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Home My WebLink AboutWS-2837_6948_CA_MMPE_20230417 TABLE OF CONTENTS EXECUTIVE SUMMARY ........................................................................................................ 1 1.0 INTRODUCTION ....................................................................................................... 2 1.1 Site Information ................................................................................................... 2 1.2 Contacts Information ........................................................................................... 2 1.3 UST System Information ...................................................................................... 3 2.0 RECEPTOR SURVEY UPDATE ................................................................................... 4 2.1 Water Supply Wells ............................................................................................. 5 2.2 Public Water Supplies .......................................................................................... 5 2.3 Surface Water ...................................................................................................... 5 2.4 Wellhead Protection Areas .................................................................................. 5 2.5 Deep Aquifers in the Coastal Plain Physiographic Region ................................... 5 2.6 Subsurface Structures .......................................................................................... 5 2.7 Land Use .............................................................................................................. 5 2.8 Site Geology, Hydrogeology, and Soils ................................................................ 6 2.9 Hydraulic Conductivity Data from CSA Addendum ............................................. 6 3.0 CAP SUMMARY ....................................................................................................... 6 3.1 Remediation Progress Summary (Remedial Actions To Date) ............................ 7 3.2 On-Site Discharges ............................................................................................... 7 3.3 Explanation of Cleanup Goals .............................................................................. 7 4.0 MMPE EVENT .......................................................................................................... 7 5.0 WATER TABLE MONITORING .................................................................................. 8 6.0 GROUNDWATER SAMPLING & ANALYSIS .............................................................. 8 6.1 Benzene ............................................................................................................... 8 6.2 Methyl Tertiary-butyl Ether (MTBE) .................................................................... 8 6.3 Naphthalene ........................................................................................................ 8 6.4 Ethylene Dibromide (EDB) ................................................................................... 9 6.5 Vertical Extent of Dissolved Hydrocarbons ......................................................... 9 7.0 MNA & SOURCE DEPLETION ......................................................................................... 9 7.1 Soil Contaminant Mass ........................................................................................ 9 7.2 Groundwater – Total Mass of Contaminant ...................................................... 10 8.0 CONCLUSIONS & RECOMMENDATIONS ............................................................... 10 9.0 STATEMENT & CERTIFICATION ............................................................................. 11 Page 1 TABLE OF CONTENTS (CONTINUED) FIGURES: 1) Topographic Map 2) Site Map TABLES: 1) UST Information (in text page 2) 2) Surrounding Properties Within 1,000 feet 3) Monitoring Well Detail 4) Groundwater Elevation Data 5) Groundwater Analytical Data APPENDICES: A) MMPE Report, Calculation Sheet, & Non-Hazardous Waste Manifest B) Summary of Free-Phase Product Recovery Table C) Groundwater Contaminant Mass Calculations ________________________________________________________________________ Page 2 ACRONYMS AFVR ............... Aggressive Fluid Vapor Recovery BLS .................. Below Land Surface BTEX .............. Benzene, Toluene, Ethylbenzene, & Xylenes CFR ................. Code of Federal Regulations COC ................ Chain of Custody CSA ................. Comprehensive Site Assessment CAP ................. Corrective Action Plan DEQ ................ Department of Environmental Quality EPH ................. Extractable Petroleum Hydrocarbons GCLs ............... Gross Contaminant Levels HASP ............... Health & Safety Plan LSA ................. Limited Site Assessment MADEP ........... Massachusetts Department of Environmental Protection MMPE ............ Mobile Multi-Phase Extraction MSCC .............. Maximum Soil Contaminant Concentration MTBE .............. Methyl Tertiary Butyl Ether µg/L ................ Micrograms per Liter mg/kg ............. Milligrams per kilogram MW ................ Monitoring Well NCAC .............. North Carolina Administrative Code OSHA .............. Occupational Safety and Health Administration OVA ................ Organic Vapor Analyzer PPM ................ Parts Per Million PID .................. Photo-ionization Detector QA/QC ............ Quality Assurance / Quality Control SCFM .............. Standard Cubic Feet per Minute SW .................. Water Supply Well UST ................. Underground Storage Tank US EPA ............ United States Environmental Protection Agency VPH ................ Volatile Organic Hydrocarbons Page 3 Free Product Recovery Report – Sprinkle Gas Station #2 1 Pyramid Project # 2023-029 04/24/2023 EXECUTIVE SUMMARY On behalf of Jerry & Annie Rich, Pyramid Environmental & Engineering, P.C. (Pyramid) has completed the Monitoring Report for the Sprinkle Gas #2 site. The site is located at 1400 W. Gate City Boulevard in Greensboro, Guilford County, North Carolina. Sprinkle Gas #2 was operated as a gasoline station from the mid 1960’s until motor fuel sales ceased in 2012. The first set of Underground Storage Tanks (USTs) were operated from 1966 until they were removed in 1990. At that time, several hundred tons of contaminated soil was removed and treated on site. The new UST systems were coated-steel USTs which were installed in the same excavation and were operated from 1990 until they were removed in October 2015. Most of the surrounding properties are owned by the University of North Carolina at Greensboro (UNCG). On February 17, 2016, Pyramid emailed the list of properties to Terri L. Cartner, Director of Property, Projects and Business Enterprises for the UNCG. Ms. Cartner checked available records and sent the list back indicating that all properties are using public water service accounts and confirming the areas UNCG owns. The remaining surveys were sent and the returned surveys all indicated municipal water supply. Since 2016, more surrounding properties have been acquired by UNCG. A search for supply wells was conducted by walking and driving the surrounding area within 1,500 feet of the site, and no water supply wells were found. The area is served by the City of Greensboro Municipal water. Between July 2017 and April 2020, four (4) AFVR events have been completed at the site to recover free- phase product and dissolved hydrocarbons from monitoring wells MW-2 and MW-7. A total of 1,183-gallons of contaminated groundwater were recovered during the four (4) AFVR events, and the total amount of gasoline recovered as vapors was calculated to be 38.48 gallons equivalent of 240.5 pounds of hydrocarbon mass removed in the 4 AFVR events. On August 30, 2022, MW-2 and MW-7 were gauged and free-product (FP) was detected in the UST source area in MW-7. The amount of FP measured in MW-7 was measured as 0.41 feet which is about 4.92 inches. Dissolved groundwater concentrations in MW-2 showed detections of benzene, MTBE, naphthalene, 1,2,4- tri-methylbenzene, and tert-butylbenzene above NCAC 2L Groundwater Standards. During the August 2022 groundwater sampling event, no detected