The URL can be used to link to this page

Home My WebLink AboutWS-7866_37182_CA_MRP_20201222GROUNDWATER MONITORING REPORT NORTHWEST SUPERETTE 1014 NC HIGHWAY 68 N. OAK RIDGE, NC 27409 GUILFORD COUNTY GROUNDWATER INCIDENT: 37182 FACILITY ID#: 00-0-0000009964 SITE RISK: HIGH LATITUDE: N 36° 07’ 48” LONGITUDE: W 79° 57’ 47” DECEMBER 22, 2020 FORMER UST OWNER: Willyn, Inc. 8531 NC Highway 49 S. Snow Camp, NC 27349-9210 Phone Number: (336) 430-9553 PROPERTY OWNER: NC Department of Transportation P. O. Box 14996 Greensboro, NC 27415 Phone Number: (336) 334-3228 PROPERTY OCCUPANT: Same as Property Owner CONSULTANT: Paragon Environmental Consultants, Inc. paragonenv@northstate.net P. O. Box 157 Thomasville, NC 27361 Phone Number: (336) 669-6037 ANALYTICAL LABORATORY: Meritech, Inc. State Certification Number: #165 642 Tamco Road Reidsville, NC 27320 Phone Number: (336) 342-4748 RELEASE INFORMATION: Date Discovered: 5/15/2008 Estimated Quantity of Release: Unknown Cause of Release: Unknown Source of Release: Dispenser Island Size and Contents: (1) 6,000 Gallon Diesel UST, (2) 6,000 Gallon Gasoline USTs, (1) 10,000 Gallon Gasoline UST, and (1) 1,000 Gallon Kerosene UST Received: 12/22/2020 December 22, 2020 Doug Williams Willyn, Inc. 8531 NC Highway 49 S. Snow Camp, NC 27349-9210 Reference: Groundwater Monitoring Report Northwest Superette 1014 NC Highway 68 N. Oak Ridge, Guilford County, NC Groundwater Incident # 37182 Facility ID # 00-0-0000009964 Dear Mr. Williams: In accordance with an approved Task Authorization Form (TAF) dated August 20, 2020 from the North Carolina Department of Environmental Quality (NCDEQ), contained herein is a Groundwater Monitoring Report for the release which occurred at the above referenced facility. The field activities for this project consisted of sampling the four remaining monitor wells at this site, as well as laboratory analyses of the collected groundwater samples. All activities were conducted in accordance with the NCDEQ guidelines and the requirements of 15A NCAC 2L .0115. Mr. Williams, if you have any questions regarding this report, please contact our office. Sincerely, Benjamin W. Robinson, L.G. Paragon Environmental Consultants, Inc. R20-818 PARAGON Environmental Consultants, Inc. P.O. Box 157 • Thomasville, NC 27361-0157 Business Ph: (336) 669-6037 • Fax: (336) 476-7708 EXECUTIVE SUMMARY 1. Free Product: Free product has not ever been detected in any monitor well, boring, or excavation at this site. 2. Contaminant Mass: The historical maximum contaminant mass was calculated from the data collected at the time of the Corrective Action Plan to be approximately 4,236.11 kilograms (kg). The current contaminant mass calculated after the most recent sampling event on October 15, 2020 was approximately 15.08 kg. An arbitrary milestone of 5% contaminant mass reduction per remediation event was chosen since the Corrective Action Plan for this site was prepared in 2011 and implemented before the 2020 RRD. These cleanup goals have been met in the remediation events conducted since the approval of the Corrective Action Plan. 3. Maximum Concentrations of Dissolved Groundwater Contaminants: Contaminant Result Well ID 2L Standard Benzene 1,290 ug/L (MW-1) 1 ug/L Toluene 4,220 ug/L (MW-1) 600 ug/L Ethylbenzene 731 ug/L (MW-1) 600 ug/L Xylenes (total) 5,620 ug/L (MW-1) 500 ug/L Isopropylbenzene 76 ug/L (MW-1) 70 ug/L Naphthalene 300 ug/L (MW-1) 6 ug/L n-Propylbenzene 157 ug/L (MW-1) 70 ug/L 1,2,4-Trimethylbenzene 1,310 ug/L (MW-1) 400 ug/L 1,3,5-Trimethylbenzene 440 ug/L (MW-1) 400 ug/L MTBE 554 ug/L (MW-1) 20 ug/L 4. Extent of Dissolved Groundwater Contamination: The plume of dissolved groundwater contamination has stabilized at its current extent. Historically, the plume was centered on the source area around the former dispenser island. In the past, the plume has extended under the former building with MW-9 containing 2L violations. Currently, RW-1 is the only remaining monitor well with significant 2L violations. The contaminant concentrations in RW-1 were at historical low concentrations in December of 2016; however, the concentrations in RW-1 have increased since the cessation of active remediation. 5. Maximum Soil Contaminant Concentrations (Soil samples collected after soil excavation on September 14, 2011): Contaminant Result Sample ID Lowest MSCC Benzene 0.147 mg/kg (PB#1) 0.0056 mg/kg p-Isopropyltoluene 0.539 mg/kg (PB#2) 0.12 mg/kg Naphthalene 3.12 mg/kg (PB#2) 0.16 mg/kg Xylenes (total) 5.3 mg/kg (PB#2) 4.6 mg/kg 2-Methylnaphthalene 6.09 mg/kg (PB#2) 3.6 mg/kg C9-C22 Aromatics 167.4 mg/kg (PB#2) 31 mg/kg 6. Remedial Action Plan: The approved Corrective Action Plan for this site stipulated active remediation through Mobile Multi-Phase Extraction (MMPE). Since the implementation of the Corrective Plan, there have been nine week-long MMPE events conducted between 2012 and 2018. This remedial strategy has been effective at reducing contaminant concentrations in the impacted monitor wells on site and reducing the overall extent of the dissolved groundwater contaminant plume. There was no measurable amount of free product in any well during the most recent sampling event. The contaminant concentrations in RW-1 were significantly below the historical maximum concentrations during the most recent sampling event. 7. Impacted Receptors: The supply wells within 1,000’ of the petroleum release source area have never been impacted by this release and are not considered to be at imminent risk of impact by this release. TABLE OF CONTENTS Section Page 1.0 Site History and Characterization 1.1 Introduction .................................................................... 1 1.2 Scope of Services ........................................................... 1 2.0 Presentation of Current Site Assessment Information / Comparison to Historical Assessment Information 2.1 Historical Assessment Information ................................ 2 2.2 Groundwater Flow Direction and Gradient ................... 3 2.3 Monitor Well Sampling and Analyses ........................... 3 2.4 Regional / Site Geology and Hydrogeology .................. 4 2.5 Plume Development ....................................................... 5 3.0 Monitored Natural Attenuation 3.1 Natural Source Zone Depletion Status ........................... 5 4.0 Conclusions 4.1 General Summary .......................................................... 6 4.2 Recommendations .......................................................... 6 4.3 Limitations ..................................................................... 6 5.0 Statements and Certification 5.1 Statements ...................................................................... 7 5.2 Certification ................................................................... 