Drycleaner Site Profiles

Former Bunny Cleaners, Memphis, Tennessee

Description
Historical activity that resulted in contamination.

A 2,647 sq. ft. drycleaning facility operated from 1975 to 1997 on the site. The drycleaner was located in a multi-tenant, multi-building strip mall. The source area has been identified in the rear of the building along the east wall of the site building. The drycleaning facility used PCE as its only solvent. The property is surrounded on three sides by commercial properties and to the north a residential area exists.

Remediation Status: In groundwater monitoring


Contaminants
Contaminants present and the highest amount detected in both soil and groundwater.


Contaminant Media Concentration (ppb) Nondetect
cis-1,2-Dichloroethene groundwater
cis-1,2-Dichloroethene soil
Tetrachloroethene (PCE) groundwater
Tetrachloroethene (PCE) soil
Trichloroethene (TCE) groundwater
Trichloroethene (TCE) soil
Vinyl Chloride groundwater
Vinyl Chloride soil

Site Hydrology

Deepest Significant Groundwater Contamination:   32ft bgs
Plume Size:  
Average Depth to Groundwater:   28ft

Lithology and Subsurface Geology

 
  silty clay loam
Depth: 0-20ft bgs
20ft thick
Conductivity: 8.96E-005ft/day
Gradient: 0.019ft/ft
 
  silty clay
Depth: 20-23ft bgs
3ft thick
 
  sandy clay loam
Depth: 23-27ft bgs
4ft thick
 
  sandy loam
Depth: 27-36ft bgs
9ft thick

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
checkPresumptive Evidence of DNAPL

Vapor Intrusion Pathway

Has the potential for vapor intrusion (VI) been evaluated?
  Yes
How was the site evaluated?
 
Results of VI evaluation:
  The VI pathway was ruled out (or does not exist)
Has a vapor mitigation system been installed?
  No 
Additional VI Information:
  The VI Pathway was evaluated and no risk was identified.

Remediation Scenario

Cleanup Goals:
  To achieve drinking water standards, with an interim goal of plume contraction.
Remedy Level:
  Full Scale Remedy

Technologies

In Situ Biostimulation
 

Why the technology was selected:
Biostimulation and zero valent iron (ZVI) was recommended by Innovative Environmental Technologies and selected in 2009 in order to stimulate the reductive dechlorination of PCE. The concentration of PCE's anaerobic reaction products were such that biological reductive dechlorination was occurring, but needed to be stimulated.

Date implemented:
Winter 2007- Biostimulation Winter 2009- Biostimulation and ZVI

Final remediation design:
As an interim action, an excavation of approximately 63 tons of soil occurred at the site, with the excavated soil disposed of as hazardous waste. The excavated soil source area was identified through investigations to be in the loading dock area/ back door of the former drycleaner. The excavation was 30 ft x 8 ft x 8 ft deep. An infiltration gallery was installed into the excavation pit prior to backfilling. A second interim action was designed and implemented by the environmental consultant in early Winter 2007. An area 45 ft x 75 ft x 15 ft deep was treated using the existing infiltration gallery plus 15 additional direct push points. The infiltration gallery was loaded with approximately 360 gallons of emulsified oil and the fifteen injection points were loaded with 500 gallons of emulsified oil (approximately 33 gallons per point). A final remedial design was designed and implemented by Innovative Environmental Technologies in early winter 2009. An area of 12,850 square feet was treated using a solution of approximately 2,750 pounds of ZVI, 600 pounds of calcium propionate, 400 pounds of yeast extract, 200 pounds of an oxygen scavenger, 200 pounds of nutrient, vitamins B2 and B12, 750 pounds of HRC, and 5,400 pounds of EHC using 20 direct push points.

Results to date:
Groundwater sampling at the Bunny Cleaner's site has occurred quarterly across the site with specific monitoring wells sampled each time. The pre- and post-remedial PCE concentrations are displayed below from the early Winter 2009 injection event. The most significant reductions occurred in monitoring well MW-9 which is located in the source area. PCE Well March 08(pre) May 09 (post) MW-3 880ppb 513ppb MW-6 25ppb 10.6ppb MW-7 320ppb 370ppb Monitoring well MW-9 Feb 08 (pre) Sep 09 (post) PCE 13,000 ppb 35 ppb TCE 1,400 ppb 8.05 ppb cis-DCE 3,300 ppb 1,500 ppb VC 320 ppb 1,740 ppb

Next Steps:
Two more groundwater sampling events are scheduled over the upcoming 120 days.

Cost to Design and Implement:
-emulsified oil injection-$180,291 -Bio/Abiotic injection-$107,514

In Situ Zero Valent Iron
 

Why the technology was selected:
Biostimulation and zero valent iron (ZVI) was recommended by Innovative Environmental Technologies and selected in 2009 in order to stimulate the reductive dechlorination of PCE. The concentration of PCE's anaerobic reaction products were such that biological reductive dechlorination was occurring, but needed to be stimulated.