compounds were above GCLs. An MMPE event was completed at the site from March 20 to March 24, 2023. Monitoring well MW-7 was gauged for free product, and 0.1 feet or 1.2 inches of free product was detected in MW-7 prior to starting the MMPE event. During the event, a total of 3,845 gallons contaminated groundwater and free product was recovered for proper disposal. Field readings and calculations indicate a total amount of petroleum hydrocarbons removed during the MMPE event was 205.56 pounds or 32.89 gallons of gasoline as vapor. On April 20, 2023, twenty-seven (27) days after the MMPE event, monitoring well MW-7 was gauged, and no free product or sheen (<1/16 inch) was detected in MW-7. Free Product Recovery Report – Sprinkle Gas Station #2 2 Pyramid Project # 2023-029 04/24/2023 1.0 INTRODUCTION On behalf of Jerry & Annie Rich, Pyramid Environmental & Engineering, P.C. (Pyramid) has completed the Free Product Recovery Report for the Sprinkle Gas #2 site. The report summarizes the results of the March 2023 (Mobile Multi-Phase Extraction) MMPE event and gauging event. The site is located at 1400 W. Gate City Blvd., (formerly Lee Street) in Greensboro, Guilford County, North Carolina. The location of the site is shown on a portion of the Greensboro, NC USGS topographic map presented as Figure 1. A site map showing the buildings, former UST locations, and monitoring wells is presented as Figure 2. Sprinkle Gas #2 was operated as a gasoline station from the mid 1960’s until fuel sales ceased in 2012. The initial Underground Storage Tanks (USTs) were installed in 1966 and removed in 1990 and replaced with new USTs. The second set of USTs was removed in October 2015. The USTs are listed on Table 1 below. Currently Sprinkle Gas #2 is operating as an oil change and minor vehicle repair shop. An aboveground storage tank (AST) is used to hold the crankcase oil from vehicles, and the oil is picked up and recycled by Noble Oil. 1.1 Site Information • Site Name/Occupant: Sprinkle Gas #2 • Location: 1400 W. Gate City Blvd., Greensboro, NC • Site Detail Information: Figure 1 (Topo Map), Figure 2 (Site Detail Map) • Groundwater Incident: 6934 • Facility I.D. No.: 0-009838 • UST Owner/Operator: Jerry & Annie Rich • Property Owner: Jerry & Annie Rich • Latitude/Longitude: N. Lat 36.062810˚ / W. Long. -79.813412˚ 1.2 Contacts Information • Responsible Party: Mr. Jerry Rich 5213 Platte Drive McLeansville, NC 27301 (336) 621-0897 • Consultant/Contractor: Pyramid Environmental & Engineering, P.C. 503 Industrial Avenue, Greensboro, NC 27406 (336) 335-3174 mike@pyramidenvironmental.com Free Product Recovery Report – Sprinkle Gas Station #2 3 Pyramid Project # 2023-029 04/24/2023 • Analytical Laboratories: Pace Analytical Services, LLC 9800 Kincey Ave. Suite 100 Huntersville, NC (704) 875-9092 NC Drinking Water Certification # 37706 NC Wastewater Certification # 12 1.3 UST System Information Table 1 UST Information Tank No. Install Date Size in Gallons Tank Dimensions Last Contents Last Used New UST Release? Additional Comments D-1 1990 5,000 13.5’ X 8’ Diesel Dec. 2012 No Removed 10/06/15 K-1 1990 3,000 18’ X 64” Kerosene Dec. 2012 No Removed 10/06/15 P-1 1990 5,000 13.5’ X 8’ Mid. Gas Dec. 2012 No Removed 10/06/15 R-1 1990 5,000 13.5 X 8’ Reg. Gas Dec. 2012 No Removed 10/06/15 S-1 1990 4,000 23.5’ X 64” Prem. Gas Dec. 2012 No Removed 10/06/15 W-1 1990 1,000 10’9” X 48” Used Oil Dec. 2012 No Removed 10/06/15 In November 1990, during upgrade activities for the UST systems, a petroleum release was reported by the DEQ representative. In 1990, the DEQ assigned the site regulatory incident # 6948. The USTs were removed for replacement with new USTs. The UST system lines and tanks removed in 1990 appeared to be in relatively good shape and the DEQ comments suggested that the release was probably not a large quantity. In October 1992, free-product was detected in the SW well and was reported to Guilford County at that time. There are several potential off-site sources of product mentioned in the original CSA from 1993 including: the property to the west of Sprinkle # 2 which was owned by Gulf Oil; the railroad which loaded and unloaded fuel to the Gulf terminal over the years; and the downgradient gas station and Vanstory bulk fuel facility across Lee Street from the site. The Vanstory operations included a gasoline station directly across Lee Street from the Sprinkle # 2 site. The UST removal project in 1990 removed several hundred yards of contaminated soil which was placed on a thick plastic liner and treated on site. No groundwater was encountered in the tank excavations. In the mid-1990’s, the DEQ did not require a Corrective Action Plan (CAP), probably because the site was in the city and municipal water was available to all areas surrounding the site. Free Product Recovery Report – Sprinkle Gas Station #2 4 Pyramid Project # 2023-029 04/24/2023 The Comprehensive Site Assessment (CSA) for the site was prepared in May 1993, which was the basis for other work completed at the site including free-phase petroleum product recovery events. The free-phase petroleum product recovery efforts have resulted in reduction of free-phase petroleum product in SW (renamed to MW-2 in 2016) which was used for recovery. On September 8, 2014, the DEQ sent an NOV letter requiring completion of a CSA Addendum. The pre-approval was returned to the DEQ on September 16, 2014 and was approved in January 2015. During 2015, Pyramid met with the DEQ concerning the site and UST removal project. In July 2015, it was determined in a meeting with DEQ WSRO, DEQ Trust Fund, and Pyramid that the UST removal project must be completed before the CSA Addendum. The UST removals were completed in October 2015, and the report was accepted in a DEQ letter dated December 2015. After receiving the approval for the UST removal report, Pyramid prepared the access agreements in December 2015. The access agreements were obtained from the State Property Office in January. During the CSA Addendum, seven Type II groundwater monitoring wells were installed at the site to better assess the groundwater concentrations at the site. The monitoring well locations are indicated on Figure 2. As part of the CSA Addendum, Pyramid collected 10 soil samples for laboratory analysis. The analytical results from the risk-based soil analysis showed no concentrations of petroleum contaminants above the STGW or residential MSCCs. 2.0 RECEPTOR SURVEY UPDATE In February 2016, a receptor survey was completed for the Sprinkle Gas #2 site. Property information was obtained from the Guilford County Geographic Information Services (GIS), and well surveys were distributed to the property owners surrounding the site. The site is located southwest of downtown Greensboro, NC in an area of commercial, industrial, and residential use. Supply well surveys were mailed to property owners within 700 feet of the subject property as shown on Table 2. Most of the surrounding properties are owned by the University of North Carolina at Greensboro (UNCG). On February 17, 2016, Pyramid emailed the list of properties on Table 2 to Terri L. Cartner, Director of Property, Projects and Business Enterprises for the UNCG. Ms. Cartner checked available records and sent the list back indicating that all properties are using public water service accounts and confirming the areas UNCG owns. As indicated on Table 2 (in blue), most of the developed properties within the radius are owned by UNCG. The remaining surveys were sent, and the returned surveys all indicated municipal water supply. A search for supply wells was conducted by Free Product Recovery Report – Sprinkle Gas Station #2 5 Pyramid Project # 2023-029 04/24/2023 walking and driving the surrounding area within 1,500 feet of the site, and no water supply wells were found. ADJOINING PROPERTY USE: Commercial/Industrial PUBLIC WATER AVAILABILITY: Available to all the surrounding area SUPPLY WELLS WITHIN 1,500 FEET: None found. 2.1 Water Supply Wells The receptor survey and surrounding area reconnaissance confirmed all properties within the 1,000-foot radius of Sprinkle Gas #2 are connected to municipal water supply and that no water supply wells were observed. 