7 LIST OF FIGURES Figure 1: Project Location Figure 2: Site Layout and Former UST System Figure 3: Soil Concentrations Map Figure 3A: Soil Cross-Sections A to A’ and B to B’ Figure 3B: Remedial Excavation and Soil Sample Locations Figure 4: Potentiometric Surface Map (10/15/20) Figure 5: Groundwater Analytical Results Map Figure 6: Shallow Well Benzene Isoconcentration Map Figure 7: Shallow Well Naphthalene Isoconcentration Map Figure 8: Shallow Well MTBE Isoconcentration Map Figure 9: Supply Well Locations Map LIST OF TABLES Table 1: Site History Table 2: Water Supply Well Information Table 3: Summary of Soil Analytical Results Table 4: Summary of Groundwater Analytical Results Table 5: Evaluation of Change in Contaminant Mass Table 5A: Contaminant Mass Calculation Data Table 6: Monitoring Well Information and Groundwater Elevations APPENDICES Appendix A: Historical Sampling Results Appendix B: Contaminant Concentrations vs. Time Graphs Appendix C: Compilation of Costs / Chronology of Remediation Activities Appendix D: Proposed Remediation Schedule from Corrective Action Plan Appendix E: Laboratory Analytical Results Page - 1 GROUNDWATER MONITORING REPORT Northwest Superette 1014 NC Highway 68 N Oak Ridge, North Carolina 1.0 Site History and Characterization 1.1 Introduction Willyn, Inc. formerly operated a facility referred to as Northwest Superette which is located at 1014 NC Highway 68 N. in Oak Ridge, NC. The facility was in operation as a gas station and convenience store but in September of 2011 the NC Department of Transportation (NCDOT) purchased the land and demolished the building for the widening of NC Highway 68. The location of the project site is illustrated on the partial Summerfield Quadrangle U.S.G.S. Topographic Map which is included as Figure 1. One 6,000 gallon diesel underground storage tank (UST), two 6,000 gallon gasoline USTs, one 10,000 gallon gasoline UST, and one 1,000 gallon kerosene UST were formerly located at this location. The site layout and the former UST locations are illustrated on Figure 2. A UST Closure, 20 Day, and Initial Abatement Action Report was submitted by Paragon Environmental Consultants, Inc. on June 3, 2008. A Phase I and II Limited Site Assessment for Northwest Superette was prepared by Paragon Environmental Consultants, Inc. and was submitted to the NCDEQ on October 17, 2008. A Comprehensive Site Assessment for this facility was submitted to the NCDEQ on August 14, 2009, and a Pre-CAP monitoring report was submitted to the NCDEQ on October 20, 2010. A Corrective Action Plan was submitted to NCDEQ by Paragon Environmental Consultants, Inc. on March 16, 2011. Active Remediation Monitoring Reports for this facility were submitted to NCDEQ on December 28, 2011, May 18, 2012, August 8, 2013, December 26, 2013, July 8, 2014, January 18, 2016, July 19, 2016 and December 23, 2016. Groundwater Monitoring Reports for this facility were prepared by Paragon and submitted to the UST Section on July 26, 2017 and May 21, 2018. The site has been ranked as High Risk based on supply wells in use for consumption. Figure 9 illustrates the locations of the supply wells in the immediate vicinity of the Northwest Superette site. The monitor wells which are currently present at 1014 NC Highway 68 N, as well as the wells which were destroyed by the NCDOT, are depicted on Figure 5. Contained herein are the results of a groundwater sampling event as directed by the NCDEQ. 1.2 Scope of Services Contained herein are the results of a groundwater sampling event as approved by the NCDEQ in an approved TAF dated August 20, 2020. This Groundwater Monitoring Report contains documentation concerning the following activities which have been conducted at this facility: o Sampling of four monitor wells conducted by Paragon on October 15, 2020. o Laboratory analyses of groundwater samples by Meritech, Inc. of Reidsville, NC. o The approximate groundwater flow direction and hydraulic gradient at the site calculated by Paragon. Page - 2 2.0 Presentation of Current Site Assessment Information / Comparison to Historical Assessment Information 2.1 Historical Assessment Information On May 15, 2008, a release was confirmed by assessment soil sampling conducted during the removal of the UST system at this facility on May 6 and May 7, 2008. Between May 8 and May 13, 2008, approximately 683.29 tons of petroleum impacted soils were excavated during the Initial Abatement Action activities. “Risk-Based” soil samples collected from the limits of the remedial excavation indicated petroleum contaminant concentrations in excess of the lowest Maximum Soil Contaminant Concentrations (MSCCs). Four additional soil borings were advanced to depths of 15 feet during the CSA activities. All four of these samples contained Benzene at levels above the lowest MSCC of 0.0056 milligrams per kilogram (mg/kg). All of the other compounds in these four samples were below the lowest MSCCs by EPA Methods 8260 and 8270, as well as Volatile Petroleum Hydrocarbons (VPH) and Extractable Petroleum Hydrocarbons (EPH). An attempt to remediate the remaining gasoline and kerosene impacted soils was made through excavation on September 12, 13, and 14, 2011 by KBS Earthworks and Paragon. Since the previous excavation activities in the areas of the former USTs and the kerosene dispenser island, the NC Department of Transportation has purchased the subject property and demolished the structure of the former store building and the two canopies. This allowed the further excavation of contaminated soils from beneath the former kerosene dispenser and the gasoline dispenser island. KBS Earthworks excavated approximately 599 cubic yards (897.83 tons) of soil contamination from the project site between September 12 and 14, 2011. The soils in the contaminated zone were excavated in the horizontal directions until field analyses indicated all petroleum contaminated soil had been removed. The petroleum impacted soils were also removed to the vertical limit of the track-hoe being utilized for the soil removal at a depth of approximately 21 feet. In order to verify site conditions, two samples were collected from the pit bottom at a depth of approximately 21 feet and six samples were collected from the side walls at approximately 19 feet below grade. The samples from the pit bottom of the remedial excavation showed several concentrations of Method 8260 and 8270 compounds which were above the lowest MSCCs. Sample PB-2 showed Naphthalene at 3.12 mg/kg which exceeds the lowest MSCC of 0.16 mg/kg. Xylenes were reported at 5.30 mg/kg in sample PB-2 as compared to the lowest MSCC of 4.6 mg/kg. 2-Methylnapthalene, which has a lowest MSCC of 3.6 mg/kg, was detected at 6.09 mg/kg. C9-C22 Aromatics was listed at 167.4 mg/kg which exceeds the lowest MSCC of 31 mg/kg. PB-2 also contained seven other Method 8260 compounds and two Aliphatic fraction classes above the laboratory detection limits but below the lowest MSCCs. Sample PB-1 showed Benzene at a concentration of 0.147 mg/kg which is in excess of the lowest MSCC of 0.0056 mg/kg. All of the other compounds and fraction classes in this sample were below the lowest MSCCs. All six of the wall samples from the remedial pit were below laboratory detection limits by EPA Methods 8260 and 8270 as well as VPH and EPH. Based on this data for the soil samples, the remaining contaminated soils are situated in the below the former pit bottom of the remedial excavation conducted in the vicinity of the gasoline dispenser island. Figure 3 illustrates the soil sample locations and the extent of the soil excavation conducted in 2008 at the Northwest Superette facility. Figure 3A depicts the soil samples and the contaminant levels in cross-sections A to A’ and B to B’. Figure 3B depicts the soil sample locations and the extent of soil excavation conducted in 2011 at the Northwest Superette facility. The results for the “Risk-Based” soil samples obtained at the subject property are summarized in Table 3. Page - 3 2.2 Ground Water Flow Direction and Gradient In order to estimate the groundwater flow direction in the vicinity of the petroleum release, elevations of the monitor well casings were measured using surveying equipment. Static