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Home My WebLink AboutDERR-2024-006825Facility Information Facility Name:FORMER GAS STATION AT SOUTH WASHINGTON PLAZA Release ID:OFV Facility Address:3965 S WASHINGTON BLVD SOUTH OGDEN, UT 84403 Facility ID:1200678 Notification Date:10/24/2022 Owner Name:SOUTH WASHINGTON PLAZA & ASSOCIATES LC Reporting Party:Craig Gasser Owner Address:3441 100 E BOUNTIFUL, UT 84010 Project Manager:Mark Crim Site Assessment Information a. Contaminant Source Information Cause of Release (if known) Product Released Amount Released (gal) Size (gal) # of USTs Tank Piping Disp Over/Spill Other Comments Gasoline UNK 10 K Yes Diesel UNK 10 K Yes Waste Oil Unknown Other Tank Piping Disp Free Prod Cont Soil Sources Removed:Yes Yes Yes No No b. Land Use Information Current Land use at the Site:Commercial Surrounding Neighborhood:Commercial (Note: Surrounding land use is Residential if one or more residences share a common property line with the Facility) c. Soil Information Soil Type(s) Depth to Contaminated Soil (feet below land surface): 10-15 SM-Silty sands Method of Soil Type Identification:Unified Soil Classification d. Groundwater Information Was groundwater encountered?:Yes Thickness of Free Product:NA Depth to groundwater (feet below land surface): 14 Is groundwater impacted at any concentration: Yes Groundwater flow direction:S SW Measured Slope direction of surface topography:S e. Distance from Highest Measured Contaminated Concentrations and Sampling Location to Nearest Potential Receptor Receptors:(Enter distance to each receptor from corresponding sampling location in feet) Distance- Location Distance- Location Water Line:35 - MW-8 Sewer Line:40 - MW-8 Building Desc:Commercial Electrical:10 - MW-3 Natural Gas:30 - MW-8 Other Desc: Building:>30 - MW-5 Telephone:>30 - MW-8 Property Line >30 - MW-5 Storm Drain:15 - MW-8 Other(specify): - Receptors Within 500 feet: Municipal Well:>500 Domestic Well:>500 Irrigation Well:>500 Other: Surface Water(specify type: lake, stream, creek, river, wetland):Dist: >500 Desc: Weber River Utah's RBCA Tier 1 Worksheet Printed on: 2/27/2024 2:58:26 PM Facility History - Executive Summary Site history beginning in about 1973, includes the operation of several USTs, with removal of the UST system in about 1983. The discovery of petroleum impacted soil and groundwater in 2022 led to further investigations at the site from 2023 to 2024. No work has been done to clean-up the petroleum contamination discovered at the site, and soil and groundwater contamination that remains exceeds the ISL standard in several areas, including near a southern utility corridor. See supplemental discussion. RBCA Tier 1 Screening Level Evaluation Groundwater(mg/L)Soil(mg/Kg) Constituent ISL/Tier 1 Level Highest Concentration and Sampling Location ISL/Tier 1 Level Highest Concentration and Sampling Location Benzene 0.005/0.30 <0.005 MW-5 0.20/0.90 <0.12 MW-5 Toluene 1.0/3.00 <0.012 MW-5 9.0/25.0 <0.30 MW-5 Ethylbenzene 0.7/4.00 1.02 MW-5 5.0/23.0 2.16 MW-5 Xylenes 10.0/10.0 3.92 MW-5 142.0/142.0 25.1 MW-5 Napthalene 0.70/0.70 0.884 MW-5 51.0/51.0 7.35 MW-5 MTBE 0.20/0.20 <0.005 MW-5 0.30/0.30 <0.12 MW-5 TPH-gasoline 1.0/10.0 12.8 MW-5 150/1500 397 MW-5 TPH-diesel 1.0/10.0 9.2 MW-5 500/5000 316 MW-5 Oil and Grease/TRPH 10.0/10.0 NT NT 1000/10000 NT NT Recommended Tier 1 Actions All contaminant concentration levels are below ISLs or below Tier 1 screening levels and no receptors are within the critical distances. Recommendation - No further action. Tier 1 criteria (contaminant concentration and/or distance to receptors) are exceeded at the site. Recommendation - See attached supplemental information worksheet. Evaluation Completed by:Date: DERR Project Manager's Signature Utah's RBCA Tier 1 Worksheet Printed on: 2/27/2024 2:58:26 PM 2-28-2024 SUPPLEMENTAL INFORMATION FOR NO FURTHER ACTION South Washington Plaza and Associates Property 3965 South Washington Boulevard, South Ogden, Utah Facility Identification No. 1200678, Release OFV Facility History and Contaminant Source Elimination and Control In October 2022, a realty-styled subsurface investigation revealed soil and groundwater contamination attributed to a former Chevron service station that had its underground storage tanks (USTs) closed in 1983. Diesel and gasoline impacts exceeded the Division of Environmental Response and Remediation (DERR) Initial Screening Level (ISL) standard for soil and groundwater, and more work was needed to define the extent of the