2.2 Public Water Supplies The receptor survey and surrounding area reconnaissance confirmed all properties within the 1,000-foot radius of Sprinkle Gas #2 are connected to municipal water. 2.3 Surface Water Surface run-off on the subject site flows to the south into the storm water drainage system along Gate Cite Boulevard (former Lee Street). Mile Run Creek is the nearest surface water oriented due south at a distance of approximately 800 feet from Sprinkle #2 site. 2.4 Wellhead Protection Areas There are no designed wellhead protection areas within 1,500 feet of the site. 2.5 Deep Aquifers in the Coastal Plain Physiographic Region This site is not in the Coastal Plain Physiographic Region, and this section is not applicable to this site. 2.6 Subsurface Structures No shallow subsurface structures were identified in the source area that would affect contaminant migration. The depth to water in the area is about 20 feet BLS. 2.7 Land Use The surrounding area is primary commercial, institutional (UNCG), with some residential properties >750 feet east and south of the site. Free Product Recovery Report – Sprinkle Gas Station #2 6 Pyramid Project # 2023-029 04/24/2023 2.8 Site Geology, Hydrogeology, and Soils Pyramid’s review of the 1985 Geologic Map of North Carolina yielded information concerning local geology and hydrogeology. Based on this review, the site is in the Carolina Slate Belt of North Carolina. The surface geology consists of regional soils created by the weathering of underlying bedrock. According to the 1985 Geologic Map of North Carolina, the underlying bedrock beneath the site is metamorphosed felsic granitic rock, map symbol CZg. In general, both surface and groundwater flow directions are controlled by topographic contours of landforms in the Piedmont with flow occurring perpendicular to the contours from high to low elevations. Surface run-off on the subject site flows to the south into the storm water drainage system along Lee Street. Mile Run Creek is the nearest surface water oriented approximately due south and approximately 800 feet from the Sprinkle #2 site. Field observations indicate the soil samples were tan to brown, clayey-silty-sand at shallow depths, and increasing in sand content and durability with depth. The depth to the water table in this area is approximately 20 feet BLS. Pyramid prepared a soil sampling and analysis plan for the Sprinkle Gas # 2 site which was included with the DEQ pre-approval. The details of the work are presented in the following sections. The 1993 well log for MW-5D showed partially weathered rock from a depth of 50 feet to the total depth of the boring 68 feet BLS. The saprolitic soils above 50 feet appear to contain most of the petroleum contaminants. 2.9 Hydraulic Conductivity Data from CSA Addendum The groundwater information from the CSA Addendum Report is summarized below: • The depth to groundwater in the source area is between 19 and 23 feet BLS. • The groundwater gradient was 0.012 ft/ft to the southeast. • The hydraulic conductivity was calculated to be 0.288 feet/day • The average linear groundwater velocity is approximately 0.0143 feet/day or 5.3 feet/year. 3.0 CAP SUMMARY Preparation of a Corrective Action Plan (CAP) was not directed or pre-approved by the NCDEQ ; therefore, no CAP has been completed for the site. Free Product Recovery Report – Sprinkle Gas Station #2 7 Pyramid Project # 2023-029 04/24/2023 3.1 Remediation Progress Summary (Remedial Actions To Date) Between July 2017 and April 2020, four (4) AFVR events have been completed at the site to recover free-phase product and dissolved hydrocarbons from monitoring wells MW-2 and MW-7. A total of 1,183-gallons of contaminated groundwater were recovered during the four (4) AFVR events, and the total amount of gasoline recovered as vapors was calculated to be 38.48 gallons or 240.5 pounds of hydrocarbon mass were removed during the (4) AFVR events. The March 2023 MMPE event was completed at the site to remove free product and contaminated groundwater. The current MMPE event is discussed in Section 4.0 of this report. 3.2 On-Site Discharges There are no on-site discharges of treated groundwater or other remediation processes. 3.3 Explanation of Cleanup Goals The site is an intermediate risk site requiring removal of free-phase petroleum product to <1/8 inch and groundwater cleanup to below Gross Contaminated Levels. (GCLs). The source of drinking water in the area is the City of Greensboro municipal water. 4.0 MMPE EVENT Between March 20 through March 24, 2023, a MMPE event was completed at the Sprinkle Gas #2 site to recover free-product and reduce high levels of total petroleum hydrocarbons in monitoring well MW-7. Prior to starting the MMPE, monitoring well MW-7 was gauged for free-phase petroleum product, and 0.1 feet or 1.2 inches was detected in MW-7. During the AFVR event, monitoring well MW-7 was used as the recovery well. During the 96-hour event, the fluids recovered in the vacuum truck was 3,845 gallons, and the total amount of gasoline recovered as vapors was calculated to be 32.89 gallons or 205.56 pounds of hydrocarbon mass removal. The MMPE event data, calculations, certificate of disposal, and manifest is included in Appendix A. A summary of the free product and petroleum contaminated groundwater recovery events are included in Table B-8 A (see Appendix B). On April 20, 2020, monitoring well MW-7 was gauged for free-phase product, and No free-phase petroleum product ( < 1/16 inch ) was observed in MW-7, gauged 27 days after the MMPE event. Free Product Recovery Report – Sprinkle Gas Station #2 8 Pyramid Project # 2023-029 04/24/2023 5.0 WATER TABLE MONITORING Monitor well construction details are presented on Table 3. The current and historical depth to groundwater measurements are summarized in Table 4. During the August 2022 groundwater sampling event, free-phase petroleum product was detected in MW-7 (0.41 feet or 4.92 inches), and no free-phase product was detected in MW-2. On April 20, 2020, monitoring well MW-7 was gauged for free-phase product, and No free-phase petroleum product ( < 1/16 inch ) was observed in MW-7, gauged 27 days after the MMPE event. 6.0 GROUNDWATER SAMPLING & ANALYSIS On August 30, 2022, a groundwater sample was collected from NCDEQ the approved monitoring well (MW-2). The current analytical data from the monitoring and supply wells are summarized in Table 5. The groundwater sample collected was analyzed for volatile organic compounds using Standard Method 6200B. The results for the main contaminants of concern detected during the August 2022 groundwater monitoring event are discussed in the following sections. 6.1 Benzene During the August 2022 sampling event, benzene was detected in MW-2 at a concentration above the North Carolina Administrative Code (NCAC) 2L Groundwater Standard of 1 microgram per liter (µg/l). The laboratory results for MW-2 detected benzene at a concentration of 439 µg/l. Since monitoring well MW-7 had approximately 4.92 inches of free product, MW-7 was not sampled. During the current and November 2019 sampling event, none of the concentrations were above Gross Contaminant Level (GCL) for benzene. 6.2 Methyl Tertiary-butyl Ether (MTBE) The current sampling event detected Methyl tert-butyl ether (MTBE) in MW-2 at a concentration of 22.8 µg/l, which is above the NCAC 2L Groundwater Standard of 20 µg/l. None of the concentrations were above GCL for MTBE (November 2019 and August 2022). 6.3 Naphthalene The current sampling event detected Naphthalene in MW-2 at a concentration of 184 µg/l, which is above the NCAC 2L Groundwater Standard of 6 µg/l. In August 2022, MW-7 was not sampled for laboratory analysis. During this sampling event and previous sampling events, none of the concentrations were above GCLs for naphthalene. Free Product Recovery Report – Sprinkle Gas Station #2 9 Pyramid Project # 2023-029 04/24/2023 6.4 Ethylene Dibromide (EDB) During previous sampling events, EDB was detected in MW-7 above NCAC 2L Groundwater Standards and above GCLs in monitoring well MW-7. The current and precious sampling events, all other monitoring wells sampled contained EDB below laboratory limits of detection. 