water levels were obtained from monitor wells RW-1, MW-2, MW-7, and MW-10 and the data was used to compute a potentiometric surface map. Figure 4 illustrates the current potentiometric surface map as calculated based on the measurements obtained on October 15, 2020. Table 6 contains the groundwater elevation data and monitoring well information. Groundwater data and monitoring well information were also used to estimate the hydraulic gradient at the project site. Using the horizontal distance between the monitor wells and the static water levels, the groundwater was calculated to flow toward the southeast with a hydraulic gradient of approximately 0.00435 feet per feet. 2.3 Monitor Well Sampling and Analyses On October 15, 2020, RW-1, MW-2, MW-7, and MW-10 on the Northwest Superette property were sampled and the samples submitted to Meritech, Inc. for analyses utilizing EPA Method 6200B plus MTBE and IPE. Before collecting the samples, the monitor wells were purged by removing a minimum of three well volumes to ensure that the samples were representative of the actual groundwater conditions. The wells were developed using disposable plastic bailers suspended with unused nylon string. Following development of the monitoring wells, groundwater samples were obtained from the disposable bailers. All samples were placed in laboratory supplied glassware, labeled with sample location, analysis to be performed, time, date, and sampler's name. The sample jars were then immediately placed in a cooler and chilled with ice to approximately 4oC in preparation for transportation to the analytical laboratory utilizing EPA approved chain-of-custody procedures. The analytical results for the sample collected from recovery well RW-1 on October 15, 2020 reported eight EPA Method 6200B compounds at concentrations above the 2L Standards. Benzene was detected at a concentration of 1,290 micrograms per Liter (ug/L), which is over the 2L Standard of 1 ug/L. Toluene was listed at a level of 4,220 ug/L, which exceeds the 2L Standard of 600 ug/L. Ethylbenzene was shown at a concentration of 731 ug/L, in excess of the 2L Standard of 600 ug/L. Xylenes were reported at a total concentration of 5,620 ug/L, which is over the 2L Standard of 500 ug/L. Isopropylbenzene, which has a 2L Standard of 70 ug/L, was listed at a level of 76 ug/L. Naphthalene was indicated at level of 300 ug/L, which exceeds the 2L Standard of 6 ug/L. n-Propylbenzene was reported at a concentration of 157 ug/L, as compared to the 2L Standard of 70 ug/L. 1,2,4-Trimethylbenzene was listed at 1,310 ug/L, which is in excess of the 2L Standard of 400 ug/L. 1,3,5-Trimethylbenzene was reported at a concentration of 440 ug/L, which is over the 2L Standard of 400 ug/L. MTBE, which has a 2L Standard of 20 ug/L, was reported at a concentration of 554 ug/L. All other compounds were below the laboratory detection limits in RW-1 according to EPA Method 6200B. Monitor well MW-7 contained MTBE at a level of 35.9 ug/L. All other compounds were below the 2L Standards in MW-7 according to EPA Method 6200B. Monitor wells MW-2 and MW-10 were below the laboratory detection limits for all analyzed compounds at the Northwest Superette according to EPA Method 6200B. Page - 4 Table 4 summarizes the groundwater analytical results from the sampling events conducted on October 15, 2020. Figure 5 illustrates the groundwater analytical results from the sampling event conducted on October 15, 2020. Figure 6 illustrates the estimated horizontal extent of Benzene in the groundwater on an isoconcentration map. Figure 7 illustrates the estimated horizontal extent of Naphthalene in the groundwater on an isoconcentration map. Figure 8 illustrates the estimated extent of MTBE in the groundwater on an isoconcentration map. Appendix E contains copies of the laboratory reports and the chain-of-custody records for the groundwater samples obtained on October 15, 2020. 2.4 Regional / Site Geology and Hydrogeology The site is situated in the Piedmont Region of the North Carolina Slate Belt. According to the Geological Map of North Carolina, local bedrock geology of the region consists of Late Proterozoic to Cambrian aged metamorphosed granite bedrock. The shallow groundwater table is situated between 19 and 22 feet below land surface as measured in the monitor wells on October 15, 2020. The locations of the shallow monitor wells are illustrated in plan view on Figure 5. Competent bedrock was encountered at a depth of 46 feet during the installation of the vertical extent well at this facility. The soils encountered at the project site consisted predominantly of silt with varying amounts of clay. Field observations showed the soils at the site consist of a variety of textural assemblages as noted: o red-brown to tan silt with varying clay content o orange-brown to brown silt with varying clay content o olive-brown to olive-tan silt with varying clay content Groundwater is noted to be flowing in a predominantly southeastern direction according to the data collected on October 15, 2020. The average potentiometric surface gradient has been calculated at approximately 0.00435 feet per feet. During the CSA hydrogeological investigation, two single well rising head tests or "slug tests" were performed on MW-2 and MW-3 to determine the saturated hydraulic conductivity of the water table aquifer. The method of Bouwer and Rice (Bouwer and Rice, 1989, 1976) was chosen to reduce the slug test data. A computer program developed by the Geraghty & Miller Modeling Group named Aqtesolv was used to estimate the aquifer parameters. Results of the slug tests indicated hydraulic conductivities of 8.322 x 10-4 feet/minute in MW-2 and 7.313 x 10-4 feet/minute in MW-3. These results are consistent with published values for silt, loess, and silty sand (Freeze & Cherry, 1979). Groundwater flow velocity was determined by averaging the hydraulic conductivity values and assuming an estimated effective porosity of 20% for soils at the site. The following equation yields an estimate of average groundwater flow velocity: v = k/n x dh/dl Where v = average groundwater flow velocity k = average hydraulic conductivity = 7.818 x 10-4 ft/min. Page - 5 n = effective porosity = 0.20 dh/dl = groundwater head gradient = 0.00435 ft/ft The average groundwater flow velocity at the Northwest Superette site has been calculated to be approximately 1.7 x 10-5 feet per minute which would equal 8.94 feet per year. 2.5 Plume Development Historically, the plume was centered on the source area around the former dispenser island. In the past, the plume has extended under the former building with MW-9 containing 2L violations. Currently, RW-1 is the only remaining monitor well with significant 2L violations. The contaminant concentrations in RW-1 were at historical low concentrations in December of 2016; however, the concentrations in RW-1 have increased since the cessation of active remediation. The historical maximum contaminant mass was calculated from the data collected at the time of the Corrective Action Plan to be approximately 4,236.11 kilograms (kg). The current contaminant mass calculated after the most recent sampling event on October 15, 2020 was approximately 15.08 kg. An arbitrary milestone of 5% contaminant mass reduction per MMPE event was chosen since the Corrective Action Plan for this site was prepared in 2011 and implemented before the 2020 RRD. These cleanup goals have been met in the remediation events conducted since the approval of the