Greensboro, NC, which is referred to as BFI 4. Figure 1 illustrates the location of the project site on a partial Greensboro Quadrangle U.S.G.S. topographic map. The subject property was operated as a fueling station by Abercrombie Oil Company until 2014. The USTs were removed from the site on June 13, 2019 by Petroserve, Inc. A sheen of free product was observed on the groundwater encountered in the tank pit at approximately 8 feet below surface grade. Petroleum odors were noted in the UST excavation. After removing the tanks, 860 gallons of groundwater and free product were recovered from the UST excavation on June 13, 2019, before backfilling the UST excavation. Figure 2 illustrates the site layout, monitor well locations, and the former locations of the USTs. A 20-Day Report was submitted to the NCDEQ by Paragon on July 2, 2019. An UST Closure Report was submitted to the NCDEQ by Paragon on July 18, 2019. An Initial Abatement Action Report for the project site was submitted to the NCDEQ by Paragon on September 12, 2019. A Limited Site Assessment (LSA) was submitted to the NCDEQ by Paragon on October 8, 2019. A Comprehensive Site Assessment (CSA) was submitted to the NCDEQ by Paragon on September 24, 2020. Free Product Recovery Reports were submitted to the NCDEQ by Paragon on June 15, 2021 and November 30, 2021. A Free Product Gauging Letter report was submitted to the NCDEQ by Paragon on September 30, 2022. A free product recovery event performed in accordance with a recently approved Task Authorization Form for this facility consisted of the following:

o Recovery of free product using AFVR by Advanced Environmental Services, Inc.
of Greensboro, North Carolina

o Free product gauging of two monitor wells following a period of five days after the
AFVR by Paragon

o Summary of free product removal activities

The free product recovery activities conducted at this site have included the recovery and
disposal of free product through Aggressive Fluid Vapor Recovery (AFVR). The AFVR
event was conducted in monitor wells MW-1 and MW-2 located near the release source.
The AFVR was conducted using these wells over a period of eight hours. All activities
were conducted in accordance with North Carolina Department of Environmental Quality
(NCDEQ) guidelines and the requirements of 15A NCAC 2N .0705.

Page - 2

B.2 Free Product Recovery

UST Closure, Letter Report, and CSA
A sheen of free product was observed on the groundwater encountered in the tank pit at approximately 8 feet below surface grade. Petroleum odors were noted in the UST excavation. After removing the tanks, 860 gallons of groundwater and free product were recovered from the UST excavation on June 13, 2019, before backfilling the UST excavation. Free product thicknesses of 1.27 feet in MW-1 and 0.49 feet in MW-2 were measured on March 25, 2020 during the surface water sampling activities conducted in Muddy Creek, approximately 115 feet south of the release area. Free product thicknesses of 1.49 feet in MW-1 and 0.55 feet in MW-2 were measured on June 11, 2020 during the CSA activities.
Aggressive Fluid Vapor Recovery (AFVR)
One eight-hour AFVR event has been performed on May 12, 2021 at the BFI 4. A total of 506 gallons of liquids were recovered during the AFVR event. Seven gallons of liquid free product were recovered, as well as an additional 16.07 gallons of volatized free product that were recovered in the vapor phase. Advanced Environmental Services, Inc. (Advanced) provided a vacuum trailer utilized for product recovery, as well as a tanker for temporary storage of the groundwater and free product removed from the monitor wells. The recovered liquids were transported by Zebra Environmental and Industrial Services, Inc. (Zebra) to their facility in High Point, North Carolina for disposal. The cost for the AFVR event completed in May of 2021 was approximately $67.28 per gallon of recovered product (including gasoline which was volatilized and not recovered as liquid).

Mobile Multi-Phase Extraction (MMPE)

One 96-hour MMPE event has been performed between October 18, 2021 and October 22,
2021 at the BFI 4. A total of 5,282 gallons of liquids were recovered during the MMPE
event. 18 gallons of liquid free product were recovered, as well as an additional 19.21
gallons of volatized free product that were recovered in the vapor phase. Advanced
provided a vacuum trailer utilized for product recovery, as well as a tanker for temporary
storage of the groundwater and free product removed from the monitor wells. The
recovered liquids were transported by Zebra to their facility in High Point, North Carolina
for disposal.
The NCDEQ has recommended MMPE for sites which contain significant quantities of free phase petroleum product on the groundwater table. MMPE was selected for this
recovery event due to the volume of free product which was present at the subject site. The
cost for the MMPE event completed in October of 2021 was approximately $218.90 per
gallon of recovered product (including gasoline which was volatilized and not recovered
as liquid). The total amount of gasoline product recovered to date from this facility by
MMPE is approximately 37.21 gallons.

