State Coalition for Remediation of Drycleaners Site Profiles
Mitchell's Formal Wear, Charlotte, North Carolina
Description
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Mitchell' Formal Wear was previously located in a mixed use shopping center, adjacent to residential properties. The facility conducted drycleaning operations using PCE from 1979 to 2001 and petroleum-based solvent from 2001 to 2002, at which time the business stopped operations. Remediation Status: In groundwater monitoring |
Contaminants
Contaminants present and the highest amount
detected in both soil and groundwater.
Contaminant | Media | Concentration (ppb) | Nondetect |
---|---|---|---|
Benzene | groundwater | ||
Benzene | soil | ||
chloroform | groundwater | ||
chloroform | soil | ||
cis-1,2-Dichloroethene | groundwater | ||
1,2-Dichloroethane | groundwater | ||
1,1-Dichloroethene | groundwater | ||
ethylbenzene | groundwater | ||
methylene chloride | groundwater | ||
n-propylbenzene | groundwater | ||
Tetrachloroethene (PCE) | groundwater | ||
Tetrachloroethene (PCE) | soil | ||
1,2,4-trimethylbenzene | groundwater | ||
1,2,4-trimethylbenzene | soil | ||
1,3,5-trimethylbenzene | groundwater | ||
naphthalene | groundwater | ||
naphthalene | soil | ||
Trichloroethene (TCE) | groundwater | ||
Trichloroethene (TCE) | soil | ||
Vinyl Chloride | groundwater | ||
Vinyl Chloride | soil | ||
1,2-Dichloroethene | groundwater |
Site Hydrology
Deepest Significant Groundwater Contamination: | 90ft bgs | |
Plume Size: | Plume Length: 1,550ft Plume Width: 700ft Plume Thickness: 90ft |
|
Average Depth to Groundwater: | 17.8ft |
Lithology and Subsurface Geology
interbedded clayey silt, sandy silt and silty sand which generally coursens with depth Depth: 0-50ft bgs 50ft thick Conductivity: 0.11ft/day Gradient: 0.02ft/ft |
||
granite bedrock Depth: 50ft bgs |
Pathways and DNAPL Presence
Groundwater Sediments Soil Presumptive Evidence of DNAPL |
Vapor Intrusion Pathway
Has the potential for vapor intrusion (VI) been evaluated? |
Yes |
|
How was the site evaluated? |
Soil vapor and/or Sub-slab vapor sampling,Indoor air sampling,Groundwater sampling,Compared sample concentration to screening criteria,Used an exposure screening model |
|
Results of VI evaluation: |
A completed VI pathway has been indentified,A potential VI pathway has been indentified | |
Has a vapor mitigation system been installed? |
Yes | |
Type of Vapor Mitigation System(s): |
HVAC controls/modifications |
|
Additional VI Information: |
Operation of a large fan in the former drycleaning area successfully reduced indoor air concentrations to below acceptable levels. |
Remediation Scenario
Cleanup
Goals: |
Demonstration of plume stability. |
|
Remedy Level: |
Full Scale Remedy |
Technologies
Ex Situ Soil Removal |
Date implemented: Final remediation design: Results to date: Next Steps: Cost to Design and Implement: |
|
In Situ Air Sparging |
Why the technology was selected: Date implemented: Final remediation design: Results to date: Next Steps: Cost to Design and Implement: |
|
In Situ Chemical Oxidation |
Why the technology was selected: Date implemented: Final remediation design: Results to date: Next Steps: Cost to Design and Implement: |
|
In Situ Multi Phase Extraction |
Why the technology was selected: Date implemented: Final remediation design: Results to date: Next Steps: Cost to Design and Implement: |
Costs
Cost
for Assessment: |
$403,552 | |
Cost
for Operation and Maintenance: |
$0 | |
Total
Costs for Cleanup: |
On-going |
Lessons Learned
Direct-push sampling was performed prior to injection to locate source areas and specifically target injection areas. The targeted injection is considered the key to remediation success at this site. It was also found that in tight soils multiple injections reduces the potential for day-lighting issues. |
Contacts
Delonda Alexander, NC DSCA Program, 1646 Mail Service Center, Raleigh, North Carolina 27699-1646, (919) 707-8365, delonda.alexander@ncdenr.gov |
Site Specific References
7/14/2011 Injection Evaluation Report |