contamination. On October 25, 2022, Release ID ‘OFV’ was assigned to the South Washington Plaza and Associates Property (SWP) site. Site history indicates that petroleum operations on the property existed from about 1973 to 1981, as a Chevron service station with at least two USTs. The USTs were reportedly removed in 1983. In August 2022, a Phase I Environmental Site Assessment (ESA) was performed for the landowners, which led to Phase II ESA with soil and groundwater samples collected and analyzed (see Figure: 1-Site Location Map and Figure: 2-Aerial Map). In September 2022, a Phase II ESA occurred that focused on environmental sampling in and about the former UST system. The sampling technician was not certified as a DERR-approved environmental sampler. Seven soil borings (B-1 through B-7) had soil and groundwater samples collected for analysis. Results of the soil sampling showed impacts above the ISL standard for total petroleum hydrocarbons diesel range organics (TPH-DRO) only, at B-3, 11’ below grade (bg). Groundwater, collected at about 12’ bg, showed that B-1 and B-5 exceeded the ISL standard for total petroleum hydrocarbons gasoline range organics (TPH-GRO) and that B-5 also had TPH-DRO exceeding the ISL standard (see Figure: 3 Soil Boring Map and Table: 4 Soil and Table: 7 Groundwater). In February 2023, Rockwell Solutions Inc. (Rockwell) performed a site investigation that began with re-drilling former borings B-1, B-3 and B-5, sampled by an uncertified sampler, and also placed six additional borings. All of the soil borings, except B-3d, had groundwater monitoring wells (MW) installed. MW-1 through MW-8 were placed in an effort to describe the groundwater plume and soil -source areas. Results of soil sampling indicated that MW-5 only, exceeded the ISL standard for TPH-GRO. The initial groundwater sampling from the MWs showed that MW-5 and MW-8 exceeded the ISL standard for TPH-DRO and TPH-GRO, while MW-7 exceeded the ISL standard for TPH-GRO (see Figure: 4 Soil Boring and MW Map and Table: 1 Soil, Table: 2 GW). From February 2023 through January 2024, four groundwater monitoring events occurred and results show that at MW-5, there are ongoing exceedances of the ISL standard for TPH-DRO and TPH-GRO. At the southern property boundary, Chimes View Drive, the head of the groundwater plume at MW-8 periodically exceeds the ISL standard for TPH-DRO (see Figure: 4 and Table: 1B). Thus, site history beginning in about 1973, includes the operation of several USTs, with removal of the UST system in about 1983. The discovery of petroleum impacted soil and groundwater in 2022 led to further investigations at the site from 2023 to 2024. No work has been done to clean-up the petroleum contamination discovered at the site, and soil and groundwater contamination that remains exceeds the ISL standard in several areas, including near a southern utility corridor. Because remaining petroleum affected soil and groundwater exceeds the ISL standard and the distance criteria to several receptors, Release ‘OFV’ needs further review. The following discussion of the impacts of remaining contamination to public health and the environment is presented, with a recommendation for No Further Action (NFA), coupled with an in-place contamination map and notification to the Blue Stakes of Utah network. Current Land Use Current land use at the site is that of a commercial strip mall with asphalt covered parking above the area of petroleum impacts. Nature and Extent of Contamination The nature of the contamination is diesel and gasoline associated with a leaking UST system that was closed in 1983. The highest level of remaining soil contamination is found at sampling location MW-5, existing from about 10 feet to 15 feet bg. The footprint of the groundwater plume, is about 7,200 square feet, with an axis from MW- 7 to MW-8, and an east to west component between MW-3 to MW-6. The groundwater plume at 14’ bg, is about 120 feet long and about 60 feet wide; it has a gradient of 0.03 ft/ft and trends southwest. The highest groundwater impacts at the site are found at MW-5, with the groundwater plume terminating near MW-8 at Chimes View Drive (see Figure: 5 Remaining Contamination Above the ISL Standard and Utility Map). Impact of Remaining Contamination on Public Health and the Environment Several exposure pathways to the remaining contamination do exist, and can be controlled to reduce exposure risks. The greatest risk to exposure, would be the construction worker, who could encounter