Corrective Action Plan. The target cleanup goal is to remediate the dissolved phase groundwater contamination to concentrations below the 2L Standards, which would make the site eligible for closure. Alternate standards of 50 ug/L for Benzene and 200 ug/L for MTBE were proposed in the approved Corrective Action Plan. These target cleanup goals have yet to be achieved. Table 5 contains the evaluation of change in contaminant mass and Table 5A contains the contaminant mass calculation data. Appendix A contains the historical sampling results for the monitor and recovery wells at the subject site. Appendix B contains graphs depicting the contaminant concentrations vs. time for Benzene, Naphthalene, and MTBE. Appendix C contains a compilation of costs and a chronology of remediation activities. Appendix D contains the proposed remediation schedule from the approved CAP. 3.0 Monitored Natural Attenuation 3.1 Natural Source Zone Depletion Status No active remediation has been conducted at this site since 2018. The contaminant concentrations in the most highly impacted well (RW-1) have increased since the previous sampling event conducted on March 15, 2018, shortly after the most recent MMPE event. The other impacted monitor well which remains on-site (MW-7) has decreased significantly in MTBE concentration since the previous sampling event conducted on March 15, 2018, shortly after the most recent MMPE event. Natural attenuation seems to be steadily reducing the contaminant concentrations in the perimeter wells, but not in the source area well. The plume has stabilized and is apparently contracting in size. There are currently only two remaining monitor wells with 2L Violations. It appears that the majority of petroleum contaminant mass has been removed during the two soil excavations conducted in 2008 and 2011 to allow the plume to contract in size, but enough contaminant mass remains to prevent significant natural attenuation in the source area well. Page - 6 4.0 Conclusions 4.1 General Summary A Groundwater Monitoring event at Northwest Superette located at 1014 NC Highway 68 N. in Oak Ridge, NC has been completed. From a review of all information gathered during this monitoring project, Paragon Environmental Consultants, Inc. makes the following conclusions: o Ten EPA Method 6200B compounds exceeding the 2L Standards were present in the source area (RW-1) during the October 15, 2020 sampling event. Monitor well MW-7 also showed MTBE slightly in excess of the 2L Standard according to EPA Method 6200B. o Contaminant mass removal calculations show that the site was being steadily remediated to the target cleanup goals and that the arbitrary milestones of 5% reduction in contaminant mass per week-long MMPE event were being met before the cessation of active remediation in 2018. 4.2 Recommendations Paragon recommends that periodic groundwater monitoring should be continued at Northwest Superette. A copy of this monitoring report should be forwarded to the following address: Guilford County Health Department 400 W. Market Street – Suite 300 Greensboro, NC 27401 4.3 Limitations This report has been prepared for the exclusive use of Willyn, Inc. for the specific application to the referenced site located in Guilford County, North Carolina. The assessment was conducted based on the scope of work and level of effort desired by the client. Our findings have been developed in accordance with generally accepted standards in the practice of Groundwater Monitoring 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 that existed at the precise locations sampled and at the time the samples were collected. Additionally, the data obtained from the samples would be interpreted as meaningful with respect to the parameters indicated in the laboratory reports. No additional information can be logically inferred from this data. Page - 7 5.0 Statements and Certification 5.1 Statements The monitoring report had no established due date. Will this report be submitted after the established due date? No Was any required information from the template missing from this report? No If applicable, will any of the proposed attenuation milestones under the schedule approved in the Corrective Action Plan not be met? No Does any known or suspected source zone soil contamination or free product remain outside of the assessed area that could be inhibiting natural attenuation? No Has there been an unexpected increase in contaminant mass sufficient to suggest a potential new release from a separate onsite or offsite source? No 5.2 Certification I, Benjamin W. Robinson, a Licensed Geologist for Paragon Environmental Consultants, Inc., do certify that the information contained in this report is correct and accurate to the best of my knowledge. Benjamin W. Robinson, L.G. North Carolina License #2466 Paragon Environmental Consultants, Inc. is licensed to practice geology in North Carolina. The certification number of the corporation is C-300. FIGURES TABLES TABLE 1: SITE HISTORY NORTHWEST SUPERETTE 1014 NC HIGHWAY 68 N. OAK RIDGE, NORTH CAROLINA Property Ownership: NC Department of Transportation P. O. Box 14996 Greensboro, NC 27415 UST Ownership: Willyn, Inc. 8531 NC Highway 49 S. Snow Camp, NC 27349-9210 UST Information: Tank Installation Size Closure UST Tank No Date (Gal) Date Status Contents T1 5/7/1978 6,000 5/7/2008 Removed Diesel T2 5/7/1978 6,000 5/7/2008 Removed Gasoline T3 5/7/1978 6,000 5/7/2008 Removed Gasoline T4 5/7/1978 1,000 5/7/2008 Removed Kerosene T5 5/6/1981 10,000 5/7/2008 Removed Gasoline M20-818H TABLE 2 Northwest Superette Oak Ridge, North Carolina Well Identification SW-1 SW-2 SW-3 SW-4 SW-5 Owner Name NCDOT Sacks Family Properties, LLC Cindy A. Jones Everett Family Living Trust Simaan, Inc. Owner Address P.O. Box 14996 P.O. Box 579 3307 Edgefied Road 1187 Farm Quarter Road P.O. Box 549 Greensboro, NC 27415 Oak Ridge, NC 27310 Greensboro, NC 27409 Mount Pleasant, SC 29464 Summerfield, NC 27358 Telephone #(336) 334-3228 Unknown Unknown Unknown (336) 643-9966 Use of Well Out Of Service Consumption Consumption Consumption Consumption Depth of Well Unknown Unknown Unknown Unknown Unknown Type of Well Unknown Unknown Unknown Unknown Unknown Well Yield Unknown Unknown Unknown Unknown Unknown Depth of Casing Unknown Unknown Unknown Unknown Unknown Well Screen Interval Unknown Unknown Unknown Unknown Unknown Feet from Source 130'390'395'400'415' X20-818C WATER SUPPLY WELL INFORMATION 1,500' RADIUS TABLE 2 (CONT'D) Northwest Superette Oak Ridge, North Carolina Well Identification SW-6 SW-7 SW-8 SW-9 SW-10 Owner Name Leasure Properties III, LLC Bel-Aire Veterinary Hospital 3323 Edgefield Road, LLC Epes Transport System, LLC Freddie and Melinda Marshall Owner Address 3410 Edgefield Court 7712 Kenmont Road 8423 Mears Fork Road 3400 Edgefield Court 3400 Edgefield Road Greensboro, NC 27409 Greensboro, NC 27409 Summerfield, NC 27358 Greensboro, NC 27408 Greensboro, NC 27409 Telephone #Unknown Unknown Unknown Unknown (336) 643-9966 Use of Well Consumption Consumption Consumption Consumption Consumption Depth of Well Unknown Unknown Unknown Unknown Unknown Type of Well Unknown Unknown Unknown Unknown Unknown Well Yield Unknown Unknown Unknown Unknown Unknown Depth of Casing Unknown Unknown Unknown Unknown Unknown Well Screen Interval Unknown Unknown Unknown Unknown Unknown Feet from Source 540'575'960'1,045'1,115' X20-818C WATER SUPPLY WELL INFORMATION (CONT'D) 1,500' RADIUS TABLE 2 (CONT'D) Northwest Superette Oak Ridge, North Carolina