6.5 Vertical Extent of Dissolved Hydrocarbons The 1993 CSA included the installation of a deep groundwater monitoring well placed next to a contaminated shallow well. The deep monitoring well was sampled in March 2016, and the results showed no detections of petroleum hydrocarbons. The August 2022 groundwater sampling was the latest sampling event, and no dissolved petroleum concentrations were detected above the NCDEQ GCLs. 7.0 MNA & SOURCE DEPLETION The latest gauging of MW-7 showed no free-product detected in this monitoring well, or in any other monitoring well at the Sprinkle # 2 site. At this time, the most recent groundwater analyses have shown no dissolved concentrations above the NC DEQ Gross Contaminant Levels (GCLs). The NCDEQ regulatory closure goals are : • Removal of free-phase product to less than 1/8 inch for a year • And reduction of dissolved gasoline compounds (benzene & EDB) below GCLs for a year. The most recent MMPE Event was successful in reducing the free-product levels in MW-7 to below detection, and removing over 3,845 gallons of petroleum contaminated groundwater to reduce dissolved concentrations. At this time, the next step in the process of seeking regulatory closure is to collect groundwater samples for the site. In the future, Monitoring Natural Attenuation (MNA) may be appropriate for Sprinkle # 2, provided that free-phase petroleum product does not return. 7.1 Soil Contaminant Mass During the CSA Addendum completed in 2016, soil samples were collected and analyzed by risk- based methods. The analytical results from the risk-based soil analyses showed no concentrations of petroleum contaminants above the STGW or residential MSCCs. Due to the CSA Addendum soil assessment results, no soil contaminant mass was calculated. No CAP was directed for the site; therefore, no soil contaminant mass baseline or remedial milestones were established. Free Product Recovery Report – Sprinkle Gas Station #2 10 Pyramid Project # 2023-029 04/24/2023 7.2 Groundwater – Total Mass of Contaminant Pyramid calculated a total mass of contaminant for groundwater for the March 2016 sampling event, and calculated a total mass of contaminant for groundwater for the April 2018 sampling event. The calculated groundwater mass for March 2016 was 1.50E + 10 micrograms, and the calculated groundwater mass for November 2019 was 6.50E + 9 micrograms. The calculated groundwater mass for August 2022 was 6.29E + 9 micrograms. A slight reduction in groundwater mass was detected and calculated for the current sampling event. The groundwater mass of contaminant calculations are presented in Appendix C. No CAP has been completed for the site, so no groundwater mass baseline nor projected remedial milestones were established for the Sprinkle Gas #2 site. 8.0 CONCLUSIONS & RECOMMENDATIONS As directed and pre-approved by the NCDEQ, Pyramid completed a MMPE event at the Sprinkle Gas #2 site. A summary of the MMPE event and recommendation are presented below. • Between March 20th and March 24th, 2023, the MMPE event was completed at the Sprinkle Gas #2 site to recover free-phase petroleum product and reduce high levels of dissolved petroleum hydrocarbons in groundwater at the location of MW-7. • Prior to the MMPE, gasoline product was detected in MW-7 (0.1 feet or 1.2 inches). • During the 96-hour MMPE event, 3,845 gallons of liquids and the total amount of gasoline recovered as vapors was calculated to be 32.89 gallons (approximately 205.56 pounds of hydrocarbon mass removed). • Groundwater flow is to the southeast, the average depth to groundwater was 21.07 feet. • On April 20, 2023, after the MMPE event, 0.0 feet (0.00 inches) of free-phase (gasoline) petroleum product was detected in monitoring well MW-7. • The last sampling event was August 2022. No other targeted parameters were detected at concentrations above the GCL standards. Based on the recent free product recovery event and historical groundwater monitoring results, Pyramid recommends the NCDEQ consider regulatory closure with soil and groundwater notice of residual petroleum (NORP) deed restriction. FIGURES TABLES Parcel Number Owner Mail Address Mail City Mail State Mail Zip Property Address Appraisal Model Code Property Type Structure Size Lot Size Year Built Receptor Survey 0009123 ARTICHOKETWO LP 6100 W FRIENDLY AVE GREENSBORO NC 27410 1300 W GATE CITY BLVD INDUSTRIAL Industrial 4560 0.33 1941 CITY 0011696 BISHARA, ESSA J ; BISHARA, NAJWAH G 3900 MEREDITH DR GREENSBORO NC 27408 1601 SPRING GARDEN ST RESTAURANTS RETAIL 1682 0.25 1948 NA 0011697 BISHARA, ESSA J ; BISHARA, NAJWAH G 3900 MEREDITH DR GREENSBORO NC 27408 604 S AYCOCK ST Commercial 0 0.13 NA 0011741 BISHARA, ESSA J ; BISHARA, NAJWAH G 3900 MEREDITH DR GREENSBORO NC 27408 810 S AYCOCK ST AUTOSALES/REP Industrial 1600 0.17 2003 NA 0009138 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 1227 W GATE CITY BLVD COMM Commercial 3109 0.05 1938 CITY 0009139 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 1225 W GATE CITY BLVD COMM Commercial 3836 0.08 1941 CITY 0009140 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 812 GLENWOOD AVE Commercial 0 0.16 CITY 0009141 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 812 GLENWOOD AVE Vacant 0 0.16 CITY 0009142 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 816 GLENWOOD AVE SFR Commercial 1456 0.18 1915 CITY 0009143 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 818 GLENWOOD AVE SFR Commercial 1364 0.18 1925 CITY 0009144 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 820 GLENWOOD AVE COMM/SERV Commercial 1400 0.18 1989 CITY 0009153 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 833 MCCORMICK ST RESIDENTIAL 0 0.18 CITY 0009154 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 809 MCCORMICK ST CLUBS/LODGES OFFICE 8200 0.54 1961 CITY 0009155 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 807 MCCORMICK ST Industrial 0 0.18 CITY 0009156 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 805 MCCORMICK ST Industrial 0 0.18 CITY 0009157 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 803 MCCORMICK ST INDUSTRIAL Industrial 5200 0.34 1962 CITY 0009158 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 801 MCCORMICK ST WAREHOUSE Commercial 6800 0.21 1945 CITY 0009159 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 1201 W GATE CITY BLVD AUTOSALES/REP Commercial 1188 0.61 1957 CITY 0009160 CAPITAL FACILITIES FOUNDATION INC P O BOX 26170 GREENSBORO NC 27402 1231 W GATE CITY BLVD Industrial 0 0.03 CITY 0011708 CIRCLE K STORES INC 2440 WHITEHALL PARK DR #800 CHARLOTTE NC 28273 1550 W GATE CITY BLVD CONVENIENCE STORE Commercial 5024 2.17 1999 NA 0009282 CITY OF GREENSBORO PO BOX 3136 GREENSBORO NC 27402 607 S AYCOCK ST GOVERNMENT OWNED 0 0.63 CITY 0011740 GLOVER, JAMES S ; GLOVER, SHERYL M 1911 TROSPER RD GREENSBORO NC 27455 1501 W GATE CITY BLVD COMM/SERV Industrial 2286 0.31 1951 NA 0009130 HOLDER, KEITH OBRIAN 8306 PURGASON LN STOKESDALE NC 27357 811 S AYCOCK ST AUTOSALES/REP Industrial 3600 0.34 1977 NR 0009145 JACKE, MICHAEL L 609 JOYNER STREET GREENSBORO NC 27403 822 GLENWOOD AVE SFR Commercial 802 0.18 1948 NA 0011698 K & S PROPERTIES LLC 322 S DAVIE ST GREENSBORO NC 27401 1208 OAKLAND AVE COMM/SERV OFFICE 8652 1.05 1955 NA 0011742 KENDRICKS, JAMES T ; KENDRICKS, BECKY M 2105 CARPENTER ST GREENSBORO NC 27403 812 S AYCOCK ST Industrial 0 0.68 NA 0009121 LEMMONS, WILLIAM R JR 8306 NEWBERRY STREET STOKESDALE NC 27357 1310 W GATE CITY BLVD WAREHOUSE Industrial 8000 0.48 1938 NR 0009132 N C DEPT OF TRANSPORTATION R/W DEPT GREENSBORO NC 27415 1415 W GATE CITY BLVD Commercial 0 0.19 CITY 0009298 NB CORPORATION PO BOX 4466 GREENSBORO NC 27404 727 729 KENILWORTH ST Industrial 0 0.21 NA 0009301 NB CORPORATION PO BOX 4466 GREENSBORO NC 27404 725 KENILWORTH ST INDUSTRIAL Industrial 13692 0.39 1954 NA 0009146 PALMETTO EQUITY GROUP INC PO BOX 4606 GREENSBORO NC 27404 824 GLENWOOD AVE SFR Commercial 1378 0.18 1946 NA 0009118 RICH, JERRY N ; RICH, ANNIE L 1400 W GATE CITY BLVD GREENSBORO NC 27403 1400 W GATE CITY BLVD SERVICE STATION Industrial 570 0.83 1945 CITY 0011707 ROMANA HOLDING LLC ; STEINWAY HOLDING CORP 33 RIVERSIDE DR NEW YORK NY 10023 1500 W GATE CITY BLVD FASTFOODS Commercial 3188 0.88 1987 NA 0011701 SARJI, GEORGE ; SARJI, VIVIAN 2102 BURNTLEAF PL GREENSBORO NC 27410 602 S AYCOCK ST Commercial 0 0.16 NA 0009125 SNYDER, FRED T JR ; SNYDER, STEPHEN MARK 1800 SPRING GARDEN ST GREENSBORO