petroleum contamination if soils or groundwater are disturbed. Soil-Leaching-to-Groundwater and Groundwater Ingestion Exposure Pathway Soil based contamination has leached to groundwater, but the remaining contamination should not contribute to an increase in the mass of the groundwater plume. Soils with TPH-GRO contamination remaining above the ISL standard are found at MW-5, near a former dispenser that was in front of the former service station. The groundwater plume above the ISL standard is beneath the strip mall parking lot, at a depth of about 14’ bg, described by MW-7 to MW-8 and MW-3 to MW-6. Various utilities such as a storm drains, waterlines and deeper sewer conduits exist along the south boundary of the site, with on-site utilities entering the property on its western boundary, greater than 100’ from the source area. The construction worker is most likely to encounter petroleum- impacted groundwater if it is disturbed from 14’ bg. A 500’ radius search for points of diversion was performed using the Utah Division of Water Rights (DWR) database. No water right or point of diversion exists within 500’ of the site (see Attachment ‘A’ for DWR Radius Search). Site-Specific Cleanup Levels (SSCLs) and Groundwater Ingestion SSCLs were determined for the highest remaining soil and groundwater contamination at the site found at MW- 5 and for MW-8, near a utility corridor. Input values include, a commercial setting, groundwater from 14’ to 17’ bg, the presence of silty sand, and the area of concern covered with asphalt. Regarding analytic data, MBTEXN, TPH-GRO values (C5-C10 range constituents) and TPH-DRO values (C11-C16 range constituents) were utilized. At MW-5, SSCL calculations show that soil failed the ‘Subsurface Soil to Indoor Air’ and the ‘Subsurface Soil to Outdoor Air’ pathways for benzene, xylenes, naphthalene and several aliphatic groups. Of note is that the input value for benzene is below the ISL standard and the laboratory detection level used was, 0.12 mg/kg. At MW-5, SSCL calculations show that groundwater failed the ‘Groundwater Ingestion’ pathway for several alkyl groups, PAH and numerous aliphatics. At MW-8, SSCL calculations show that soil failed the ‘Subsurface Soil to Indoor Air’ pathway for benzene, and an aliphatic chemical, undecane. Of note is that the input value for benzene is below the ISL standard and the laboratory detection level used was, 0.01 mg/kg. At MW-8, SSCL calculations show that groundwater failed the ‘Groundwater Ingestion’ pathway for several alkyl groups, PAH and numerous aliphatics. Regarding the ‘Groundwater Ingestion’ pathway, there is no use of the groundwater at the site. Only the construction worker scenario should be considered for potential groundwater ingestion. A discussion of the other completed exposure pathways, is presented below (see Attachment B-1and B-2 for SSCL calculations). Vapor-Intrusion-to-Indoor Air Exposure Pathway Vapor intrusion to indoor air is possible according to the SSCL calculus at MW-5 and MW-8. However, the onsite building, a strip mall, is more than 80’ lateral north to MW-5, and a third party building to the east is more than 160’ lateral to MW-5. At MW-5 and MW-8, vapor intrusion to indoor air is possible as a confined space issue, potentially affecting construction workers. Risks to construction workers can be mitigated by placing the surrounding utility corridor on the Blue Stakes of Utah network and utilizing an in-place remaining contamination map with a NFA letter. Vapor-Intrusion-to-Outdoor Air Exposure Pathway Vapor intrusion to outdoor air is possible according to the SSCL calculus at MW-5. At MW-5, a parking lot currently exists over the area and consists of an asphalt cover. Outdoor air exposure scenarios would include construction workers, if impacted soils are disturbed below 12’ bg. Risks to construction workers can be mitigated, by placing the surrounding utility corridor on the Blue Stakes of Utah network and utilizing an in-place remaining contamination map with a NFA letter. Surface Soil Exposure Pathway: Dermal Contact, Particulate Inhalation and Ingestion, and Construction Worker Dermal contact, particulate inhalation and ingestion did not exceed the SSCL calculations for MW-5 or MW-8, and are only possible via the construction worker scenario at the site, and the utility corridor at Chimes View Drive. Other: Exposure Pathways-Utility Lines Soil and groundwater contamination potentially affecting utility lines or workers is found within the contaminant