Well Identification SW-11 SW-12 Owner Name Hisako S. Schneider Jeffrey D. Richardson Owner Address 4506 Fence Drive 4505 Fence Drive Greensboro, NC 27409 Greensboro, NC 27409 Telephone #Unknown Unknown Use of Well Consumption Consumption Depth of Well Unknown Unknown Type of Well Unknown Unknown Well Yield Unknown Unknown Depth of Casing Unknown Unknown Well Screen Interval Unknown Unknown Feet from Source 1,380'1,400' X20-818C WATER SUPPLY WELL INFORMATION (CONT'D) 1,500' RADIUS TABLE 3 Summary of Soil Analytical Results Northwest Superette Oak Ridge, North Carolina Constituent EW WW NPB MPB SPB Lowest MSCC Date 5/12/2008 5/12/2008 5/12/2008 5/12/2008 5/12/2008 Method 8260 (mg/kg) Benzene 17.7 0.055 BDL 4.4 0.009 0.0056 n-Butylbenzene 72.8 BDL BDL 14.1 BDL 4.3 sec-Butylbenzene BDL BDL 0.742 5.65 BDL 3.3 Ethylbenzene 195 0.018 2.18 62.5 BDL 4.9 Isopropylbenzene 31 BDL 0.53 10.2 BDL 1.7 p-Isopropyltoluene BDL 0.005 BDL BDL BDL 0.12 Naphthalene BDL BDL BDL BDL BDL 0.16 n-Propylbenzene 109 0.006 1.55 37.8 BDL 1.7 1,2,4-Trimethylbenzene 432 0.075 10.4 180 BDL 8.5 1,3,5-Trimethylbenzene 160 0.025 4.91 59.9 BDL 8.3 Toluene 248 0.119 2.11 92.4 0.01 4.3 Xylenes (total)836 0.162 15.89 323 BDL 4.6 IPE BDL BDL BDL BDL BDL 0.37 MTBE BDL 0.393 BDL BDL 0.056 0.091 Method 8270 (mg/kg) Acenaphthene BDL BDL BDL BDL BDL 8.2 2-Methylnaphthalene 70.9 BDL BDL 19.8 BDL 3.6 Naphthalene 76.1 BDL BDL 21.4 BDL 0.16 Phenanthrene BDL BDL BDL BDL BDL 56 Aliphatic Fraction Classes (mg/kg) C5-C8 Volatile Aliphatics 2,430 BDL 67.5 628 BDL 68 C9-C12 Volatile Aliphatics 7,350 BDL 495 2,090 BDL NSE C9-C18 Extractable Aliphatics 1,220 BDL 2,050 200 BDL 540 C9-C18 Aliphatics (total)8,570 BDL 2,545 2,290 BDL 540 C19-C36 Extractable Aliphatics BDL BDL 677 BDL BDL 31,000 Aromatic Fraction Classes (mg/kg) C9-C10 Volatile Aromatics 3,880 BDL 232 1,090 BDL NSE C11-C22 Extractable Aromatics 582 BDL 1,380 204 BDL NSE C9-C22 Aromatics (total)4,462 BDL 1,612 1,294 BDL 31 BDL = Below Detection Limits N/A = Not Analyzed NSE = No Standard Established X20-818 TABLE 3 (CONT'D) Summary of Soil Analytical Results (Cont'd) Northwest Superette Oak Ridge, North Carolina Constituent KPB T1N-PB MW1-10 MW1-20 Lowest MSCC Date 5/13/2008 5/13/2008 5/13/2008 5/13/2008 Method 8260 (mg/kg) Benzene 0.283 BDL BDL 2.31 0.0056 n-Butylbenzene 1.45 BDL 2.98 11.7 4.3 sec-Butylbenzene 0.663 BDL 1.02 4.34 3.3 Ethylbenzene 3.94 BDL 3.93 42.7 4.9 Isopropylbenzene 0.791 BDL 1.12 7.21 1.7 p-Isopropyltoluene 0.962 BDL 1.59 2.03 0.12 Naphthalene 0.888 0.02 7.88 27.1 0.16 n-Propylbenzene 2.78 BDL 4.61 26.4 1.7 1,2,4-Trimethylbenzene 14.4 BDL 26.6 132 8.5 1,3,5-Trimethylbenzene 4.97 BDL 8.33 42.3 8.3 Toluene 5.06 BDL 2.58 63.1 4.3 Xylenes (total)23.02 BDL 23.55 209.9 4.6 IPE N/A N/A BDL BDL 0.37 MTBE N/A N/A BDL BDL 0.091 Method 8270 (mg/kg) Acenaphthene BDL BDL BDL BDL 8.2 2-Methylnaphthalene BDL BDL 3.02 9.55 3.6 Naphthalene BDL BDL 4.1 17.2 0.16 Phenanthrene BDL BDL BDL BDL 56 Aliphatic Fraction Classes (mg/kg) C5-C8 Volatile Aliphatics BDL BDL 54.1 615 68 C9-C12 Volatile Aliphatics BDL BDL 169 1,470 NSE C9-C18 Extractable Aliphatics 423 BDL 53.3 414 540 C9-C18 Aliphatics (total)423 BDL 222.3 1,884 540 C19-C36 Extractable Aliphatics BDL BDL BDL BDL 31,000 Aromatic Fraction Classes (mg/kg) C9-C10 Volatile Aromatics BDL BDL 101 738 NSE C11-C22 Extractable Aromatics 73.3 BDL 33.7 164 NSE C9-C22 Aromatics (total)73.3 BDL 134.7 902 31 BDL = Below Detection Limits N/A = Not Analyzed NSE = No Standard Established X20-818 TABLE 3 (CONT'D) Summary of Soil Analytical Results (Cont'd) Northwest Superette Oak Ridge, North Carolina Constituent GP-1 GP-2 GP-3 GP-4 Lowest MSCC's Date 4/3/2009 4/3/2009 4/3/2009 4/3/2009 Method 8260 (mg/kg) Benzene 0.007 0.023 0.006 0.032 0.0056 n-Butylbenzene BDL BDL BDL BDL 4.3 sec-Butylbenzene BDL BDL BDL BDL 3.3 tert-Butylbenzene BDL BDL BDL BDL 3.4 Ethylbenzene BDL BDL BDL BDL 4.9 Isopropylbenzene BDL BDL BDL BDL 1.7 p-Isopropyltoluene BDL BDL BDL BDL 0.12 Naphthalene BDL BDL BDL BDL 0.16 n-Propylbenzene BDL BDL BDL BDL 1.7 1,2,4-Trimethylbenzene BDL 0.005 BDL BDL 8.5 1,3,5-Trimethylbenzene BDL BDL BDL BDL 8.3 Toluene 0.007 0.020 BDL 0.035 4.3 Xylenes (total)BDL 0.017 BDL 0.019 4.6 IPE BDL BDL BDL BDL 0.37 MTBE 0.253 0.127 BDL BDL 0.091 Method 8270 (mg/kg) Acenaphthene BDL BDL BDL BDL 8.2 2-Methylnaphthalene BDL BDL BDL BDL 3.6 Naphthalene BDL BDL BDL BDL 0.16 Phenanthrene BDL BDL BDL BDL 56 Aliphatic Fraction Classes (mg/kg) C5-C8 Volatile Aliphatics BDL BDL BDL BDL 68 C9-C12 Volatile Aliphatics BDL BDL BDL BDL NSE C9-C18 Extractable Aliphatics BDL BDL BDL BDL 540 C9-C18 Aliphatics (total)BDL BDL BDL BDL 540 C19-C36 Extractable Aliphatics BDL BDL BDL BDL NSE Aromatic Fraction Classes (mg/kg) C9-C10 Volatile Aromatics BDL BDL BDL BDL NSE C11-C22 Extractable Aromatics BDL BDL BDL BDL NSE C9-C22 Aromatics (total)BDL BDL BDL BDL 31 BDL= Below Detection Limits NSE = No Standard Established X20-818 TABLE 3 (CONT'D) Summary of Soil Analytical Results (Cont'd) Northwest Superette Oak Ridge, North Carolina Constituent NW SW EW#1 EW#2 Lowest MSCCs Date 9/13/2011 9/14/2011 9/13/2011 9/14/2011 Method 8260 (mg/kg) n-Butylbenzene BDL BDL BDL BDL 4.3 sec-Butylbenzene BDL BDL BDL BDL 3.3 tert-Butylbenzene BDL BDL BDL BDL 3.4 Ethylbenzene BDL BDL BDL BDL 4.9 Isopropylbenzene BDL BDL BDL BDL 1.7 p-Isopropyltoluene BDL BDL BDL BDL 0.12 Naphthalene BDL BDL BDL BDL 0.16 n-Propylbenzene BDL BDL BDL BDL 1.7 1,2,4-Trimethylbenzene BDL BDL BDL BDL 8.5 1,3,5-Trimethylbenzene BDL BDL BDL BDL 8.3 Toluene BDL BDL BDL BDL 4.3 Xylenes (total)BDL BDL BDL BDL 4.6 Method 8270 (mg/kg) Acenaphthene BDL BDL BDL BDL 8.2 Bis(2-ethylhexyl)phthalate BDL BDL BDL BDL 3 Fluorene BDL BDL BDL BDL 47 2-Methylnaphthalene BDL BDL BDL BDL 3.6 Naphthalene BDL BDL BDL BDL 0.16 Phenanthrene BDL BDL BDL BDL 56 Pyrene BDL BDL BDL BDL 270 Aliphatic Fraction Classes (mg/kg) C5-C8 Volatile Aliphatics BDL BDL BDL BDL 68 C9-C12 Volatile Aliphatics BDL BDL BDL BDL NSE C9-C18 Extractable Aliphatics BDL BDL BDL BDL 540 C9-C18 Aliphatics (total)BDL BDL BDL BDL 540 C19-C36 Extractable Aliphatics BDL BDL BDL BDL NSE Aromatic Fraction Classes (mg/kg) C9-C10 Volatile Aromatics BDL BDL BDL BDL NSE C11-C22 Extractable Aromatics BDL BDL BDL BDL NSE C9-C22 Aromatics (total)BDL BDL BDL BDL 31 BDL= Below Detection Limits NSE = No Standard Established X20-818 TABLE 3 (CONT'D) Summary of Soil Analytical Results (Cont'd) Northwest Superette Oak Ridge, North Carolina Constituent WW#1 WW#2 PB#1 PB#2 Lowest MSCCs Date 9/14/2011 9/14/2011 9/13/2011 9/14/2011 Method 8260 (mg/kg) Benzene BDL BDL 0.147 BDL 0.0056 n-Butylbenzene BDL BDL 0.006 0.592 4.3 sec-Butylbenzene BDL BDL BDL BDL 3.3 tert-Butylbenzene BDL BDL BDL BDL 3.4 Ethylbenzene BDL BDL 0.069 0.555 4.9 Isopropylbenzene BDL BDL 0.006 BDL 1.7 p-Isopropyltoluene BDL BDL BDL 0.539 0.12 Naphthalene 0.006 BDL BDL 3.12 0.16 n-Propylbenzene BDL BDL 0.016 0.515 1.7 1,2,4-Trimethylbenzene BDL BDL 0.067 8.04 8.5 1,3,5-Trimethylbenzene BDL BDL 0.015 2.68 8.3 Toluene BDL BDL 0.518 0.912 4.3 Xylenes (total)BDL BDL 0.461 5.30 4.6 Method 8270 (mg/kg) Acenaphthene BDL BDL BDL BDL 8.2 Bis(2-ethylhexyl)phthalate BDL BDL BDL BDL 3 Fluorene BDL BDL BDL BDL 47 2-Methylnaphthalene BDL BDL BDL 6.09 3.6 Naphthalene BDL BDL BDL BDL 0.16 Phenanthrene BDL BDL BDL BDL 56 Pyrene BDL BDL BDL BDL 270 Aliphatic Fraction Classes (mg/kg) C5-C8 Volatile Aliphatics BDL BDL 5.78 17.6 68 C9-C12 Volatile Aliphatics BDL BDL 6.98 191 NSE C9-C18 Extractable Aliphatics BDL BDL BDL 105 540 C9-C18 Aliphatics (total)BDL BDL 