NC 27403 807 S AYCOCK ST COMM Commercial 2986 0.34 1976 CITY 0009116 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1410 W GATE CITY BLVD Vacant 0 2.5 CITY 0009120 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1312 W GATE CITY BLVD INDUSTRIAL Industrial 6060 0.32 1940 CITY 0009124 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1200 W GATE CITY BLVD Industrial 0 2.67 CITY 0009127 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1409 W GATE CITY BLVD INDUSTRIAL Industrial 11448 0.51 1930 CITY TABLE 2 Receptor Survey 03-07-16 Sprinkle Gas # 2 - 1400 West. Lee Street DEQ Incident # 6948 0009128 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1401 W GATE CITY BLVD INDUSTRIAL Industrial 4973 0.63 1946 CITY 0009129 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 840 NEAL ST HOSPITAL-PRIVATE Industrial 32990 5.14 1957 CITY 0009131 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 836 NEAL ST Vacant 0 0.53 CITY 0009133 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1319 W GATE CITY BLVD INDUSTRIAL Industrial 43788 1.25 1940 CITY 0009134 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1317 W GATE CITY BLVD WAREHOUSE Industrial 7480 0.58 1986 CITY 0009135 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1306 HAYWOOD ST Industrial 0 1.31 CITY 0009136 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1301 W GATE CITY BLVD OFFICE Industrial 1950 0.27 1953 CITY 0009137 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 1300 HAYWOOD ST Industrial 0 1.84 CITY 0009152 STATE OF NORTH CAROLINA 1321 MAIL SERVICE CENTER RALEIGH NC 27699 835 MCCORMICK ST SFR RESIDENTIAL 956 0.18 1935 CITY 0009259 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1540 SPRING GARDEN ST GARDENAPT Apartment 14300 0.74 1985 CITY 0009265 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1517 SPRING GARDEN ST Commercial 0 0.5 CITY 0009266 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1515 SPRING GARDEN ST Vacant 0 0.98 CITY 0009267 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1513 SPRING GARDEN ST Vacant 0 0.17 CITY 0009268 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1511 SPRING GARDEN ST Vacant 0 0.18 CITY 0009269 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1509 SPRING GARDEN ST OFFICE OFFICE 1044 0.36 1948 CITY 0009270 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1507 SPRING GARDEN ST RESIDENTIAL 0 0.4 CITY 0009272 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1407 SPRING GARDEN ST DUPLEX/TRIPLEX RESIDENTIAL 2244 0.29 1899 CITY 0009273 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1401 SPRING GARDEN ST RESIDENTIAL 0 0.42 CITY 0009274 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 705 KENILWORTH ST Industrial 0 0.24 CITY 0009275 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1100 OAKLAND AVE INDUSTRIAL Industrial 1200 0.22 1971 CITY 0009276 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1104 OAKLAND AVE GOVERNMENT OWNED 0 0.86 CITY 0009277 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1114 OAKLAND AVE GOVERNMENT OWNED 0 0.91 CITY 0009278 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1116 OAKLAND AVE GOVERNMENT OWNED 0 0.42 CITY 0009279 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1118 OAKLAND AVE GOVERNMENT OWNED 0 0.17 CITY 0009280 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1120 OAKLAND AVE GOVERNMENT OWNED 0 0.23 CITY 0009281 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1122 OAKLAND AVE GOVERNMENT OWNED 0 0.24 CITY 0009283 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 605 S AYCOCK ST SFR GOVERNMENT OWNED 1328 0.17 1919 CITY 0009284 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1505 SPRING GARDEN ST GOVERNMENT OWNED 0 0.3 CITY 0009285 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1503 SPRING GARDEN ST RESIDENTIAL 0 0.29 CITY 0009286 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 726 KENILWORTH ST Commercial 0 0.14 CITY 0009287 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 700 724 KENILWORTH ST RESIDENTIAL 0 0.09 CITY 0009288 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 728 KENILWORTH ST COMM/SERV Commercial 750 0.08 1965 CITY 0009289 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1110 OAKLAND AVE GOVERNMENT OWNED 0 0.17 CITY 0009290 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1108 OAKLAND AVE GOVERNMENT OWNED 0 0.17 CITY 0009291 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1307 R1 SPRING GARDEN ST INSTITUTIONAL 0 0.04 CITY 0009294 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 612 STIRLING ST Vacant 0 0.21 CITY 0009295 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 614 STIRLING ST Vacant 0 0.21 CITY 0009296 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 616 STIRLING ST Vacant 0 0.17 CITY 0009297 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 618 STIRLING ST Vacant 0 0.18 CITY 0009299 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 723 KENILWORTH ST PUBLICCLG GOVERNMENT OWNED 6558 0.54 1973 CITY 0009300 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 620 STIRLING ST WAREHOUSE INSTITUTIONAL 6000 0.28 1956 CITY 0009302 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1309 SPRING GARDEN ST OFFICE 0 0.3 CITY 0009303 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1307 SPRING GARDEN ST OFFICE 0 0.27 CITY 0009304 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1000 1098 OAKLAND AVE Industrial 0 0.95 CITY 0009318 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 623 STIRLING ST Vacant 0 0.67 CITY 0009324 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 617 STIRLING ST Vacant 0 0.63 CITY 0011693 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1204 OAKLAND AVE OFFICE 0 0.87 CITY 0011695 STATE OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1605 SPRING GARDEN ST OFFICE Commercial 5180 0.58 1988 CITY 0009126 TRI STORES LLC 2302 W MEADOWVIEW RD GREENSBORO NC 27407 1411 W GATE CITY BLVD CONVENIENCE STORE Commercial 6288 1.3 1999 RTS 0011694 TULL, JOEL S 3005 PISGAH CT GREENSBORO NC 27455 1607 SPRING GARDEN ST APT<5 UNITS Commercial 4872 0.49 1925 NA 0009258 UNIVERSITY OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1557 WALKER AVE PUBLICCLG GOVERNMENT OWNED 1512 19.16 1999 CITY 0009271 UNIVERSITY OF NORTH CAROLINA 116 W JONES ST RALEIGH NC 27603 1501 SPRING GARDEN ST Vacant 0 0.33 CITY 0009119 WELLS, MARY M M TRUSTEE 608 HOBBS ST GREENSBORO NC 27403 1308 W GATE CITY BLVD LIGHTMFG Industrial 5700 0.31 1948 NR 0009122 WELLS, MARY M M TRUSTEE 608 HOBBS ST GREENSBORO NC 27403 1302 W GATE CITY BLVD LIGHTMFG Industrial 10260 0.4 1946 NR Blue = Property owned by The University of North Carolina at Greensboro Public Water = City Not Returned = NRRed = Site Returned to Sender = RTS Not Available = NA Yellow = Receptor Survey Mailer sent out on 03/07/16 Well Installation Top of Casing Total well Bottom of Top of Well Number Year Elevation depth Screen Screen Diameter (feet)(feet)(feet)(feet)(inches) MW-1 97.05 32.00 32.00 17.00 2.00 MW-2 96.83 29.00 29.00 19.00 4.00 (SW-Well) MW-3 96.12 30.00 30.00 15.00 2.00 MW-4 96.54 30.00 30.00 15.00 2.00 MW-5D 97.33 65.00 65.00 60.00 2.00 (MW-5) MW-6 98.72 30.00 30.00 15.00 2.00 MW-7 97.46 30.00 30.00 15.00 2.00 MW-8 96.56 30.00 30.00 15.00 2.00 MW-9 97.66 30.00 30.00 15.00 2.00 MW-10 97.27 30.00 30.00 15.00 2.00 MW-11 96.17 30.00 30.00 15.00 2.00 MW-12 100.00 31.50 31.50 21.50 4.00 (NE-Well) 1400 West Lee Street, Guilford County, Greensboro, NC 1992 1992 2016 1993 2016 2016 2016 1992 2016 1993 Table 3 Monitoring Well Construction Details Sprinkle Gas #2 - Incident # 6948 2016 2016 Well Date Top of Casing Depth to Depth To Free-Product Groundwater Number Gauged Elevation Free Product Groundwater Thickness Elevation (feet)(feet)(feet)(feet)(feet) MW-1 03/02/16 97.05 None 21.21 None 75.84 08/02/16 97.05 None 21.54 None 75.51 02/07/17 97.05 None 23.04 None 74.01 07/27/17 97.05 None 21.81 None 75.24 04/16/18 97.05 NG NG NG NG 11/20/19 97.05 None 20.78 None 76.27 07/02/20 97.05 NG NG NG NG 07/29/21 97.05 NG NG NG NG 08/30/22 97.05 NG NG NG NG 02/04/16 96.83 20.29 20.30 0.01 76.53 MW-2 02/22/16 96.83 None 20.28 None 76.55 (SW-Well)03/02/16 96.83 None 20.25 None 76.58 08/02/16 96.83 21.23 21.35 0.12 75.48 02/07/17 96.83 Sheen 22.53 Sheen 74.30 07/27/17 96.83 21.87 21.92 0.05 