plume, which exists from MW-7 to MW-8 and MW-3 to MW-6. The contaminant plume is from 12’ to 16’ bg and poses no imminent threat to human health or the environment. Sensitive utilities, such as drinking water and sanitary sewer layouts, exist south of the site at Chimes View Drive. Utilities that support the strip mall building are sanitary sewer, drinking water and natural gas lines that enter the complex west of the area of concern by more than 150’ lateral. Several shallow utilities such as subgrade electric, telephone and storm sewer exist over the plume near MW-5 and MW-8. Only under the construction worker scenario could the remaining petroleum- impacted media be encountered, below 12’ bg. Risks to construction workers can be mitigated by placing the surrounding utility corridor on the Blue Stakes of Utah network and utilizing an in-place remaining contamination map with a NFA letter (see Figure: 5 Remaining Contamination Above the ISL Standard and Utility Map) Economic Considerations and Cost-Effectiveness of Cleanup Options Considering the economics of cleanup for this release is one of cost versus threat. In this case, the potential costs of treating soil by removal, and groundwater treatment or monitoring to attenuation, could exceed tens of thousands of dollars. The risks of exposure to the soil and groundwater primarily concern the construction worker for groundwater ingestion or confined space vapor threats. There is a low risk to leaving the contamination in- place. Requiring additional work is unnecessary. Precautions for exposure to impacted soil or groundwater can be managed by Blue Stakes awareness near the utility corridor and placing on record an in-place remaining contamination map. Technology Available for Cleanup The technology does exist for the cleanup of the SWP release site. Removal of soil contamination is the best option for treatment at the site, and groundwater could be treated or monitored to attenuation. But the lack of any on-going threat to public health or the environment, excepting the construction worker, suggests this release of petroleum be closed of concern. Recommendation for No Further Action It is recommended that the petroleum contamination associated with the SWP release site be closed of concern and that NFA status be granted to DERR Release OFV. The leaking UST system was closed in 1983, and soil contamination exists in situ, with an associated groundwater plume. The release has been evaluated, including threats of remaining contamination to public health and the environment. A review of soil and groundwater data, and of sensitive receptors in the area suggests that only under the construction worker scenario, is petroleum contaminated soil or groundwater to be encountered at the site. A NFA letter, coupled with a notice to the Blue Stakes of Utah network and an in-place remaining contamination map, should be issued to the SWP site. FIGURES 2/20/24, 3:42 PM Map https://maps.waterrights.utah.gov/EsriMap/map.asp 1/1 Figure 1: Site Location Map for Site OFV 0 0.1 0.2mi N S W E 2/21/24, 1:01 PM Map https://maps.waterrights.utah.gov/EsriMap/map.asp 1/1 Figure 2: Aerial Map for Site OFV 0 100 200ft N S W E Figure 3: Soil Boring Map from ESA II-2022 (from CMT Technical Services) Figure 4: Soil Boring and Groundwater Monitoring Well Map (from Rockwell’s Figure 1, Site Map 2-2023) Figure 5: Remaining Contamination Above the ISL Standard and Utility Map (from Rockwell’s Figure 1, Site Map 2-2023) Legend: Storm and Sanitary Sewer Water Natural Gas GW Plume Soil > ISL Tables Table 4 Soil and Table 7 Groundwater Analytic Results from ESA II-2022 (from CMT Technical Services) Table 1 Soil and Table 2 Initial Groundwater Analytic Results (from Rockwell 2-2023) Table 1B Complete Groundwater Analytic Results (from Rockwell’s Table 1, Groundwater Monitoring Report, 1-2024) ATTACHMENTS 2/20/24, 3:37 PM Map https://maps.waterrights.utah.gov/EsriMap/map.asp 1/1 Attachment A: Water Rights Map for Site OFV 5 0 150 300ft N S W E ATTACHMENT B1 SSCL at MW-5 Page 1 of 3SSCL Calculator Prepared for:SSCL Calculator Prepared by: Site name: Site address: Facility ID: Release ID: Contact name: Contact phone: Contact e-mail: Site-Specific Cleanup Levels* for Commercial/ Industrial Receptors Air Groundwater Soil SSCLair SSCLwing SSCLwesp SSCLwamb SSCLs-leach SSCLsesp SSCLsamb SSCLss (See Eq. D.1)(See Eq. D.2)(See Eq. D.3)(See Eq. D.4)(See Eq. D.5)(See Eq. D.6)(See Eq. D.7)(See Eq. D.8) Air Groundwater Groundwater Groundwater Subsurface