Page - 3
Aggressive Fluid Vapor Recovery (AFVR)
One eight-hour AFVR event has been performed on November 16, 2022 at the BFI 4. A total of 832 gallons of liquids were recovered during the AFVR event. A sheen of liquid free product was present on the liquids that were recovered. Advanced provided a vacuum trailer utilized for product recovery, as well as a tanker for temporary storage of the groundwater and free product removed from the monitor wells. The recovered liquids were transported by Zebra to their facility in High Point, North Carolina for disposal. Appendix A contains a copy of the AFVR data report (prepared by Advanced). Appendix B contains a copy of the well construction records for the monitor wells utilized during this AFVR event. Appendix C contains a copy of the liquids disposal manifest for the recovered liquids. The NCDEQ has recommended AFVR for sites which contain minor quantities of free phase petroleum product on the groundwater table. AFVR was selected for this recovery event due to the volume of free product which was present at the subject site. The cost for the AFVR event completed in November of 2022 was approximately $2.34 per gallon of recovered liquids (including gasoline which was volatilized and not recovered as liquid). The total amount of gasoline product recovered to date from this facility by AFVR and MMPE is approximately 60.28 gallons. Table 1 contains the cumulative free product recovery results for the three free product recovery events conducted at the BFI 4.

Product Type, Thickness, and Rate of Return

No free product was detected in the monitor wells on November 16, 2022 immediately
prior to initiation of the AFVR event. The rate of recovery for the contaminated liquids
was calculated at 104 gallons per hour based on the total of 832 gallons of contaminated
liquids recovered over the eight-hour AFVR event.

After the completion of the AFVR event on November 16, 2022, free product
measurements were taken in the monitor wells used as extraction points. No free product
was detected in the monitor wells immediately following completion of the AFVR event.
The wells were also measured for free product following a period of five days at the BFI
4. No free product was detected in the monitor wells during the Free Product Level Check
conducted on November 21, 2022. Table 1 summarizes the monitor well information and
groundwater elevation data collected during the November 2022 AFVR activities at this
facility.

B.3 Conclusions
Free Product Recovery activities at the BFI 4 have been conducted. From a review of all information gathered during this project, Paragon Environmental Consultants, Inc. makes
the following conclusions:

o Approximately 832 gallons of contaminated groundwater (with a sheen of free product present in the storage tanker) were recovered during the eight-hour AFVR event performed on November 16, 2022.

o The contaminated groundwater which was recovered during the AFVR event were transported by Zebra to their facility in High Point, North Carolina for disposal.

Page - 4
Based upon a review of all information gathered during this project, Paragon Environmental Consultants, Inc. makes the following recommendations:

o A comprehensive sampling event should be conducted to obtain current groundwater contaminant concentration data. Groundwater contaminant concentrations at levels below the Gross Contaminant Levels (GCLs) would allow site closure via a Notice of Residual Petroleum.

o A copy of this report should be forwarded to the following address: Guilford County Health Department 400 W. Market Street – Suite 300 Greensboro, NC 27401

This report has been prepared for the exclusive use of Davenport Energy, Inc. for the specific application to the referenced site located in Guilford County, North Carolina. The evaluation was conducted based on the scope of work and level of effort desired by the client and with resources adequate only for the scope of work. Our findings have been developed in accordance with generally accepted standards for Free Product Recovery Reports in the State of North Carolina, available information, and our professional judgment. No other warranty is expressed or implied. The data presented in this report are indicative of conditions at the precise locations sampled and the time the sample was collected. Additionally, the data obtained from the samples would be interpreted as meaningful with respect to the parameters in the laboratory reports. No additional information can be logically inferred from this data.

