Site Number: |
B4C1 |
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Contract Number: |
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D.O. Number: |
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Action Memo Date: |
6/9/2014 |
Response Authority: |
CERCLA |
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Response Type: |
PRP Oversight |
Response Lead: |
EPA |
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Incident Category: |
Removal Action |
NPL Status: |
Non NPL |
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Operable Unit: |
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Mobilization Date: |
11/3/2014 |
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Start Date: |
11/3/2014 |
Demob Date: |
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Completion Date: |
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CERCLIS ID: |
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RCRIS ID: |
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ERNS No.: |
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State Notification: |
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FPN#: |
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Reimbursable Account #: |
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1.1.1 Site Description
The Virginia-Carolina Chemical Company Mobile Site (the Site) is located in Prichard, Mobile County, Alabama. The Site is a former fertilizer production plant which occupied approximately 24 acres and was operated by the Virginia-Carolina Chemical (VCC) Company. Fertilizer manufacturing began at the Site prior to 1895 and continued until 1961.
VCC acquired the Mobile fertilizer plant from Mobile Phosphate Company between 1895 and 1904 and operated the plant until declaring bankruptcy in 1924. VCC of Richmond, Virginia, emerged from the bankruptcy as a new company and continued to operate the fertilizer plant until 1961. VCC merged into Socony Mobil Oil Company, Inc., in 1963 and the company changed names in 1966 to Mobil Oil Corporation. In 1999, Exxon Corporation merged with Mobil Oil Corporation. ExxonMobil Oil Corporation is the corporate successor to this VCC site.
1.2 Site Location
Most of the former VCC property was located within the current I-165 corridor and the original plant structures no longer exist. The I-165 corridor consists of an elevated six-lane freeway deck with frontage roads on both the northeast and southwest sides of the interstate. Structures associated with the former plant include a fertilizer mixing and storing area, acid chambers with associated burners/furnaces, a sulfur heap, a bag house, a boiler room, an oil house, a potash storage building, an ammonia tank house, and several electrical transformers.
1.1.2.2 Description of Threat
In July 2000, the US Environmental Protection Agency (EPA) Region 4 began working with Exxon Mobil Corporation to resolve outstanding environmental issues associated with former operations of the former VCC fertilizer plants. A total of 40 former VCC facilities were identified and prioritized throughout the eight southeastern states that comprise EPA Region 4.
In May 2010, ExxonMobil's contractor (ARCADIS) conducted a Removal Site Evaluation (RSE) at the VCC Mobile Site. A total of 98 soil samples were collected from 32 soil boring locations across the Site. Samples were collected from 0.0 to 0.5 feet below ground surface (bgs), 0.5 to 2 feet bgs, and 2 to 4 feet bgs. Four surface water samples and four sediment samples were also collected from the drainage ditch that traverses the Site. All samples were analyzed for arsenic and lead and the results compared to Site Specific Screening Levels (SSSL) for arsenic (27 ppm) and lead (800 ppm). The SSSLs have been used as remediation endpoints at other former VCC fertilizer sites and meet EPA’s Removal Management Levels for arsenic (240 ppm) and lead (800 ppm) for an industrial exposure scenario. Analytical results demonstrated that 15 of the soil samples exceeded the SSSL for arsenic (27 ppm) and that 5 of the soil samples exceeded the SSSL for lead (800 ppm). The maximum arsenic and lead concentrations detected in the soil samples were 294 ppm and 8,350 ppm, respectively. The depth of impacted soil varied from 0.0 to 4 feet bgs across the Site.
In 2012, ARCADIS returned to the Site and collected an additional 178 soil samples from 55 soil boring locations. The soil samples were collected from 0.0 to 0.5 feet bgs, 0.5 to 2 feet bgs, 2 to 4 feet bgs, and at 2 foot intervals thereafter until XRF screening results for arsenic and lead were below SSSLs. A total of 12 sediment samples and 6 groundwater samples were also collected.
Between the 2010 and 2012 investigations, a total of 276 soil samples from 87 soil borings have been collected from the Site and analyzed for arsenic and lead. A total of 39 soil samples exceeded the SSSL for arsenic and 9 soil samples exceeded the SSSL for lead. The maximum concentration for arsenic and lead in soil was 808 ppm and 18,800 ppm, respectively. Total arsenic concentrations above the groundwater MCL (10 ug/l) was detected in two of the groundwater samples. The concentration of lead detected in the groundwater samples were all below the MCL (15 ug/l) for lead. Because the sediment samples were collected from a wet weather ditch, the results were compared against SSSL for arsenic and lead in soils. Analysis demonstrated that 10 of these samples exceeded the SSSL for arsenic and 5 samples exceeded the SSSL for lead.
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