74.91 04/16/18 96.83 None 22.34 None 74.49 08/17/18 96.83 None 23.01 None 73.82 11/20/19 96.83 Sheen 20.31 Sheen 76.52 07/02/20 96.83 None 18.53 None 78.30 07/29/21 96.83 None 19.91 None 76.92 08/30/22 96.83 None 22.94 None 73.89 MW-3 03/02/16 96.12 None 19.40 None 76.72 08/02/16 96.12 None 20.20 None 75.92 02/07/17 96.12 None 21.66 None 74.46 07/27/17 96.12 Sheen 20.89 Sheen 75.23 04/16/18 96.12 NG NG NG NG 11/20/19 96.12 NG NG NG NG 07/02/20 96.12 NG NG NG NG 07/29/21 96.12 NG NG NG NG 08/30/22 96.12 NG NG NG NG MW-4 03/02/16 96.54 None 19.74 None 76.80 08/02/16 96.54 Sheen 20.24 Sheen 76.30 07/27/17 96.54 NG NG NG NG 04/16/18 96.54 NG NG NG NG 11/20/19 96.54 NG NG NG NG 07/02/20 96.54 NG NG NG NG 07/29/21 96.54 NG NG NG NG 08/30/22 96.54 NG NG NG NG MW-5 D 03/02/16 97.33 None 20.98 None 76.35 08/06/12 97.33 NG NG NG NG 07/27/17 97.33 None 22.34 None 74.99 04/16/18 97.33 NG NG NG NG 11/20/19 97.33 NG NG NG NG 07/02/20 97.33 NG NG NG NG 07/29/21 97.33 NG NG NG NG 08/30/22 97.33 NG NG NG NG MW-6 03/02/16 98.72 None 21.91 None 76.81 08/02/16 98.72 None 22.59 None 76.13 07/27/17 98.72 NG NG NG NG 04/16/18 98.72 NG NG NG NG 11/20/19 98.72 None 21.83 None 76.89 07/02/20 98.72 NG NG NG NG 07/29/21 98.72 NG NG NG NG 08/30/22 98.72 NG NG NG NG Table 4 Groundwater Elevation Data Sprinkle Gas #2 DEQ Incident # 6948 1400 West Lee Street, Greensboro, NC Table 4 Groundwater Elevation Data Sprinkle Gas #2 DEQ Incident # 6948 1400 West Lee Street, Greensboro, NC MW-7 03/02/16 97.46 None 20.88 None 76.58 08/02/16 97.46 None 21.60 None 75.86 02/07/17 97.46 None 23.07 None 74.39 07/27/17 97.46 None 22.24 None 75.22 04/16/18 97.46 22.84 22.86 0.02 74.60 08/13/18 97.46 23.03 23.77 0.74 73.69 08/31/18 97.46 22.86 23.01 0.15 74.45 11/20/19 97.46 20.78 20.86 0.08 76.60 04/02/20 97.46 18.34 18.41 0.07 79.05 04/10/20 97.46 None 19.38 None 78.08 07/02/20 97.46 None 18.54 None 78.92 07/29/21 97.46 20.30 20.305 0.005 77.16 08/30/22 97.46 23.33 23.74 0.410 73.72 03/20/23 97.46 21.50 21.60 0.100 75.86 04/20/23 97.46 None 21.25 None 76.21 MW-8 03/02/16 96.56 None 20.31 None 76.25 08/02/16 96.56 None 20.93 None 75.63 02/07/17 96.56 None 23.48 None 73.08 07/27/17 96.56 None 21.53 None 75.03 04/16/18 96.56 None 22.20 None 74.36 11/20/19 96.56 None 20.17 None 76.39 07/02/20 96.56 NG NG NG NG 07/29/21 96.56 NG NG NG NG 08/30/22 96.56 NG NG NG NG MW-9 03/02/16 97.66 None 22.22 None 75.44 08/02/16 97.66 None 22.33 None 75.33 02/07/17 97.66 None 23.98 None 73.68 07/27/17 97.66 None 22.41 None 75.25 04/16/18 97.66 NG NG NG NG 11/20/19 97.66 None 21.43 None 76.23 07/02/20 97.66 NG NG NG NG 07/29/21 97.66 NG NG NG NG 08/30/22 97.66 NG NG NG NG MW-10 03/02/16 97.27 None 22.83 None 74.44 08/02/16 97.27 None 22.98 None 74.29 07/27/17 97.27 NG NG NG NG 04/16/18 97.27 NG NG NG NG 11/20/19 97.27 None 22.22 None 75.05 07/02/20 97.27 NG NG NG NG 07/29/21 97.27 NG NG NG NG 08/30/22 97.27 NG NG NG NG MW-11 03/02/16 96.17 None 20.50 None 75.67 08/06/12 96.17 None 20.96 None 75.21 07/27/17 96.17 NG NG NG NG 04/16/18 96.17 NG NG NG NG 11/20/19 96.17 NG NG NG NG 07/02/20 96.17 NG NG NG NG 07/29/21 96.17 NG NG NG NG 08/30/22 96.17 NG NG NG NG MW-12 03/02/16 100.00 None 23.74 None 76.26 (NE-Well)08/06/12 100.00 NG NG NG NG 07/27/17 100.00 NG NG NG NG 04/16/18 100.00 NG NG NG NG 11/20/19 100.00 NG NG NG NG 07/02/20 100.00 NG NG NG NG 07/29/21 100.00 NG NG NG NG 08/30/22 100.00 NG NG NG NG NG = Not Gauged.NM = Not Measured < 1/8 inch of Product (Approximately 1/16 inch in Bailor) PARAMETER UNITS DATE NCAC 2L Gross Contaminant MW-1 MW-2 MW-3 MW-4 MW-5D MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12 Groundwater Level (GCL) (SW) (MW-5)(NE)Standard Standard Method 6200B Benzene ug/l 03-03-16 2810 2080 ND 15.8 ND ND 8640 2850 ND ND ND ND 1 5000 08-02-16 2820 2570 21.1 ND NS ND 9490 2120 9.0 ND ND NS 02-07-17 2250 3100 1.4 NS NS NS 8440 1980 5.3 NS NS NS 07-27-17 1350 1960 1.8 NS 1.0 NS 837 2750 19.5 NS NS NS 04-16-18 NS NS NS NS NS NS 7240 2100 NS NS NS NS 11-20-19 1690 1110 NS NS NS ND 4070 1420 ND ND NS NS 07-29-21 NS NS NS NS NS NS 4700 NS NS NS NS NS 08-30-22 NS 439 NS NS NS NS FP NS NS NS NS NS Toluene ug/l 03-03-16 2070 198 ND 3.9 ND ND 12400 7100 1.4 ND 12.9 ND 600 260000 08-02-16 1780 310 4.8 ND NS ND 19400 5460 4.8 ND 7 NS 02-07-17 1330 238 ND NS NS NS 16500 5620 2.5 NS NS NS 07-27-17 759 207 ND NS ND NS 1520 7220 2.5 NS NS NS 04-16-18 NS NS NS NS NS NS 13100 6910 NS NS NS NS 11-20-19 526 35.5 NS NS NS ND 13800 5210 ND ND NS NS 07-29-21 NS NS NS NS NS NS 17700 NS NS NS NS NS 08-30-22 NS 3.1 NS NS NS NS FP NS NS NS NS NS Ethylbenzene ug/l 03-03-16 317 118 125 40.4 ND ND 632 619 28.9 ND 55.6 ND 600 84500 08-02-16 335 273 49.1 86.1 NS ND 1140 625 35.3 ND 79.7 NS 02-07-17 266 669 57.4 NS NS NS 943 666 23.9 NS NS NS 07-27-17 192 265 46.7 NS ND NS 91.2 573 64.7 NS NS NS 04-16-18 NS NS NS NS NS NS 571 639 NS NS NS NS 11-20-19 236 157 NS NS NS ND 998 537 ND ND NS NS 07-29-21 NS NS NS NS NS NS 1450 NS NS NS NS NS 08-30-22 NS 177 NS NS NS NS FP NS NS NS NS NS Total Xylenes ug/l 03-03-16 1464 1261 469 106.4 ND ND 3590 3840 202.3 ND 305 ND 500 85500 08-02-16 1519 2058 131 322 NS ND 6560 3550 323 ND 586 NS 02-07-17 1235 3620 213.7 NS NS NS 5760 3850 157.7 NS NS NS 07-27-17 854 1494 160.2 NS 0.54 NS 498 3490 179.2 NS NS NS 04-16-18 NS NS NS NS NS NS 3310 3830 NS NS NS NS 11-20-19 898 716 NS NS NS ND 5750 3270 1.7 ND NS NS 07-29-21 NS NS NS NS NS NS 8490 NS NS NS NS NS 08-30-22 NS 347.2 NS NS NS NS FP NS NS NS NS NS Total BTEX ug/l 03-03-16 6661 3657 594 166.5 ND ND 25262 14409 232.6 ND 373.5 ND No Standard No Standard 08-02-16 6454 5211 206 408.1 NS ND 36590 11755 372.1 ND 672.9 NS 02-07-17 5081 7627 272.5 NS NS NS 31643 12116 189.4 NS NS NS 07-27-17 3155 3926 208.7 NS 1.54 NS 29462 14033 265.9 NS NS NS 04-16-18 NS NS NS NS NS NS 24221 12840 NS NS NS NS 11-20-19 3350 2018.5 NS NS NS ND 24618 10437 1.7 ND NS NS 07-29-21 NS NS NS NS NS NS 32340 NS NS NS NS NS 08-30-22 NS 966.3 NS NS NS NS FP NS NS NS NS NS MTBE ug/l 03-03-16 4100 131 ND ND ND ND 26000 1470 310 ND ND ND 20 20000 08-02-16 5350 113 ND ND NS ND 20100 1030 361 ND ND NS 02-07-17 4870 144 ND NS NS NS 18600 970 243 NS NS NS 07-27-17 3340 115 ND NS ND NS 2210 1290 538 NS NS NS 04-16-18 NS NS NS NS NS NS 18600 853 NS NS NS NS 11-20-19 3880 40.7 NS NS NS ND 7800 892 29.7 ND NS NS 07-29-21 NS NS NS NS NS NS 5960 NS NS NS NS NS 08-30-22 NS 22.8 NS NS NS NS FP NS NS NS NS NS MONITORING WELL Groundwater Analytical Results TABLE 5 Sprinkle Gas #2 - Incident # 6978 1400 West Lee Street, Guilford County, Greensboro, NC PARAMETER UNITS DATE NCAC 2L Gross Contaminant MW-1 MW-2 MW-3 MW-4 MW-5D MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12 Groundwater Level (GCL) (SW) (MW-5)(NE)Standard Standard MONITORING WELL Groundwater Analytical Results TABLE 5 Sprinkle Gas #2 - Incident # 6978 1400 West Lee Street, Guilford County, Greensboro, NC Isopropyl Ether ug/l 03-03-16 445 321 ND 0.58 1.5 ND 1290 189 108 ND ND ND 70 70000 08-02-16 532 19.8 0.81 ND NS ND 1270 152 102 ND ND NS 02-07-17 480 346 ND NS NS NS 1360 158 72.4 NS NS NS 07-27-17 302 285 ND NS 1.6 NS 126 196 148 NS NS NS 04-16-18 NS NS NS NS NS NS 999 126 NS NS NS NS 11-20-19 327 106 NS NS NS ND 511 91.6 4.8 ND NS NS 07-29-21 NS NS NS NS NS NS 319 NS NS NS NS NS 08-30-22 NS 62.8 NS NS NS NS FP NS NS NS NS NS Naphthalene ug/l 03-03-16 274 211 85.9 82.9 ND ND ND 288 11.5 ND 34.9 ND 6 6000 08-02-16 285 294 104 123 NS ND 455 240 35.0 ND 200 NS 02-07-17 275 663 98 NS NS NS 380 304 29.7 NS NS NS 07-27-17 154 265 81.4 NS ND NS 42.7 229 68.4 NS NS NS 04-16-18 NS NS NS NS NS NS 303 267 NS NS NS NS 11-20-19 241 184 NS NS NS ND 429 225 ND ND NS NS 07-29-21 NS NS NS NS NS NS 520 NS NS NS NS NS 08-30-22 NS 184 NS NS NS NS FP NS NS NS NS NS Isopropylbenzene ug/l 03-03-16 28.4 ND 42.3 8.1 0.85 ND ND 33.7 2.1 ND 23.4 ND 70 25000 08-02-16 32.4 283 9.6 41.8 NS ND ND 38.1 4.6 ND 27.7 NS 02-07-17 26.3 64.9 24.3 NS NS NS ND 39 3.5 NS NS NS 07-27-17 20.2 17.5 22.1 NS 1.5 NS ND 28.2 8.8 NS NS NS 04-16-18 NS NS NS NS NS NS ND 33 NS NS NS NS 11-20-19 27.6 9.3 NS NS NS ND ND 30.2 ND ND NS NS 07-29-21 NS NS NS NS NS NS 84.2 NS NS NS NS NS 08-30-22 NS 12.2 NS NS NS NS FP NS NS NS NS NS n-propylbenzene ug/l 03-03-16 54.3 17 119 8.7 ND ND ND 72.1 1.8 ND 39.2 ND 70 30000 08-02-16 61.9 42.3 10.6 132 NS ND 131 91.5 7.2 ND 47.3 NS 02-07-17 50.3 