6.98 296 540 C19-C36 Extractable Aliphatics BDL BDL BDL BDL NSE Aromatic Fraction Classes (mg/kg) C9-C10 Volatile Aromatics BDL BDL BDL 106 NSE C11-C22 Extractable Aromatics BDL BDL BDL 61.4 NSE C9-C22 Aromatics (total)BDL BDL BDL 167.4 31 BDL= Below Detection Limits NSE = No Standard Established X20-818 TABLE 4 Summary of Groundwater Analytical Results Northwest Superette Oak Ridge, North Carolina Constituent RW-1 MW-2 MW-7 MW-10 2L Standard Date 10/15/2020 10/15/2020 10/15/2020 10/15/2020 EPA Method 6200B (ug/L) Benzene 1,290 BDL BDL BDL 1 Toluene 4,220 BDL BDL BDL 600 Ethylbenzene 731 BDL BDL BDL 600 Xylenes (total)5,620 BDL BDL BDL 500 BTEX (total)11,861 BDL BDL BDL NSE Bromodichloromethane BDL BDL BDL BDL 0.6 Chloroform BDL BDL 2.52 BDL 70 Dibromochloromethane BDL BDL BDL BDL 0.4 2-Hexanone BDL BDL BDL BDL 40 1,2-Dichloropropane BDL BDL BDL BDL 0.6 Isopropylbenzene 76 BDL BDL BDL 70 Methylene Chloride BDL BDL BDL BDL 5 Naphthalene 300 BDL BDL BDL 6 n-Propylbenzene 157 BDL BDL BDL 70 1,2,4-Trimethylbenzene 1,310 BDL BDL BDL 400 1,3,5-Trimethylbenzene 440 BDL BDL BDL 400 IPE BDL BDL BDL BDL 70 MTBE 554 BDL 35.9 BDL 20 BDL = Below Detection Limits NSE = No Standard Established X20-818A TABLE 5 Evaluation of Change in Contaminant Mass Northwest Superette Oak Ridge, NC Mass Estimates Baseline 12/1/11 5/3/12 2/21/13 7/19/13 11/21/13 6/3/14 12/21/15 7/1/16 12/12/16 6/22/17 3/15/18 10/15/20 Projected Mass Reduction:0%5%10%15%20%25%30%35%40%45%50%55%60% Soil Source Zone Mass:4,144.91 3,937.66 3,730.42 3,523.17 3,315.93 3,108.68 2,901.44 2,694.19 2,486.95 2,279.70 2,072.46 1,865.21 1,657.96 Groundwater Zone Mass:91.20 86.64 82.08 77.52 72.96 68.40 63.84 59.28 54.72 50.16 45.60 41.04 36.48 Total Mass:4,236.11 4,024.30 3,812.50 3,600.69 3,388.89 3,177.08 2,965.28 2,753.47 2,541.67 2,329.86 2,118.06 1,906.25 1,694.44 Change in Contaminant Mass Measured Mass Soil Source Zone:4,144.91 120.38 Not Measured Not Measured Not Measured Not Measured Not Measured Not Measured Not Measured Not Measured Not Measured Not Measured Not Measured Groundwater Source Zone:91.20 40.74 39.96 11.55 10.45 3.71 5.95 23.54 34.33 1.90 5.32 9.06 17.36 Removed Mass Excavated from Soil:0.00 2,117.69 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Extracted as Vapor/Gas:0.00 0.00 151.37 751.27 48.82 41.67 39.16 25.24 14.47 22.00 7.37 27.14 0.00 Extracted as Liquid:0.00 0.00 0.38 0.15 0.16 0.06 0.08 0.37 0.54 0.04 0.09 0.17 0.00 Total Mass Removed:0.00 2,117.69 151.75 751.42 48.98 41.73 39.24 25.61 15.01 22.04 7.46 27.31 0.00 Revised Total Mass:4,236.11 2,118.42 1,966.67 1,215.25 1,166.28 1,124.55 1,085.31 1,059.69 1,044.69 1,022.65 1,015.19 987.88 987.88 Estimated Reduction Rate:0.00 49.99 7.16 38.21 4.03 3.58 3.49 2.36 1.42 2.11 0.73 2.69 0.00 Reference Milestone 0%5%10%15%20%25%30%35%40%45%50%55%60% Reference Milestone 4,236.11 4,024.30 3,812.50 3,600.69 3,388.89 3,177.08 2,965.28 2,753.47 2,541.67 2,329.86 2,118.06 1,906.25 1,694.44 Reduction Progress vs. Milestone 0.00 0.47 0.48 0.66 0.66 0.65 0.63 0.62 0.59 0.56 0.52 0.48 0.42 NOTE: Arbitrary milestones of 5% reduction per event were chosen as no milestones were required in format of the Corrective Action Plan approved in 2011. All results are reported in kilograms (kg)X20-818MRC Milestones TABLE 5A Contaminant Mass Calculation Data Northwest Superette Oak Ridge, NC Baseline 12/1/11 5/3/12 2/21/13 7/19/13 11/21/13 6/3/14 12/21/15 7/1/16 12/12/16 6/22/17 3/15/18 10/15/20 Soil Area (sq ft)1,509.88 1,721.22 Average Depth (ft)12.42 3.30 Volume (ft³)18,752.65 5,680.01 Volume (m³)531.02 160.84 Bulk Density (kg/m³)1,430.00 1,430.00 Soil Mass (kg)759,351.66 230,000.87 Avg. Conc. (mg/kg)5,458.49 523.40 Mass Cont. (kg)4,144.91 120.38 Groundwater Area (sq ft)29,575.12 19,627.40 23,477.80 18,302.27 18,269.33 16,235.49 19,056.34 18,299.96 17,135.81 12,074.23 15,831.15 15,701.92 10,262.95 Average Depth (ft)20.48 21.69 22.57 22.34 23.59 23.18 24.26 22.15 23.93 22.44 23.33 21.84 25.18 Volume (ft³)605,698.37 425,718.20 529,894.04 408,872.77 430,973.61 376,338.55 462,306.84 405,344.17 410,059.87 270,945.61 369,340.62 342,929.99 258,421.00 Volume (L)17,151,439.59 12,054,977.12 15,004,903.64 11,577,968.32 12,203,793.46 10,656,703.50 13,091,050.33 11,478,049.84 11,611,583.43 7,672,312.75 10,458,544.33 9,710,679.81 7,317,655.86 Porosity (n)0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20 Volume Water (L)3,430,287.92 2,410,995.42 3,000,980.73 2,315,593.66 2,440,758.69 2,131,340.70 2,618,210.07 2,295,609.97 2,322,316.69 1,534,462.55 2,091,708.87 1,942,135.96 1,463,531.17 Avg. Conc. (ug/L)26,586.50 16,897.00 13,316.50 4,990.00 4,281.25 1,740.50 2,273.38 10,255.00 14,782.00 1,235.53 2,541.35 4,664.24 11,861.00 Mass Cont. (kg)91.20 40.74 39.96 11.55 10.45 3.71 5.95 23.54 34.33 1.90 5.32 9.06 17.36 Extracted Water (L)0.00 0.00 28,806.97 29,374.78 36,589.77 34,625.15 35,632.06 36,230.16 36,729.83 31,558.96 35,170.24 36,567.06 0.00 Extracted Mass (kg)0.00 0.00 0.38 0.15 0.16 0.06 0.08 0.37 0.54 0.04 0.09 0.17 0.00 NOTE: Arbitrary milestones of 5% reduction per event were chosen as no milestones were required in format of the Corrective Action Plan approved in 2011. All results are reported in kilograms (kg)X20-818MRCD Milestones TABLE 6 Monitoring Well Information and Groundwater Elevations Northwest Superette Oak Ridge, North Carolina Well Number Top of Casing Elevation Top of Screen Elevation Bottom of Screen Elevation Depth to Water Groundwater Elevation MW-2 97.27 82.27 57.27 19.39 77.88 MW-3 98.52 85.52 60.52 N/A N/A MW-4 99.13 88.13 63.13 N/A N/A MW-5 98.45 90.45 60.45 N/A N/A MW-6 100.00 92.00 62.00 N/A N/A MW-7 98.85 86.85 63.85 21.28 77.57 MW-8 100.18 84.18 64.18 N/A N/A MW-9 97.17 87.17 62.17 N/A N/A MW-10 98.57 88.57 68.57 21.51 77.06 RW-1 99.12 79.12 54.12 21.11 78.01 VEW-1 99.49 29.49 19.49 N/A N/A Note: Monitor well MW-1 abandoned prior to soil excavation activities and RW-1 was installed to replace the source monitor well. Note: All measurements taken in feet and based on an arbitrary benchmark of 100.00 feet at MW-7; groundwater levels measured on October 15, 2020. Note: All wells labeled as N/A have been destroyed by NCDOT during the Highway 68 widening project X20-818B APPENDIX A HISTORICAL SAMPLING RESULTS Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent 2L Standard Date 8/11/08 10/4/11 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 12/21/15 7/1/16 12/12/16 6/22/17 3/15/18 10/15/20 EPA Method 6200B (ug/L) Benzene 6,070 14,200 5,040 2,140 802 386 343 1,600 922 153 345 923 1,290 1 Toluene 19,400 36,100 14,500 8,960 2,900 1,270 1,700 11,000 7,870 939 1,820 12,000 4,220 600 Ethylbenzene 2,950 4,770 2,540 1,110 659 38 271 1,200 1,020 219 449 869 731 600 Xylenes (total)14,110 23,860 11,670 6,400 3,110 1,547 1,485 6,700 4,970 1,156 2,456 4,850 5,620 500 BTEX (total)42,530 78,930 33,750 18,610 7,471 3,241 3,799 20,500 14,782 2,467 5,070 18,642 11,861 NSE Acetone BDL 3,730 2,440 1,160 176 BDL BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL 2,110 948 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4,000 n-Butylbenzene 146 BDL BDL BDL BDL BDL BDL BDL 60.5 BDL BDL BDL BDL 70 Chloroform BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 4-Chlorotoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL 481 BDL BDL 34 BDL BDL BDL BDL BDL 6.97 BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene 159 276 130 73 43.3 198 17 56 72.6 10.6 25 43.2 76 70 p-Isopropyltoluene BDL BDL BDL BDL BDL BDL BDL BDL 10.2 BDL BDL BDL BDL 25 Methylene Chloride 458 