Date implemented:
Winter 2007- Biostimulation Winter 2009- Biostimulation and ZVI

Final remediation design:
As an interim action, an excavation of approximately 63 tons of soil occurred at the site, with the excavated soil disposed of as hazardous waste. The excavated soil source area was identified through investigations to be in the loading dock area/ back door of the former drycleaner. The excavation was 30 ft x 8 ft x 8 ft deep. An infiltration gallery was installed into the excavation pit prior to backfilling. A second interim action was designed and implemented by the environmental consultant in early Winter 2007. An area 45 ft x 75 ft x 15 ft deep was treated using the existing infiltration gallery plus 15 additional direct push points. The infiltration gallery was loaded with approximately 360 gallons of emulsified oil and the fifteen injection points were loaded with 500 gallons of emulsified oil (approximately 33 gallons per point). A final remedial design was designed and implemented by Innovative Environmental Technologies in early winter 2009. An area of 12,850 square feet was treated using a solution of approximately 2,750 pounds of ZVI, 600 pounds of calcium propionate, 400 pounds of yeast extract, 200 pounds of an oxygen scavenger, 200 pounds of nutrient, vitamins B2 and B12, 750 pounds of HRC, and 5,400 pounds of EHC using 20 direct push points.

Results to date:
Groundwater sampling at the Bunny Cleaner's site has occurred quarterly across the site with specific monitoring wells sampled each time. The pre- and post-remedial PCE concentrations are displayed below from the early Winter 2009 injection event. The most significant reductions occurred in monitoring well MW-9 which is located in the source area. PCE Well March 08(pre) May 09 (post) MW-3 880ppb 513ppb MW-6 25ppb 10.6ppb MW-7 320ppb 370ppb Monitoring well MW-9 Feb 08 (pre) Sep 09 (post) PCE 13,000 ppb 35 ppb TCE 1,400 ppb 8.05 ppb cis-DCE 3,300 ppb 1,500 ppb VC 320 ppb 1,740 ppb

Next Steps:
Two more groundwater sampling events are scheduled over the upcoming 120 days.

Cost to Design and Implement:
-emulsified oil injection-$180,291 -Bio/Abiotic injection-$107,514

Ex Situ Soil Removal
 

Date implemented:
Winter 2006- Excavation

Final remediation design:
As an interim action, an excavation of approximately 63 tons of soil occurred at the site, with the excavated soil disposed of as hazardous waste. The excavated soil source area was identified through investigations to be in the loading dock area/ back door of the former drycleaner. The excavation was 30 ft x 8 ft x 8 ft deep. An infiltration gallery was installed into the excavation pit prior to backfilling. A second interim action was designed and implemented by the environmental consultant in early Winter 2007. An area 45 ft x 75 ft x 15 ft deep was treated using the existing infiltration gallery plus 15 additional direct push points. The infiltration gallery was loaded with approximately 360 gallons of emulsified oil and the fifteen injection points were loaded with 500 gallons of emulsified oil (approximately 33 gallons per point). A final remedial design was designed and implemented by Innovative Environmental Technologies in early winter 2009. An area of 12,850 square feet was treated using a solution of approximately 2,750 pounds of ZVI, 600 pounds of calcium propionate, 400 pounds of yeast extract, 200 pounds of an oxygen scavenger, 200 pounds of nutrient, vitamins B2 and B12, 750 pounds of HRC, and 5,400 pounds of EHC using 20 direct push points.

Results to date:
Groundwater sampling at the Bunny Cleaner's site has occurred quarterly across the site with specific monitoring wells sampled each time. The pre- and post-remedial PCE concentrations are displayed below from the early Winter 2009 injection event. The most significant reductions occurred in monitoring well MW-9 which is located in the source area. PCE Well March 08(pre) May 09 (post) MW-3 880ppb 513ppb MW-6 25ppb 10.6ppb MW-7 320ppb 370ppb Monitoring well MW-9 Feb 08 (pre) Sep 09 (post) PCE 13,000 ppb 35 ppb TCE 1,400 ppb 8.05 ppb cis-DCE 3,300 ppb 1,500 ppb VC 320 ppb 1,740 ppb

Next Steps:
Two more groundwater sampling events are scheduled over the upcoming 120 days.

Costs

Cost for Assessment:
  $158,162
Cost for Operation and Maintenance:
 
Total Costs for Cleanup:
  $445,967.00

Contacts

Program Manager
TDEC-DoR
Drycleaner Environmental Response Program
401 Church St.
Nashville, TN

Elizabeth Bishop
Innovative Environmental Technologies
6130 Kit Road, Pipersville, PA
www.iet-inc.net
888-721-8283
elizabethbishop@iet-inc.net
615-263-3876