soil Subsurface soil Subsurface soil Surface Soil Inhalation Ingestion Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Leaching to groundwater (groundwater ingestion) Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Ingestion of soil, inhalation of vapors and particles, and dermal contact µg/m3 air µg/m3 air mg/L water mg/L water mg/L water mg/L water mg/kg soil mg/kg soil mg/kg soil mg/kg soil mg/kg soil Benzene (71-43-2)c 4.93E-01 0.297 SG-1 7/28/2011 (slab atten. factor *0.03)9.87E-03 7.22E-01 1.25E+02 0.005 MW-5 2.57E-01 3.74E-03 1.31E-01 5.33E+00 0.12 MW-5@12' Toluene (108-88-3)nc 7.31E+03 1.291 SG-1 7/28/2011 (slab atten. factor *0.03)8.18E+00 1.21E+04 2.10E+06 0.012 MW-5 3.42E+02 7.51E+01 2.63E+03 5.38E+03 0.3 MW-5@12' Ethylbenzene (100-41-4)nc 1.48E+03 0.150 SG-1 7/28/2011 (slab atten. factor *0.03)1.02E+01 2.68E+03 4.70E+05 1.02 MW-5 7.44E+02 2.32E+01 8.10E+02 6.31E+03 2.16 MW-5@12' Xylenes (1330-20-7)nc 1.48E+02 0.571 SG-1 7/28/2011 (slab atten. factor *0.03)2.04E+01 2.38E+02 4.13E+04 3.92 MW-5 1.51E+03 3.19E+00 1.11E+02 5.22E+03 25.1 MW-5@12' Naphthalene (91-20-3)nc 4.39E+00 0.300 SG-1 7/28/2011 (slab atten. factor *0.03)2.04E+00 1.27E+01 1.60E+03 0.884 MW-5 1.83E+02 2.21E+00 7.74E+01 2.45E+02 7.35 MW-5@12' MTBE (1634-04-04)nc 4.38E+03 0.150 SG-1 7/28/2011 (slab atten. factor *0.03)5.11E-01 3.10E+03 2.01E+05 0.005 MW-5 6.56E+00 1.70E+02 5.95E+03 3.40E+02 0.12 MW-5@12' Alkyl benzenes (C9-C10) [average values]nc 3.07E+02 4.09E+00 5.77E+02 1.01E+05 12.8 MW-5 5.80E+02 9.96E+00 3.48E+02 2.36E+03 9 MW-5@12' Alkyl naphthalenes (C11-C13) [average values]nc 3.07E+02 4.09E+00 8.49E+02 1.09E+05 9.2 MW-5 2.72E+03 1.07E+03 3.73E+04 9.53E+03 316 MW-5@12' Total PAHs (C12-C22) [average values]nc 1.53E+02 3.07E+00 1.40E+02 2.32E+04 9.2 MW-5 1.80E+04 3.89E+02 1.36E+04 5.62E+03 316 MW-5@12' Aliphatics (C5-C6) [Hexane (110-54-3)]nc 3.07E+02 0.270 SG-1 7/28/2011 6.13E+00 5.08E+02 9.05E+04 12.8 MW-5 8.93E+03 7.32E-01 2.56E+01 3.31E+03 397 MW-5@12' Aliphatics (C7-C8) [Heptane (142-82-5)]nc 3.07E+02 0.282 SG-2 1/10/2013 (slab atten. factor *0.03)6.13E+00 6.14E+02 1.10E+05 12.8 MW-5 1.78E+04 9.98E-01 3.49E+01 3.31E+03 397 MW-5@12' Aliphatics (C9-C10) [Nonane (111-84-2)]nc 1.48E+03 0.390 SG-2 1/10/2013 (slab atten. factor *0.03)1.02E+01 3.47E+03 6.18E+05 12.8 MW-5 8.54E+04 6.93E+00 2.42E+02 6.31E+03 397 MW-5@12' Aliphatics (C11-C12) [Undecane (1120-21-4)]nc 1.48E+03 1.02E+01 3.94E+03 7.03E+05 9.2 MW-5 3.55E+05 4.03E+01 1.41E+03 6.31E+03 316 MW-5@12' Aliphatics (C13-C16) [Hexadecane (544-76-3)]nc 1.48E+03 1.02E+01 4.55E+03 8.11E+05 9.2 MW-5 4.79E+06 6.34E+02 2.22E+04 6.31E+03 316 MW-5@12' Aliphatics (C17-C21) [Heptadecane (629-78-7)]nc 1.02E+04 2.04E+02 3.75E+04 6.69E+06 9.2 MW-5 7.58E+09 6.06E+05 2.12E+07 1.26E+05 316 MW-5@12' Aliphatics (C22-C35) [Heptadecane (629-78-7)]nc 1.02E+04 2.04E+02 3.75E+04 6.69E+06 9.2 MW-5 7.58E+09 6.06E+05 2.12E+07 1.26E+05 316 MW-5@12' Mark Crim DEQ/ERR Date prepared:1/20/2024 South Washington Plaza 3965 South washington Blvd., South Ogden, Utah 1200678 OFV Soil Comments (e.g. Sample ID, Sample Depth, Sample Date, etc.) Highest Soil Concentrations Remaining at the Site Name: Company, Agency, other: Phone: E-mail: UST Consultant Cert. #: Highest Air Concentrations Remaining at the Site Air Comments (e.g. Sample ID, Sample Date, etc.) Groundwater Comments (e.g. Sample ID, Sample Date, etc.)Chemical Name (CAS #) Pr i m a r y C h e m i c a l s o f C o n c e r n To t a l P e t r o l e u m H y d r o c a r b o n F r a c t i o n s Highest Groundwater Concentrations Remaining at the Site SSCL.OFV.MW-5 Page 1 of 3 2/21/2024 10:35 AM Page 2 of 3Site-Specific Cleanup Levels* for Commercial/ Industrial Receptors Air Groundwater Soil SSCLair SSCLwing SSCLwesp SSCLwamb SSCLs-leach SSCLsesp SSCLsamb SSCLss (See Eq. D.1)(See Eq. D.2)(See Eq. D.3)(See Eq. D.4)(See Eq. D.5)(See Eq. D.6)(See Eq. D.7)(See Eq. D.8) Air Groundwater Groundwater Groundwater Subsurface soil Subsurface soil Subsurface soil Surface Soil Inhalation Ingestion Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Leaching to groundwater (groundwater ingestion) Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Ingestion of soil, inhalation of vapors and particles, and dermal contact µg/m3 air µg/m3 air mg/L water mg/L water mg/L water mg/L water mg/kg soil mg/kg soil mg/kg soil mg/kg soil mg/kg soil Soil Comments (e.g. Sample ID, Sample Depth, Sample Date, etc.) Highest Soil Concentrations Remaining at the Site Highest Air Concentrations Remaining at the Site Air Comments (e.g. Sample ID, Sample Date, etc.) Groundwater Comments (e.g. Sample ID, Sample Date, etc.)Chemical Name (CAS #) Pr i m a r y C h e m i c a l s o f C o n c e r n Highest Groundwater Concentrations Remaining at the Site Acenaphthylene (208-96-8)nc 1.53E+02 3.07E+00 1.38E+03 8.85E+04 8.21E+02 1.59E+03 5.54E+04 6.19E+03 Acenaphthene (83-32-9)nc 8.69E+01 6.13E+00 6.05E+02 4.35E+04 1.42E+03 5.61E+02 1.96E+04 4.28E+03 Fluorene (86-73-7)nc 5.62E+01 4.09E+00 6.21E+02 3.58E+04 1.52E+03 1.05E+03 3.67E+04 4.05E+03 Phenanthrene (85-01-8)nc 1.53E+02 3.07E+00 4.06E+03 1.83E+05 2.35E+03 1.56E+04 5.45E+05 1.05E+04 Anthracene (120-12-7)nc 4.38E+02 3.07E+01 9.78E+03 4.54E+05 2.22E+04 3.51E+04 1.23E+06 5.35E+04 Fluoranthene (206-44-0)nc 5.83E+01 4.09E+00 5.02E+03 1.93E+05 1.06E+04 6.82E+04 2.39E+06 1.39E+04 Pyrene (129-00-0)nc 4.38E+01 3.07E+00 4.68E+03 1.76E+05 7.34E+03 5.93E+04 2.07E+06 1.07E+04 Benz(a)Anthracene (56-55-3)c 1.96E-01 3.92E-04 1.76E+01 6.57E+02 3.71E+00 8.81E+02 3.08E+04 2.00E+00 Chrysene (218-01-09)c 1.96E+00 3.92E-02 4.59E+02 1.67E+04 2.96E+02 1.85E+04 6.48E+05 1.91E+02 Benzo(b)Fluoranthene (205-99-2)c 1.96E-02 3.92E-04 1.15E+00 4.72E+01 3.02E+00 4.58E+01 1.60E+03 1.82E+00 Benzo(k)-Fluoranthene (207-08- 09)c 1.96E-01 3.92E-03 7.64E+02 2.68E+04 4.40E+01 4.62E+04 1.62E+06 1.99E+01 Benzo(a)-Pyrene (50-32-8)c 2.35E-03 3.92E-05 2.49E+00 8.76E+01 4.77E-01 1.63E+02 5.70E+03 1.98E-01 Indeno(1, 2, 3-Cd)Pyrene (193-39- 5)c 2.35E-02 3.92E-04 1.38E+03 9.75E+03 2.95E-01 5.60E+03 3.95E+04 1.97E+00 Dibenzo-(a, h)Anthracene (53-70- 3)c 2.35E-02 3.92E-04 5.74E+01 2.02E+03 2.69E+01 2.13E+04 7.43E+05 2.00E+00 Benzo (g, h, i)-Perylene (191-24-2)nc 1.53E+02 3.07E+00 1.02E+05 3.62E+06 8.85E+04 1.58E+07 5.52E+08 1.55E+04 Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not usedAd d i t i o n a l C h e m i c a l s o f C o n c e r n (c a r c i n o g e n t s ) In d i v i d u a l P o l y n u c l e a r A r o m a t i c H y d r o c a r b o n s ( P A H s ) SSCL.OFV.MW-5 Page 2 of 3 2/21/2024 10:35 AM Page 3 of 3Site-Specific Cleanup Levels* for Commercial/ Industrial Receptors Air Groundwater Soil SSCLair SSCLwing SSCLwesp SSCLwamb SSCLs-leach SSCLsesp SSCLsamb SSCLss (See Eq. D.1)(See Eq. D.2)(See Eq. D.3)(See Eq. D.4)(See Eq. D.5)(See Eq. D.6)(See Eq. D.7)(See Eq. D.8) Air Groundwater Groundwater Groundwater Subsurface soil Subsurface soil Subsurface soil Surface Soil Inhalation Ingestion Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Leaching to groundwater (groundwater ingestion) Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Ingestion of soil, inhalation of vapors and particles, and dermal contact µg/m3 air µg/m3 air mg/L water mg/L water mg/L water mg/L water mg/kg soil mg/kg soil mg/kg soil mg/kg soil mg/kg soil Soil Comments (e.g. Sample ID, Sample Depth, Sample Date, etc.) Highest Soil Concentrations Remaining at the Site Highest Air Concentrations Remaining at the Site Air Comments (e.g. Sample ID, Sample Date, etc.) Groundwater Comments (e.g. Sample ID, Sample Date, etc.)Chemical Name (CAS #) Pr i m a r y C h e m i c a l s o f C o n c e r n Highest Groundwater Concentrations Remaining at the Site Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used * - Site-Specific Cleanup Levels assume a Natural Attenuation Factor of 1 (i.e. no natural attenuation). c - carcinogen; nc - non-carcinogen Site-specific Parameters used in Calculations Parameter Comments Soil Receptor i Lgw Ls Pavement Precip. Soil Zone W inches/year Not applicable ft Units Not applicable Not applicable ft-vertical/ft-lateral ft Not applicable ft MW-5 MW-5 20 Yes 120 Value Silty sand Commercial/ Industrial 0.03 14 12 PAVED: contamination beneath pavement Depth to groundwater Hydraulic gradient Select the most sensitive Receptor that is present at the site Soil type representative of site Description Width of contaminated source area parallel to groundwater flow or wind direction Annual precipitation Is contamination present in the saturated zone? Is contamination beneath pavement or bare soils? Depth to contaminated soil Ad d i t i o n a l C h e m i c a l s o f C o n c e r n (n o n - c a r c i n o g e n t s ) SSCL.OFV.MW-5 Page 3 of 3 2/21/2024 10:35 AM ATTACHMENT B2 SSCL at MW-8 Page 1 of 3SSCL Calculator Prepared for:SSCL Calculator Prepared by: Site name: Site address: Facility ID: Release ID: Contact name: Contact phone: Contact e-mail: Site-Specific Cleanup Levels* for Commercial/ Industrial Receptors Air Groundwater Soil SSCLair SSCLwing SSCLwesp SSCLwamb SSCLs-leach SSCLsesp SSCLsamb SSCLss (See Eq. D.1)(See Eq. D.2)(See Eq. D.3)(See Eq. D.4)(See Eq. D.5)(See Eq. D.6)(See Eq. D.7)(See Eq. D.8) Air Groundwater Groundwater Groundwater Subsurface soil Subsurface soil Subsurface soil Surface Soil Inhalation Ingestion Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Leaching to groundwater (groundwater ingestion) Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Ingestion of soil, inhalation of vapors and particles, and dermal contact µg/m3 air µg/m3 air mg/L water mg/L water mg/L water mg/L water mg/kg soil mg/kg soil mg/kg soil mg/kg soil mg/kg soil Benzene (71-43-2)c 4.93E-01 0.297 SG-1 7/28/2011 (slab atten. factor *0.03)9.87E-03 7.23E-01 1.25E+02 0.005 MW-8 2.57E-01 3.99E-03 1.74E-01 5.33E+00 0.01 MW-8@16' Toluene (108-88-3)nc 7.31E+03 1.291 SG-1 7/28/2011 (slab atten. factor *0.03)8.18E+00 1.21E+04 2.11E+06 0.012 MW-8 3.42E+02 8.00E+01 3.50E+03 5.38E+03 0.03 MW-8@16' Ethylbenzene (100-41-4)nc 1.48E+03 0.150 SG-1 7/28/2011 (slab atten. factor *0.03)1.02E+01 2.69E+03 4.70E+05 0.012 MW-8 7.44E+02 2.47E+01 1.08E+03 6.31E+03 0.03 MW-8@16' Xylenes (1330-20-7)nc 1.48E+02 0.571 SG-1 7/28/2011 (slab atten. factor *0.03)2.04E+01 2.38E+02 4.14E+04 0.012 MW-8 1.51E+03 3.39E+00 1.48E+02 5.22E+03 0.03 MW-8@16' Naphthalene (91-20-3)nc 4.39E+00 0.300 SG-1 7/28/2011 (slab atten. factor *0.03)2.04E+00 1.30E+01 1.65E+03 0.032 MW-8 1.83E+02 2.36E+00 1.03E+02 2.45E+02 0.03 MW-8@16' MTBE (1634-04-04)nc 4.38E+03 0.150 SG-1 7/28/2011 (slab atten. factor *0.03)5.11E-01 3.26E+03 2.28E+05 0.005 MW-8 6.56E+00 1.81E+02 7.94E+03 3.40E+02 0.01 MW-8@16' Alkyl benzenes (C9-C10) [average values]nc 3.07E+02 4.09E+00 5.78E+02 1.01E+05 6.53 MW-8 5.80E+02 1.06E+01 4.64E+02 2.36E+03 0 MW-8@16' Alkyl naphthalenes (C11-C13) [average values]nc 3.07E+02 4.09E+00 8.67E+02 1.12E+05 5.4 MW-8 2.72E+03 1.14E+03 4.97E+04 9.53E+03 62 MW-8@16' Total PAHs (C12-C22) [average values]nc 1.53E+02 3.07E+00 1.41E+02 2.33E+04 5.4 MW-8 1.80E+04 4.14E+02 1.81E+04 5.62E+03 62 MW-8@16' Aliphatics (C5-C6) [Hexane (110-54-3)]nc 3.07E+02 0.270 SG-1 7/28/2011 6.13E+00 5.08E+02 9.05E+04 6.53 MW-8 8.93E+03 7.80E-01 3.41E+01 3.31E+03 0 MW-8@16' Aliphatics (C7-C8) [Heptane (142-82-5)]nc 3.07E+02 0.282 SG-2 1/10/2013 (slab atten. factor *0.03)6.13E+00 6.14E+02 1.10E+05 6.53 MW-8 1.78E+04 1.06E+00 4.65E+01 3.31E+03 0 MW-8@16' Aliphatics (C9-C10) [Nonane (111-84-2)]nc 1.48E+03 0.390 SG-2 1/10/2013 (slab atten. factor *0.03)1.02E+01 3.47E+03 6.18E+05 6.53 MW-8 8.54E+04 7.38E+00 3.23E+02 6.31E+03 0 MW-8@16' Aliphatics (C11-C12) [Undecane (1120-21-4)]nc 1.48E+03 1.02E+01 3.94E+03 7.03E+05 5.4 MW-8 3.55E+05 4.29E+01 1.88E+03 6.31E+03 62 MW-8@16' Aliphatics (C13-C16) [Hexadecane (544-76-3)]nc 1.48E+03 1.02E+01 4.55E+03 8.11E+05 5.4 MW-8 4.79E+06 6.76E+02 2.96E+04 6.31E+03 62 MW-8@16' Aliphatics (C17-C21) [Heptadecane (629-78-7)]nc 1.02E+04 2.04E+02 3.75E+04 6.69E+06 5.4 MW-8 7.58E+09 6.45E+05 2.82E+07 1.26E+05 62 MW-8@16' Aliphatics (C22-C35) [Heptadecane (629-78-7)]nc 1.02E+04 2.04E+02 3.75E+04 6.69E+06 5.4 MW-8 7.58E+09 6.45E+05 2.82E+07 1.26E+05 62 MW-8@16' Highest Air Concentrations Remaining at the Site Air Comments (e.g. Sample ID, Sample Date, etc.) Groundwater Comments (e.g. Sample ID, Sample Date, etc.)Chemical Name (CAS #) Pr i m a r y C h e m i c a l s o f C o n c e r n To t a l P e t r o l e u m H y d r o c a r b o n F r a c t i o n s Highest Groundwater Concentrations Remaining at the Site Soil Comments (e.g. Sample ID, Sample Depth, Sample Date, etc.) Highest Soil Concentrations Remaining at the Site Name: Company, Agency, other: Phone: E-mail: UST Consultant Cert. #: Mark Crim DEQ/ERR Date prepared:1/20/2024 South Washington Plaza 3965 South washington Blvd., South Ogden, Utah 1200678 OFV SSCL.OFV.MW-8 Page 1 of 3 2/21/2024 10:36 AM Page 2 of 3Site-Specific Cleanup Levels* for Commercial/ Industrial Receptors Air Groundwater Soil SSCLair SSCLwing SSCLwesp SSCLwamb SSCLs-leach SSCLsesp SSCLsamb SSCLss (See Eq. D.1)(See Eq. D.2)(See Eq. D.3)(See Eq. D.4)(See Eq. D.5)(See Eq. D.6)(See Eq. D.7)(See Eq. D.8) Air Groundwater Groundwater Groundwater Subsurface soil Subsurface soil Subsurface soil Surface Soil Inhalation Ingestion Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Leaching to groundwater (groundwater ingestion) Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Ingestion of soil, inhalation of vapors and particles, and dermal contact µg/m3 air µg/m3 air mg/L water mg/L water mg/L water mg/L water mg/kg soil mg/kg soil mg/kg soil mg/kg soil mg/kg soil Highest Air Concentrations Remaining