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL 206 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene 892 805 608 309 164 78.1 58.5 260 334 43.4 151 241 300 6 n-Propylbenzene 387 650 373 190 BDL BDL 65.2 160 199 39.3 60.8 117 157 70 1,2,4-Trimethylbenzene 2,670 4,610 2,610 1,240 731 543 372 1,100 1,390 68.6 570 962 1,310 400 1,3,5-Trimethylbenzene 657 1,330 726 325 209 201 127 300 415 BDL 178 246 440 400 IPE 139 794 233 76 20.2 BDL 8 BDL 16.6 BDL 5.69 11.9 BDL 70 MTBE 1,190 5,440 2,490 765 148 32 63.9 170 143 17.3 398 84.5 554 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA MW-1 RW-1 Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent 2L Standard Date 9/30/08 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 12/21/15 7/1/16 12/12/16 6/22/17 3/15/18 10/15/20 EPA Method 6200B (ug/L) Benzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 1 Toluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 1.95 BDL 600 Ethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 1.68 BDL 600 Xylenes (total)BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 9.89 BDL 500 BTEX (total)BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 13.52 BDL NSE Acetone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL BDL BDL BDL BDL BDL BDL 3.2 BDL BDL BDL BDL BDL 4,000 n-Butylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 Chloroform BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 4-Chlorotoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 p-Isopropyltoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 25 Methylene Chloride BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 n-Propylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 1,2,4-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 2.49 BDL 400 1,3,5-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 IPE BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 MTBE BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA MW-2 Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent 2L Standard Date 9/30/08 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 9/30/08 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 EPA Method 6200B (ug/L) Benzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 1 Toluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 600 Ethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 600 Xylenes (total)BDL BDL BDL BDL BDL BDL BDL 4.79 BDL BDL BDL BDL BDL BDL 500 BTEX (total)BDL BDL BDL BDL BDL BDL BDL 4.79 BDL BDL BDL BDL BDL BDL NSE Acetone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4,000 n-Butylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 Chloroform BDL BDL BDL BDL BDL BDL BDL 12.1 27.1 BDL 7.57 4.49 17.4 17.3 70 4-Chlorotoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane BDL BDL BDL BDL BDL BDL BDL 1.23 1.2 BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 p-Isopropyltoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 25 Methylene Chloride BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 n-Propylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 1,2,4-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 1,3,5-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL 2.21 BDL BDL BDL BDL BDL BDL 400 IPE BDL BDL BDL BDL BDL BDL BDL BDL 9.83 5.12 5.36 5.46 10.8 6.56 70 MTBE BDL BDL BDL BDL BDL BDL BDL 226 644 110 98.1 63.6 517 197 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA MW-3 MW-4 Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent 2L Standard Date 3/11/09 10/4/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 12/21/15 7/1/16 EPA Method 6200B (ug/L) Benzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 1 Toluene BDL BDL BDL BDL BDL BDL BDL BDL BDL 600 Ethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 600 Xylenes (total)BDL BDL BDL BDL BDL BDL BDL BDL BDL 500 BTEX (total)BDL BDL BDL BDL BDL BDL BDL BDL BDL NSE Acetone BDL BDL BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL BDL BDL BDL BDL BDL BDL BDL BDL 4,000 n-Butylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 Chloroform BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 4-Chlorotoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL BDL BDL BDL BDL BDL BDL BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 p-Isopropyltoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL 25 Methylene Chloride BDL BDL BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL BDL BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 n-Propylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 1,2,4-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 1,3,5-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 IPE BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 MTBE BDL BDL BDL BDL BDL BDL BDL BDL BDL 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA MW-5 Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent 2L Standard Date 3/11/09 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 EPA Method 6200B (ug/L) Benzene BDL BDL BDL BDL BDL BDL BDL 1 Toluene BDL BDL BDL BDL BDL BDL BDL 600 Ethylbenzene BDL BDL BDL BDL BDL BDL BDL 600 Xylenes (total)BDL BDL BDL BDL BDL BDL BDL 500 BTEX (total)BDL BDL BDL BDL BDL BDL BDL NSE Acetone BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL BDL BDL BDL BDL BDL BDL 4,000 n-Butylbenzene BDL BDL BDL BDL BDL BDL BDL 70 Chloroform 3.55 22.2 34.8 22.9 12.4 BDL 14.7 70 4-Chlorotoluene BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL BDL BDL BDL BDL BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane BDL BDL BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene BDL BDL BDL BDL BDL BDL BDL 70 p-Isopropyltoluene BDL BDL BDL BDL BDL BDL BDL 25 Methylene Chloride BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene BDL BDL BDL BDL BDL BDL BDL 6 n-Propylbenzene BDL BDL BDL BDL BDL BDL BDL 70 1,2,4-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL 400 1,3,5-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL 400 IPE BDL BDL BDL BDL BDL BDL BDL 70 MTBE 2.33 2.33 4.69 1.76 1.45 BDL 2.35 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA MW-6 Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent 2L Standard Date 3/11/09 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 12/21/15 7/1/16 12/12/16 6/22/17 3/15/18 10/15/20 5/8/09 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 EPA Method 6200B (ug/L) Benzene 33.7 14.8 11.3 BDL BDL BDL BDL 2.3 BDL 1.33 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 1 Toluene 10.1 BDL BDL BDL BDL BDL BDL BDL BDL 0.62 BDL 0.75 BDL BDL BDL BDL BDL BDL BDL BDL 600 Ethylbenzene 19.9 2.2 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 600 Xylenes (total)378 75.7 33.3 15.7 BDL BDL BDL 7.9 BDL 2.1 12.7 BDL BDL BDL BDL BDL BDL BDL BDL BDL 500 BTEX (total)441.7 92.7 44.6 15.7 BDL BDL BDL 10.2 BDL 4.05 12.7 0.75 BDL BDL BDL BDL BDL BDL BDL BDL NSE Acetone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane 1.34 2.87 BDL BDL 1.02 1.79 BDL 5.8 4.15 5.08 5.31 1.85 BDL BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL 0.85 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4,000 n-Butylbenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 Chloroform 36.4 68.4 83.3 66.3 20.9 30.5 8.8 95 75.1 101 62.9 41.6 2.52 4.22 BDL BDL BDL 0.83 BDL BDL 70 4-Chlorotoluene 9.16 5.39 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL 0.5 BDL BDL BDL BDL BDL 1.6 0.9 3.69 2.5 BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL 0.53 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane 3.91 4.37 BDL BDL BDL BDL BDL 1.4 BDL 1.28 2.01 1.03 