FIGURES

TABLES

TABLE 2
Monitoring Well Information and Groundwater Elevations (5/12/21 AFVR)
BFI 4
Greensboro, North Carolina
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 6.85 7.87 1.02 92.13
MW-2 99.58 97.58 87.58 6.69 7.22 0.53 92.36
MW-3 99.90 95.90 85.90 N/A 6.60 N/A 93.30
MW-4 99.50 99.00 89.00 N/A 6.91 N/A 92.59
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A 7.23 N/A 92.69
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured before AFVR at 9:15 AM on May 12, 2021.
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 N/A 11.33 0.00 88.67
MW-2 99.58 97.58 87.58 N/A 11.59 0.00 87.99
MW-3 99.90 95.90 85.90 N/A 7.31 N/A 92.59
MW-4 99.50 99.00 89.00 N/A 7.18 N/A 92.32
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A 7.58 N/A 92.34
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured after AFVR at 5:15 PM on May 12, 2021.
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 7.25 7.54 0.29 92.46
MW-2 99.58 97.58 87.58 6.95 7.01 0.06 92.57
MW-3 99.90 95.90 85.90 N/A N/A N/A N/A
MW-4 99.50 99.00 89.00 N/A N/A N/A N/A
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A N/A N/A N/A
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured six days after AFVR on May 18, 2021.
X21-1939B
TABLE 2 (CONT'D)
Monitoring Well Information and Groundwater Elevations (10/18-22/21 MMPE)
BFI 4
Greensboro, North Carolina
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 7.38 8.10 0.72 91.90
MW-2 99.58 97.58 87.58 8.13 8.15 0.02 91.43
MW-3 99.90 95.90 85.90 N/A N/A N/A N/A
MW-4 99.50 99.00 89.00 N/A N/A N/A N/A
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A N/A N/A N/A
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured before MMPE at 10:30 AM on October 18, 2021.
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 N/A 10.12 0.00 89.88
MW-2 99.58 97.58 87.58 N/A 9.19 0.00 90.39
MW-3 99.90 95.90 85.90 N/A N/A N/A N/A
MW-4 99.50 99.00 89.00 N/A N/A N/A N/A
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A N/A N/A N/A
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured after MMPE at 10:30 AM on October 22, 2021.
X21-1939B
TABLE 2 (CONT'D)
Monitoring Well Information and Groundwater Elevations (11/16/22 AFVR)
BFI 4
Greensboro, North Carolina
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 N/A 7.18 0.00 92.82
MW-2 99.58 97.58 87.58 N/A 6.41 0.00 93.17
MW-3 99.90 95.90 85.90 N/A 7.11 N/A 92.79
MW-4 99.50 99.00 89.00 N/A 6.65 N/A 92.85
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A N/A N/A N/A
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured before AFVR at 8:15 AM on November 16, 2022.
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 N/A 11.03 0.00 88.97
MW-2 99.58 97.58 87.58 N/A 11.23 0.00 88.35
MW-3 99.90 95.90 85.90 N/A 7.65 N/A 92.25
MW-4 99.50 99.00 89.00 N/A 7.21 N/A 92.29
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A N/A N/A N/A
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured after AFVR at 4:45 PM on November 16, 2022.
Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Product Depth to Water Product Thickness Groundwater Elevation
MW-1 100.00 98.00 88.00 N/A 7.28 0.00 92.72
MW-2 99.58 97.58 87.58 N/A 6.84 0.00 92.74
MW-3 99.90 95.90 85.90 N/A N/A N/A N/A
MW-4 99.50 99.00 89.00 N/A N/A N/A N/A
MW-5 98.40 96.40 86.40 N/A N/A N/A N/A
MW-6 99.92 96.92 86.92 N/A N/A N/A N/A
VEW-1 99.34 76.34 71.34 N/A N/A N/A N/A
Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet; groundwater levels measured five days after AFVR on November 21, 2022.
X22-1939B

APPENDIX A
AFVR DATA REPORT

(PREPARED BY ADVANCED ENVIRONMENTAL)

AFVR FIELD LOG:
CLIENT: Paragon Environmental
JOB NAME: CSA Headquarters Drive
LOCATION: Greensboro, NC
AFVR EVENT DATES: November 16, 2022
EXTRACTION POINTS: MW-1 and MW-2
AES JOB NUMBER: 11 - 2280
DATE TIME FLOW (f/m) HUM.(%) TEMP. (F)VOC's(ppm)VAC. (hg")GALLONS STINGER/WL's EXTRACTION POINTS (hg")
MW-1 MW-2
Stinger(ft)10,11 9,11
Start 8:35 Initial WL's 7.18 6.41
01/11/00 8:40 3,200 99.0 46 15,000 19.0 13.0 15.0
9:40 3,500 99.0 77 8,000 17.0 11.0 14.0
10:40 3,700 99.0 95 5,000 16.0 9.0 13.5
11:40 3,700 99.0 102 6,000 15.0 9.0 13.0
12:40 3,700 99.0 103 6,000 15.0 410 gal.9.0 12.0
13:40 4,000 99.0 96 8,000 14.0 8.0 10.0
14:40 4,000 99.0 100 6,000 14.0 8.0 10.0
15:40 4,000 99.0 99 4,000 14.0 7.0 10.0
Final WL's 11.03 11.23
End 16:35 Total fluids: 832 gal.
Total free product:sheen
DATE TIME EXTRACTION POINTS (hg") cont. VACUUM INFLUENCE (h20")WELL GAUGING (ft)
MW-3 MW-4 MW-3 MW-4
Start 8:35 Stinger (ft)
initial WL's 7.11 6.65
11/16/22 8:40 0.00 0.65
9:40 0.00 1.30
10:40 0.05 1.40
11:40 0.10 1.40
12:40 0.05 1.40
13:40 0.05 0.75
14:40 0.05 1.00
15:40 0.05 1.25
Final wl's 7.65 7.21
End 16:35

APPENDIX B
WELL CONSTRUCTION RECORDS

APPENDIX C
LIQUIDS DISPOSAL MANIFEST