156 70.9 NS NS NS 114 94.3 5.6 NS NS NS 07-27-17 39.3 ND ND NS ND NS ND ND ND NS NS NS 04-16-18 NS NS NS NS NS NS ND 80.3 NS NS NS NS 11-20-19 45.5 18.4 NS NS NS ND ND ND ND ND NS NS 07-29-21 NS NS NS NS NS NS 223 NS NS NS NS NS 08-30-22 NS 25.9 NS NS NS NS FP NS NS NS NS NS 1,2-Dichloroethane ug/l 03-03-16 96.5 27.1 ND 1.8 ND ND 164 30.3 21.4 ND ND ND 0.4 400 08-02-16 104 23.4 2.4 ND NS ND 137 ND 21.8 ND ND NS 02-07-17 93.6 27.5 2.1 NS NS NS 119 ND 15.8 NS NS NS 07-27-17 50.4 28.1 2.3 NS 0.51 NS 13.4 ND 32 NS NS NS 04-16-18 NS NS NS NS NS NS 120 ND NS NS NS NS 11-20-19 52.8 7 NS NS NS ND ND ND 2.2 ND NS NS 07-29-21 NS NS NS NS NS NS ND NS NS NS NS NS 08-30-22 NS <2 NS NS NS NS FP NS NS NS NS NS 1,2,4-trimethylbenzene ug/l 03-03-16 263 556 907 22.7 ND ND 748 704 ND 1.3 287 ND 400 28500 08-02-16 291 919 26.5 775 NS ND 1070 744 56.4 0.84 535 NS 02-07-17 227 2410 421 NS NS NS 966 801 15.7 NS NS NS 07-27-17 200 698 383 NS 1.1 NS 99.7 609 20.8 NS NS NS 04-16-18 NS NS NS NS NS NS 484 724 NS NS NS NS 11-20-19 194 414 NS NS NS ND 942 570 ND ND NS NS 07-29-21 NS NS NS NS NS NS 1890 NS NS NS NS NS 08-30-22 NS 422 NS NS NS NS FP NS NS NS NS NS 1,3,5-trimethylbenzene ug/l 03-03-16 ND 218 333 ND ND ND 198 171 95.1 0.56 111 ND 400 25000 08-02-16 ND 327 ND 354 NS ND 279 207 175 ND 121 NS 02-07-17 ND 846 176 NS NS NS 257 215 72.4 NS NS NS 07-27-17 ND 257 164 NS ND NS 25.5 173 58.6 NS NS NS 04-16-18 NS NS NS NS NS NS 110 188 NS NS NS NS 11-20-19 ND 178 NS NS NS ND ND ND 2.9 ND NS NS 07-29-21 NS NS NS NS NS NS 512 NS NS NS NS NS 08-30-22 NS 148 NS NS NS NS FP NS NS NS NS NS PARAMETER UNITS DATE NCAC 2L Gross Contaminant MW-1 MW-2 MW-3 MW-4 MW-5D MW-6 MW-7 MW-8 MW-9 MW-10 MW-11 MW-12 Groundwater Level (GCL) (SW) (MW-5)(NE)Standard Standard MONITORING WELL Groundwater Analytical Results TABLE 5 Sprinkle Gas #2 - Incident # 6978 1400 West Lee Street, Guilford County, Greensboro, NC n-butylbenzene ug/l 03-03-16 ND ND 66.8 1.6 ND ND ND ND ND 2.6 ND ND 70 6900 08-02-16 ND ND 2.0 98.6 NS ND ND ND ND 1.9 30.9 NS 02-07-17 ND ND ND NS NS NS ND ND ND NS NS NS 07-27-17 ND ND ND NS ND NS ND ND ND NS NS NS 04-16-18 NS NS NS NS NS NS ND ND NS NS NS NS 11-20-19 ND ND NS NS NS ND ND ND ND 1.2 NS NS 07-29-21 NS NS NS NS NS NS ND NS NS NS NS NS 08-30-22 NS <2 NS NS NS NS FP NS NS NS NS NS tert-butylbenzene ug/l 03-03-16 ND ND ND 1.8 ND ND ND ND ND ND ND ND 70 15000 08-02-16 ND ND ND ND NS ND ND ND ND ND ND NS 02-07-17 ND ND ND NS NS NS ND ND ND NS NS NS 07-27-17 ND ND ND NS ND NS ND ND ND NS NS NS 04-16-18 NS NS NS NS NS NS ND ND NS NS NS NS 11-20-19 ND ND NS NS NS ND ND ND ND ND NS NS 07-29-21 NS NS NS NS NS NS ND NS NS NS NS NS 08-30-22 NS 347 NS NS NS NS FP NS NS NS NS NS sec-butylbenzene ug/l 03-03-16 13.4 ND 36.8 3.6 ND ND ND ND ND 2.0 10.5 ND 70 5000 08-02-16 ND 14.0 4.6 44.6 NS ND ND ND ND 1.5 17.3 NS 02-07-17 ND 55.7 16.7 NS NS NS ND ND ND NS NS NS 07-27-17 ND ND ND NS ND NS ND ND ND NS NS NS 04-16-18 NS NS NS NS NS NS ND ND NS NS NS NS 11-20-19 ND ND NS NS NS ND ND ND ND 0.89 NS NS 07-29-21 NS NS NS NS NS NS ND NS NS NS NS NS 08-30-22 NS <2 NS NS NS NS FP NS NS NS NS NS chloroform ug/l 03-03-16 ND ND ND ND ND ND ND ND ND 20.9 ND ND 70 70000 08-02-16 ND ND ND ND NS ND ND ND ND 19.7 ND NS 02-07-17 ND ND ND NS NS NS ND ND ND NS NS NS 07-27-17 ND ND ND NS ND NS ND ND ND NS NS NS 04-16-18 NS NS NS NS NS NS ND ND NS NS NS NS 11-20-19 ND ND NS NS NS ND ND ND ND 5.4 NS NS 07-29-21 NS NS NS NS NS NS ND NS NS NS NS NS 08-30-22 NS <2 NS NS NS NS FP NS NS NS NS NS EDB ug/l 08-02-16 ND ND ND ND NS ND 249 ND 10.7 ND ND NS 0.02 50 02-07-17 ND ND ND NS NS NS 249 ND 5.5 NS NS NS 07-27-17 ND ND ND NS ND NS 18.6 ND ND NS NS NS 04-16-18 NS NS NS NS NS NS 177 ND NS NS NS NS 11-20-19 ND ND NS NS NS ND 148 ND 0.86 ND NS NS 07-29-21 NS NS NS NS NS NS 83.5 NS NS NS NS NS 08-30-22 NS <2 NS NS NS NS FP NS NS NS NS NS Method 504.1 EDB ug/l 03-03-16 NA NA NA NA NA ND 131 8.3 12.4 ND ND NA 0.02 50 Method 3030C Lead ug/l 03-03-16 NA NA NA NA NA 7.2 47 ND ND ND ND NA 15 15000 MADEP - VPH C5-C8 Aliphatics ug/l 03-03-16 NA NA NA NA NA ND 81100 32400 1260 ND 367 NA 400 No Standard C9-C12 Aliphatics ug/l 03-03-16 NA NA NA NA NA ND 11800 9100 682 101 2080 NA 700 No Standard C9-C10 Aromatics ug/l 03-03-16 NA NA NA NA NA ND 4100 6480 547 134 2100 NA 200 No Standard FP = Free Product NS = Not Sampled NI = Not Installed Bold Values exceed the NCAC 2L Standard ND = Not Detected NA = Not Analyzed for this parameter Highlighted and bold values exceed the GCL Standard APPENDIX A MOBILE MULTI-PHASE EXTRACTION REPORT SITE LOCATION Sprinkle Gas 2 (EPA ID # 6948) 1400 W. Gate City Blvd. (Lee Street) Greensboro, NC Prepared For: Pyramid Environmental & Engineering PC PO Box 16265 Greensboro, NC 27416 Phone: (336) 335-3174 March 31, 2023 TABLE OF CONTENTS • EVENT SUMMARY • DISPOSAL MANIFESTS MOBILE MULTI-PHASE EXTRACTION EVENT SUMMARY March 31, 2023 Location: Sprinkle Gas #2 (EPA ID # 6948) 1400 W. Gate City Blvd. Greensboro, NC Client: Pyramid Environmental & Engineering PC Greensboro, NC LPT Job Number # 22-102 Event Date: March 20, 2023 – March 24, 2023 Personnel: Danny Oldham MMPE System: 300 CFM MMPE System Extraction Wells: MW-7 Well Initial FP Final FP Stinger Depth Run Time MW-7 0.1 feet 0 23 feet 96 hrs. Description of Events: The MMPE event ran from 12:00 p.m. March 20, 2023 through 12:00 p.m. March 24, 2023. The MMPE system was active for approximately 96 hours. During the event, vacuum at the recovery pump was 25 inches of mercury (hg). Effective vacuum was achieved while connected to one well (MW-7) that has showed free-product. Temperature ranged from 58 - 180 degrees F and humidity was 95 percent. Total field gauged volatile organic compounds decreased from initial reading of 263 to 2,405 parts per-million (PPM) throughout the event. Groundwater / Product Mix Recovered: During the event, a total of 3,845 gallons of product/water mix were recovered from the site and properly disposed at a certified North Carolina disposal facility. Total fluids recovered, was measured based on stick readings conducted during and following the event. Based on 96 hours of operation and a total 3,845 gallons recovered during the event, the average groundwater recovery rate from one well calculated to be approximately 40.05 gallons per hour. Event Results: During the event, a total of 3,845 gallons of product/water mix was recovered and properly disposed of at a North Carolina disposal facility. The OVA/OVM/PID readings indicate a total hydrocarbons removed during this event in pounds were estimated to be 205.56 pounds. Total vapors recovered were calculated to be 32.89 gallons. The total amount of gasoline recovered as vapors was estimated to be 32.89 gallons. Client:Pyramid Environmental Job Name:Sprinkle Gas #2 (EPA ID # 6948) Location:1400 W. Gate City Blvd., Greensboro, NC MMPE Event Dates:03/20/2023 to 03/24/2023 LPT Job #:23-101 3/20/2023 12:45 111.35 4 90 58 263 6 23 0 15408 3/20/2023 13:15 117.5 4 95 170 1,400 6 24 3/20/2023 13:45 119.03 4 95 180 1,672 6 24 3/20/2023 14:30 120.57 4 95 178 2,083 6 24 3/20/2023 16:30 119.8 4 95 172 2,215 6 24 3/21/2023 8:00 115.19 4 95 174 1,500 6 25 3/21/2023 9:00 119.03 4 95 172 1,473 6 25 3/21/2023 10:00 118.26 4 95 178 1,456 6 25 3/21/2023 11:00 115.96 4 95 175 1,223 6 25 3/21/2023 12:00 117.5 4 95 173 1,175 6 25 16370 (962) 3/21/2023 13:00 115.19 4 95 174 1,050 6 25 3/21/2023 14:00 116.73 4 95 172 1,112 6 25 3/21/2023 15:00 118.26 4 95 178 1,073 6 25 3/22/2022 7:00 115.96 4 95 176 1,841 6 25 3/22/2022 8:00 117.5 4 95 176 1,776 6 25 3/22/2022 10:00 118.26 4 95 174 1,853 6 25 3/22/2022 12:00 119.8 4 95 175 1,980 6 25 17270 (900) 3/22/2022 13:00 119.03 4 95 175 1,875 6 25 3/22/2022 14:00 119,03 4 95 174 1,690 6 25 3/22/2022 15:00 118.26 4 95 176 1,705 6 25 3/22/2022 16:00 119.8 4 95 172 1,685 6 25 3/23/2023 7:00 119.03 4 95 174 1,880 6 25 3/23/2023 10:00 115.96 4 95 173 1,997 6 25 3/23/2023 11:00 119,03 4 95 175 2,405 6 25 ( 3/23/2023 12:00 119.8 4 95 177 2,393 6 25 18240 (970) 3/23/2023 13:00 118.26 4 95 174 2,354 6 25 3/23/2023 14:00 119.03 4 95 176 2,324 6 25 3/23/2023 15:00 118.26 4 95 178 1,975 6 25 3/23/2023 16:00 119.03 4 95 178 1,892 6 25 3/24/2023 10:00 116.73 4 95 178 1,596 6 25 3/24/2023 11:00 119.03 4 95 176 1,543 6 25 19214 (974) 3/24/2023 12:00 119.03 4 95 176 1275 6 25 Total: 3,806 gallons