BDL BDL BDL BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL 1 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene 4.45 1.3 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 p-Isopropyltoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 25 Methylene Chloride BDL BDL BDL BDL BDL BDL BDL 2.5 1.92 3.33 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene BDL 1.28 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 n-Propylbenzene 5.62 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 1,2,4-Trimethylbenzene 81.7 21.1 7.9 9.9 BDL BDL BDL 1.6 BDL 0.62 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 1,3,5-Trimethylbenzene 3.95 1.12 16.9 BDL BDL BDL BDL BDL BDL 2.02 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 IPE 5.18 5.05 5.2 BDL BDL 2.19 0.68 5.3 1.76 4.17 6.5 3.62 BDL BDL BDL BDL BDL BDL BDL BDL 70 MTBE 5,510 3,590 3,160 1,690 138 297 55.5 780 317 1,060 1,710 2,730 35.9 BDL BDL BDL BDL BDL BDL BDL 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA MW-7 MW-8 Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent 2L Standard Date 5/8/09 9/14/10 5/3/12 7/19/13 11/21/13 6/3/14 7/21/09 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 12/21/15 7/1/16 12/12/16 6/22/17 3/15/18 10/15/20 EPA Method 6200B (ug/L) Benzene 2,610 576 1,730 653 133 503 3.83 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 1 Toluene 3,800 182 1,950 63.6 29.5 2.67 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.69 BDL 600 Ethylbenzene 812 54.6 409 24.9 8.85 8.69 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 600 Xylenes (total)4,760 334 3,107 350 136.7 233.4 20.12 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 500 BTEX (total)11,982 1,146 7,196 1091.5 308.05 747.76 23.95 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.69 BDL NSE Acetone BDL 61.8 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL 42.5 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 4,000 n-Butylbenzene BDL 1.75 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 Chloroform BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 4-Chlorotoluene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL 16 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene BDL 8.77 BDL BDL 15.6 6.59 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 p-Isopropyltoluene BDL BDL BDL BDL BDL 2.95 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 25 Methylene Chloride BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL 8.8 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene 692 29.6 161 6 8.39 21.1 BDL 1.4 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 6 n-Propylbenzene BDL 6.99 61 BDL 1.2 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 1,2,4-Trimethylbenzene 754 119 581 131 56.8 98.7 4.22 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 1,3,5-Trimethylbenzene 193 37 160 36.3 15.6 25.7 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 400 IPE BDL 33.7 82 24.5 10.5 23.9 BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL BDL 70 MTBE 1,060 189 760 171 57.8 157 239 0.76 BDL BDL BDL BDL BDL 0.83 BDL 2.58 2.97 0.71 BDL 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA MW-9 MW-10 Historical Sampling Results Northwest Superette Oak Ridge, North Carolina Constituent SW-1 2L Standard Date 3/11/09 9/14/10 12/1/11 5/3/12 7/19/13 11/21/13 6/3/14 9/14/10 EPA Method 6200B (ug/L) Benzene BDL BDL BDL BDL BDL BDL BDL BDL 1 Toluene BDL BDL BDL BDL BDL BDL BDL BDL 600 Ethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL 600 Xylenes (total)BDL BDL BDL BDL BDL BDL BDL BDL 500 BTEX (total)BDL BDL BDL BDL BDL BDL BDL BDL NSE Acetone BDL BDL BDL BDL BDL BDL BDL BDL 6,000 Bromodichloromethane BDL BDL BDL BDL BDL BDL BDL BDL 0.6 Bromoform BDL BDL BDL BDL BDL BDL BDL BDL 4 2-Butanone BDL BDL BDL BDL BDL BDL BDL BDL 4,000 n-Butylbenzene BDL BDL BDL BDL BDL BDL BDL BDL 70 Chloroform BDL BDL BDL BDL BDL BDL BDL BDL 70 4-Chlorotoluene BDL BDL BDL BDL BDL BDL BDL BDL 24 Dibromochloromethane BDL BDL BDL BDL BDL BDL BDL BDL 0.4 2-Hexanone BDL BDL BDL BDL BDL BDL BDL BDL 40 1,2-Dichloroethane BDL BDL BDL BDL BDL BDL BDL BDL 0.4 1,2-Dichloropropane BDL BDL BDL BDL BDL BDL BDL BDL 0.6 1,4-Dichlorobenzene BDL BDL BDL BDL BDL BDL BDL BDL 6 Isopropylbenzene BDL BDL BDL BDL BDL BDL BDL BDL 70 p-Isopropyltoluene BDL BDL BDL BDL BDL BDL BDL BDL 25 Methylene Chloride BDL BDL BDL BDL BDL BDL BDL BDL 5 Methyl Isobutyl Ketone BDL BDL BDL BDL BDL BDL BDL BDL 100 Naphthalene BDL BDL BDL BDL BDL BDL BDL BDL 6 n-Propylbenzene BDL BDL BDL BDL BDL BDL BDL BDL 70 1,2,4-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL 400 1,3,5-Trimethylbenzene BDL BDL BDL BDL BDL BDL BDL BDL 400 IPE BDL BDL BDL BDL BDL BDL BDL BDL 70 MTBE BDL BDL BDL BDL BDL BDL BDL BDL 20 BDL = Below Detection Limits NSE = No Standard Established X20-818TBA VEW-1 APPENDIX B CONTAMINANT CONCENTRATIONS VS. TIME GRAPHS 0 2,000 4,000 6,000 8,000 10,000 12,000 14,000 16,000 Benzene Concentration (ug/L)Time Northwest Superette Benzene Concentration vs. Time RW-1 MW-7 MW-9 0 100 200 300 400 500 600 700 800 900 1000 Naphthalene Concentration (ug/L)Time Northwest Superette Napthalene Concentration vs. Time RW-1 MW-9 0 1000 2000 3000 4000 5000 6000 MTBE Concentration (ug/L)Time Northwest Superette MTBE Concentration vs. Time RW-1 MW-4 MW-7 MW-9 APPENDIX C COMPILATION OF COSTS / CHRONOLOGY OF REMEDIATION ACTIVITIES Compilation of Costs / Chronology of Remediation Activities Northwest Superette Oak Ridge, NC Date(s)Activity Cost 5/6/08 - 10/7/08 Initial Abatement Action Report and Limited Site Assessment $64,734.11 3/5/09 - 8/18/09 Comprehensive Site Assessment $33,498.00 9/14/10 - 1/18/11 Pre-CAP Monitoring Report $4,806.00 1/19/11 - 3/25/11 Corrective Action Plan $4,896.00 9/12/11 - 10/5/11 Soil Excavation $80,979.89 12/1/11 - 12/28/11 MW Sampling, Active Remediation Monitoring Report $8,547.00 4/23/12 - 5/18/12 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $11,833.50 2/4/13 - 3/6/13 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $12,836.00 11/11/13 - 1/2/14 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $13,012.75 5/5/14 - 7/8/14 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $13,249.25 11/30/15 - 1/18/16 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $12,155.75 6/13/16 - 8/19/16 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $11,593.75 11/28/16 - 12/23/16 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $10,164.25 6/5/17 - 8/18/17 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $12,644.75 2/26/18 - 5/21/18 week-long MMPE, MW Sampling, Active Remediation Monitoring Report $12,111.00 Total:$307,062.00 APPENDIX D PROPOSED REMEDIATION SCHEDULE FROM CORRECTIVE ACTION PLAN Proposed Remediation Schedule from Corrective Action Plan Northwest Superette Oak Ridge, NC The target startup and completion dates are summarized as follows: Item Completion Date Pre-approval form submittal Within 60 days of for soil excavation and disposal CAP approval Soil excavation activities 90 days after approval of pre-approval request Soil Cleanup Report Within 60 days after soil excavation Pre-approval form submittal Within 60 days of for recovery well installation CAP approval and initial MMPE event Drilling activities 90 days after approval of pre-approval request MMPE remediation event Within 90 days after well installation Active Remediation Monitoring Semi-annually until (following MMPE event) site is closed Remediation Goals Achieved Estimated 3 to 5 years M20-818 Schedule APPENDIX E LABORATORY ANALYTICAL RESULTS