at the Site Air Comments (e.g. Sample ID, Sample Date, etc.) Groundwater Comments (e.g. Sample ID, Sample Date, etc.)Chemical Name (CAS #) Pr i m a r y C h e m i c a l s o f C o n c e r n Highest Groundwater Concentrations Remaining at the Site Soil Comments (e.g. Sample ID, Sample Depth, Sample Date, etc.) Highest Soil Concentrations Remaining at the Site Acenaphthylene (208-96-8)nc 1.53E+02 3.07E+00 1.45E+03 1.01E+05 8.21E+02 1.69E+03 7.39E+04 6.19E+03 Acenaphthene (83-32-9)nc 8.69E+01 6.13E+00 6.33E+02 4.85E+04 1.42E+03 5.98E+02 2.61E+04 4.28E+03 Fluorene (86-73-7)nc 5.62E+01 4.09E+00 6.53E+02 4.16E+04 1.52E+03 1.12E+03 4.89E+04 4.05E+03 Phenanthrene (85-01-8)nc 1.53E+02 3.07E+00 4.29E+03 2.24E+05 2.35E+03 1.66E+04 7.27E+05 1.05E+04 Anthracene (120-12-7)nc 4.38E+02 3.07E+01 1.03E+04 5.53E+05 2.22E+04 3.74E+04 1.64E+06 5.35E+04 Fluoranthene (206-44-0)nc 5.83E+01 4.09E+00 5.32E+03 2.47E+05 1.06E+04 7.27E+04 3.18E+06 1.39E+04 Pyrene (129-00-0)nc 4.38E+01 3.07E+00 4.97E+03 2.26E+05 7.34E+03 6.32E+04 2.77E+06 1.07E+04 Benz(a)Anthracene (56-55-3)c 1.96E-01 3.92E-04 1.86E+01 8.47E+02 3.71E+00 9.39E+02 4.11E+04 2.00E+00 Chrysene (218-01-09)c 1.96E+00 3.92E-02 4.87E+02 2.17E+04 2.96E+02 1.97E+04 8.64E+05 1.91E+02 Benzo(b)Fluoranthene (205-99-2)c 1.96E-02 3.92E-04 1.22E+00 5.93E+01 3.02E+00 4.88E+01 2.13E+03 1.82E+00 Benzo(k)-Fluoranthene (207-08- 09)c 1.96E-01 3.92E-03 8.11E+02 3.52E+04 4.40E+01 4.93E+04 2.15E+06 1.99E+01 Benzo(a)-Pyrene (50-32-8)c 2.35E-03 3.92E-05 2.65E+00 1.15E+02 4.77E-01 1.74E+02 7.60E+03 1.98E-01 Indeno(1, 2, 3-Cd)Pyrene (193-39- 5)c 2.35E-02 3.92E-04 1.39E+03 1.25E+04 2.95E-01 5.66E+03 5.12E+04 1.97E+00 Dibenzo-(a, h)Anthracene (53-70- 3)c 2.35E-02 3.92E-04 6.10E+01 2.65E+03 2.69E+01 2.27E+04 9.91E+05 2.00E+00 Benzo (g, h, i)-Perylene (191-24-2)nc 1.53E+02 3.07E+00 1.08E+05 4.74E+06 8.85E+04 1.68E+07 7.37E+08 1.55E+04 Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not used Not used c Not used Not used Not used Not used Not used Not used Not used Not usedAd d i t i o n a l C h e m i c a l s o f C o n c e r n (c a r c i n o g e n t s ) In d i v i d u a l P o l y n u c l e a r A r o m a t i c H y d r o c a r b o n s ( P A H s ) SSCL.OFV.MW-8 Page 2 of 3 2/21/2024 10:36 AM Page 3 of 3Site-Specific Cleanup Levels* for Commercial/ Industrial Receptors Air Groundwater Soil SSCLair SSCLwing SSCLwesp SSCLwamb SSCLs-leach SSCLsesp SSCLsamb SSCLss (See Eq. D.1)(See Eq. D.2)(See Eq. D.3)(See Eq. D.4)(See Eq. D.5)(See Eq. D.6)(See Eq. D.7)(See Eq. D.8) Air Groundwater Groundwater Groundwater Subsurface soil Subsurface soil Subsurface soil Surface Soil Inhalation Ingestion Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Leaching to groundwater (groundwater ingestion) Indoor air (enclosed space) vapor inhalation Outdoor air (ambient) vapor inhalation Ingestion of soil, inhalation of vapors and particles, and dermal contact µg/m3 air µg/m3 air mg/L water mg/L water mg/L water mg/L water mg/kg soil mg/kg soil mg/kg soil mg/kg soil mg/kg soil Highest Air Concentrations Remaining at the Site Air Comments (e.g. Sample ID, Sample Date, etc.) Groundwater Comments (e.g. Sample ID, Sample Date, etc.)Chemical Name (CAS #) Pr i m a r y C h e m i c a l s o f C o n c e r n Highest Groundwater Concentrations Remaining at the Site Soil Comments (e.g. Sample ID, Sample Depth, Sample Date, etc.) Highest Soil Concentrations Remaining at the Site Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used Not used nc Not used Not used Not used Not used Not used Not used Not used Not used * - Site-Specific Cleanup Levels assume a Natural Attenuation Factor of 1 (i.e. no natural attenuation). c - carcinogen; nc - non-carcinogen Site-specific Parameters used in Calculations Parameter Comments Soil Receptor i Lgw Ls Pavement Precip. Soil Zone W Ad d i t i o n a l C h e m i c a l s o f C o n c e r n (n o n - c a r c i n o g e n t s ) Width of contaminated source area parallel to groundwater flow or wind direction Annual precipitation Is contamination present in the saturated zone? Is contamination beneath pavement or bare soils? Depth to contaminated soil Depth to groundwater Hydraulic gradient Select the most sensitive Receptor that is present at the site Soil type representative of site Description 20 Yes 120 Value Silty sand Commercial/ Industrial 0.03 17.79 16 PAVED: contamination beneath pavement MW-8 MW-8 inches/year Not applicable ft Units Not applicable Not applicable ft-vertical/ft-lateral ft Not applicable ft SSCL.OFV.MW-8 Page 3 of 3 2/21/2024 10:36 AM