Notes: For OVA calibrated with methane, K=1 For OVM calibrated with hexane, K=6 System Vac. (in. of Hg) Tank Stick (in.)K*Flow Meter MMPE Field Data Sheet Date Time Exhaust Velocity (cfm)Exhaust Diameter (in.)Humidity %Temp (F)OVA/OVM (ppm) Calculation of Hydrocarbon Mass Removal as Gasoline from MMPE Event SITE:Sprinkle Gas #2 MMPE Event DATE: Total Removed to Date from last Spreadsheet:25.39 gallons Date of last Spreadsheet: Step #2 - Calculate Mass Removal Rate for Hydrocarbons as Gasoline Flow Relative Humidity OVA/OVM Date Time Rate Temp Temp Temp Humidity Bws *PPMw Qstd K PPMc Cc PMRc PMRg (military)(cfm)(deg. F)(deg. C)(deg. R)%(mass ratio)30 (dscfm)**(ppm)(lb/hr)(lb/hr) 3/20/2023 12:45 111.35 58 14.44 518 90 0.0280 263.00 110.32 6 1623.4568 0.0000506 0.3347 0.3874 3/20/2023 13:15 117.5 170 76.67 630 95 0.128 1400 85.87 6 9633.0275 0.0003001 1.5460 1.7892 3/20/2023 13:45 119.03 180 82.22 640 95 0.35 1672 63.83 6 15433.846 0.0004808 1.8412 2.1309 3/20/2023 14:30 120.57 178 81.11 638 95 0.35 2083 64.86 6 19227.692 0.0005989 2.3308 2.6974 3/20/2023 16:30 119.8 172 77.78 632 95 0.35 2215 65.06 6 20446.154 0.0006369 2.4861 2.8771 3/21/2023 8:00 115.19 174 78.89 634 95 0.35 1500 62.36 6 13846.154 0.0004313 1.6137 1.8675 3/21/2023 9:00 119.03 172 77.78 632 95 0.35 1473 64.64 6 13596.923 0.0004235 1.6426 1.9010 3/21/2023 10:00 118.26 178 81.11 638 95 0.35 1456 63.62 6 13440 0.0004187 1.5980 1.8494 3/21/2023 11:00 115.96 175 79.44 635 95 0.35 1223 62.67 6 11289.231 0.0003517 1.3224 1.5304 3/21/2023 12:00 117.5 173 78.33 633 95 0.35 1175 63.71 6 10846.154 0.0003379 1.2914 1.4946 3/21/2023 13:00 116.73 174 78.89 634 95 0.35 1050 63.19 6 9692.3077 0.0003019 1.1447 1.3247 3/21/2023 14:00 118.96 172 77.78 632 95 0.35 1112 64.60 6 10264.615 0.0003197 1.2393 1.4343 3/21/2023 15:00 115.96 178 81.11 638 95 0.35 1073 62.38 6 9904.6154 0.0003085 1.1547 1.3364 3/22/2023 7:00 117.5 176 80.00 636 95 0.35 1841 63.41 6 16993.846 0.0005294 2.0139 2.3307 3/22/2023 8:00 118.26 176 80.00 636 95 0.35 1776 63.82 6 16393.846 0.0005107 1.9553 2.2629 3/22/2023 10:00 119.8 174 78.89 634 95 0.35 1853 64.85 6 17104.615 0.0005328 2.0732 2.3993 3/22/2023 12:00 119.03 175 79.44 635 95 0.35 1980 64.33 6 18276.923 0.0005693 2.1976 2.5433 3/22/2023 13:00 119.03 175 79.44 635 95 0.35 1875 64.33 6 17307.692 0.0005391 2.0810 2.4084 3/22/2023 14:00 118.26 174 78.89 634 95 0.35 1690 64.02 6 15600 0.0004859 1.8665 2.1601 3/22/2023 15:00 119.8 176 80.00 636 95 0.35 1705 64.65 6 15738.462 0.0004903 1.9016 2.2007 3/22/2023 16:00 119.03 172 77.78 632 95 0.35 1685 64.64 6 15553.846 0.0004845 1.8790 2.1746 3/23/2023 7:00 115.96 174 78.89 634 95 0.35 1880 62.77 6 17353.846 0.0005406 2.0360 2.3562 3/23/2023 10:00 119.03 173 78.33 633 95 0.35 1997 64.54 6 18433.846 0.0005742 2.2235 2.5732 3/23/2023 11:00 119.8 175 79.44 635 95 0.35 2405 64.75 6 22200 0.0006915 2.6865 3.1092 3/23/2023 12:00 118.26 177 80.56 637 95 0.35 2393 63.72 6 22089.231 0.0006881 2.6305 3.0443 3/23/2023 13:00 119.03 174 78.89 634 95 0.35 2354 64.43 6 21729.231 0.0006769 2.6168 3.0284 3/23/2023 14:00 118.26 176 80.00 636 95 0.35 2324 63.82 6 21452.308 0.0006682 2.5587 2.9612 3/23/2023 15:00 119.03 178 81.11 638 95 0.35 1975 64.03 6 18230.769 0.0005679 2.1817 2.5249 3/23/2023 16:00 116.73 178 81.11 638 95 0.35 1892 62.79 6 17464.615 0.0005440 2.0496 2.3721 3/24/2023 10:00 118.26 178 81.11 638 95 0.35 1596 63.62 6 14732.308 0.0004589 1.7516 2.0272 3/24/2023 11:00 119.03 176 80.00 636 95 0.35 1543 64.23 6 14243.077 0.0004437 1.7099 1.9788 3/24/23 12:00 119.03 176 80.00 636 95 0.3500 1275 64.23 6 11769.231 0.0003666 1.4129 1.6351 4/2/2020 March 20 - 24, 2023 Step #1 - Calculate Vapor Flow Rate Step #3 - Calculate Total Hydrocarbons Removed Exhaust Exhaust Exhaust Flow System System Total Total Date Time Diam.Area Velocity Rate Date Time PMRg Operation Operation Removed Removed (military)(inches)(ft2)(ft/sec)(cfm)(military)(lb/hr)(days)(hours)(lbs)(gallons) 3/20/2023 12:45 0.3874 0:00 0.750 0.291 0.046 3/20/2023 13:15 1.7892 0:00 0.500 0.895 0.143 3/20/2023 13:45 2.1309 0:00 0.500 1.065 0.170 3/20/2023 14:30 2.6974 0:00 0.750 2.023 0.324 3/20/2023 16:30 2.8771 0:00 1.000 2.877 0.460 3/21/2023 8:00 1.8675 0:00 15.500 28.946 4.631 3/21/2023 9:00 1.9010 0:00 1.000 1.901 0.304 3/21/2023 10:00 1.8494 0:00 1.000 1.849 0.296 3/21/2023 11:00 1.5304 0:00 1.000 1.530 0.245 3/21/2023 12:00 1.4946 0:00 1.000 1.495 0.239 3/21/2023 13:00 1.3247 0:00 1.000 1.325 0.212 3/21/2023 14:00 1.4343 0:00 1.000 1.434 0.229 3/21/2023 15:00 1.3364 0:00 1.000 1.336 0.214 3/22/2023 7:00 2.3307 0:00 16.000 37.291 5.966 3/22/2023 8:00 2.2629 0:00 1.000 2.263 0.362 3/22/2023 10:00 2.3993 0:00 2.000 4.799 0.768 3/22/2023 12:00 2.5433 0:00 2.000 5.087 0.814 3/22/2023 13:00 2.4084 0:00 1.000 2.408 0.385 3/22/2023 14:00 2.1601 0:00 1.000 2.160 0.346 3/22/2023 15:00 2.2007 0:00 1.000 2.201 0.352 3/22/2023 16:00 2.1746 0:00 1.000 2.175 0.348 3/23/2023 7:00 2.3562 0:00 15.000 35.344 5.655 3/23/2023 10:00 2.5732 0:00 3.000 7.720 1.235 3/23/2023 11:00 3.1092 0:00 1.000 3.109 0.497 3/23/2023 12:00 3.0443 0:00 1.000 3.044 0.487 3/23/2023 13:00 3.0284 0:00 1.000 3.028 0.485 3/23/2023 14:00 2.9612 0:00 1.000 2.961 0.474 3/23/2023 15:00 2.5249 0:00 1.000 2.525 0.404 3/23/2023 16:00 2.3721 0:00 1.000 2.372 0.380 3/24/2023 10:00 2.0272 0:00 18.000 36.489 5.838 3/24/2023 11:00 1.9788 0:00 1.000 1.979 0.317 3/24/23 12:00 1.6351 0:00 1.000 1.635 0.262 KEY Total hydrocarbon vapors removed as gasoline (this event):32.89 gallons * See Psychrometric Calculators at:Field Data Total hydrocarbon vapors removed as gasoline (this event):205.56 pounds http://www.rezine.net/WebCalcs/Psy/webpsyx.htm From Web or http://www.learninghelper.com/psyc Int. Calc. Total hydrocarbon vapors removed as gasoline (previous events):18.03 gallons Transferred ** For OVA (FID) calibrated with Methane, K=1; Results Total hydrocarbon vapors removed as gasoline (to date):50.92 gallons For OVM (PID) calibrated with Hexane, K=6. Previous APPENDIX B Date Method Wells Dia. Of Total Fluids Estimated Amount of Free Product of Recovery Used Wells Recovered (gallons)(LNAPL) Recovered (gallons) 7/10/2017 AFVR MW-2, MW-7, & MW-8 2 & 4 inch wells 231 2.75 gallons as vapors 8/17/2018 AFVR MW-2 and MW-7 2 & 4 inch wells 315 10.34 gallon as vapors 10/31/2019 AFVR MW-7 2 inch well 232 7.33 gallons as vapors 4/2/2020 AFVR MW-7 2 inch well 405 18.06 gallon as vapors 3/20 - 24/2023 MMPE MW-7 2-inch well 3,845 32.89 gallon as vapors MW-2:4-inch diameter well MW-7:2-inch diameter well MW-8:2-inch diameter well Sprinkle Gas #2 Free Product Recovery History Table 1400 W. Gate City Blvd. / Incident # 6948 Greensboro, Guilford County, North Carolina Table B-8 A: Summary of Free Product & Petroleum Contaminated Groundwater & Vapor Recovery APPENDIX C The baseline groundwater contaminant mass is estimated based on the highest analytical results from March 2016 sampling events. 6.29E+091-Aug-2022 2024.35 2070 15 10% 1.12E+10 Nov 2019 2093.24 2070 15 10%6.50E+09 April 2018 3611.81 2070 15 10% Groundwater Contaminant Mass Removal Calculation Sprinkle Gas #2 - NCDEQ Incident # 6948 Greensboro, Guilford County, NC Estimated Groundwater Contaminant Mass Based on Average VOC Concentrations [µg] March 2016 4839.1 2070 15 10%1.50E+10 Date Average VOC Concentrations in Monitoring Wells [µg/L] Area with Monitoring Wells [m2] Estimated Plume Depth [m] Estimated Porosity [%] MW ID Benzene Concentration (March 2016) MTBE Concentration (March 2016) Total Benzene Concentration (July 2017 & April 2018) MTBE Concentration (July 2017 & April 2018) MW-1 2810 4100 1350 3340 MW-2 2080 131 1960 115 MW-3 0 0 1.6 0 MW-5D 0 0 1 0 MW-6 0 0 0 0 MW-7 8640 26000 7240 18600 MW-8 2850 1470 2100 853 MW-9 0 310 19.5 538 MW-10 0 0 0 0 MW-11 0 0 0 0 Average 1638.00 3201.10 1267.21 2344.60 MW ID Benzene Concentration (Nov. 2019) MTBE Concentration (Nov. 2019) Benzene Concentration (Nov. 2019 & Aug 2022) MTBE Concentration (Nov. 2019 & Aug. 2022) MW-1 1690 3880 1690 3880 MW-2 1110 40.7 439 22.8 MW-3 0 0 0 0 MW-5D 0 0 0 0 MW-6 0 0 0 0 MW-7 4070 7800 4070 7800 MW-8 1420 892 1420 892 MW-9 0 29.7 0 29.7 MW-10 0 0 0 0 MW-11 0 0 0 0 Average 829.00 1264.24 761.90 1262.45 2024.35 Average Benzene & MTBE Added Together 4839.10 3611.81 Sprinkle Gas #2 Average Benzene & MTBE Added Together 2093.24