Drycleaner Site Profiles

Ryan's Express Cleaners, Humble, Texas

Description
Historical activity that resulted in contamination.

Currently inactive, this facility used PCE as its dry cleaning solvent from 1975 to 2008. It was enrolled in the TCEQ DCRP in 2005. Investigations suggest that there was a release of PCE into the soil, most likely through spills.

Remediation Status: In active remediation


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


Contaminant Media Concentration (ppb) Nondetect
cis-1,2-Dichloroethene groundwater 200 ppb
cis-1,2-Dichloroethene soil 51,000 ppb
1,1-Dichloroethene soil 980 ppb
Tetrachloroethene (PCE) groundwater 480 ppb
Tetrachloroethene (PCE) soil 21,000,000 ppb
Trichloroethene (TCE) groundwater 130 ppb
Trichloroethene (TCE) soil 75,000 ppb
Vinyl Chloride soil 3,400 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:   70ft bgs
Plume Size:   Plume Length: 560ft
Plume Width: 240ft
Average Depth to Groundwater:   55ft

Lithology and Subsurface Geology

 
  Sandy clay and clayey sand
Depth: 0-18ft bgs
18ft thick
Gradient: 0.006ft/ft
 
  Mostly dry, loose, fine- to medium-grained sand unit with intermittent clay layers
Depth: 18-55ft bgs
37ft thick
Gradient: 0.006ft/ft
 
  Saturated silty sand- the first GWBU
Depth: 55-70ft bgs
15ft thick
Gradient: 0.006ft/ft
 
  Very stiff, sandy clay layer
Depth: 70-78ft bgs
8ft thick
Gradient: 0.006ft/ft
 
  Fine-grained, loose sand
Depth: 80-112ft bgs
32ft thick
Gradient: 0.006ft/ft
 
  A stiff, sandy clay layer confines the second GWBU.
Depth: 112-115ft bgs
3ft thick
Gradient: 0.006ft/ft

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
DNAPL Present

Vapor Intrusion Pathway

Has the potential for vapor intrusion (VI) been evaluated?
  No
Has a vapor mitigation system been installed?
   

Remediation Scenario

Cleanup Goals:
  Reduce COC contaimnation levels below MCLs. Reduce overal media concentration in soils to eliminate continued leaching of the constituents of concern from soil to the first GWBU
Remedy Level:
  Interim Action

Technologies

In Situ Air Sparging
 

Date implemented:
April 2011

Final remediation design:
A combination SVE and air sparge
remediation system consisting of nine
vapor recovery wells and four air sparge wells was installed on site. The wells were installed to a depth of 10 feet which is where the majority of soil impact was identified. The system
opperated continually for 6 months.

Results to date:
A mass of approximately 56 pounds of chlorinated volatile organic compounds were removed from the site from 27.55 million cubic feet of air. Post remediation analysis revealed that the highest concetration of PCE discovered in soil was 15.2 mg/kg as compared to the initial concentration of 21,000 mg/kg. No samples reported TCE above applicable PCL. Cis-1,2-DCE, trans1,2-DCE, 1,1-DCE and VC were reported at concentrations near or less than the laboratory detection limits in soil samples. A significant reduction in the areal extent of soil impact has occured as a result of the soil response action.

Next Steps:
Because PCE levels remain above the PCL, operation of the SVE system will contine. Once the soil PCLE zone is eliminated, future leaching to groundwater will be removed.
Developing a plan of action to implement groundwater response action in the near future.
Continued regular groundwater monitoring to assess movement of the impacted groundwater plume.

Cost to Design and Implement:
$130,000

In Situ Soil Vapor Extraction
 

Why the technology was selected:
SVE was the best option for this site because it allowed soil to be decontaminated while working around existing infastructure.

Date implemented:
April 2011

Final remediation design:
A combination SVE and air sparge
remediation system consisting of nine
vapor recovery wells and four air sparge wells was installed on site. The wells were installed to a depth of 10 feet which is where the majority of soil impact was identified. The system
opperated continually for 6 months.

Results to date:
A mass of approximately 56 pounds of chlorinated volatile organic compounds were removed from the site from 27.55 million cubic feet of air. Post remediation analysis revealed that the highest concetration of PCE discovered in soil was 15.2 mg/kg as compared to the initial concentration of 21,000 mg/kg. No samples reported TCE above applicable PCL. Cis-1,2-DCE, trans1,2-DCE, 1,1-DCE and VC were reported at concentrations near or less than the laboratory detection limits in soil samples. A significant reduction in the areal extent of soil impact has occured as a result of the soil response action.

Next Steps:
Because PCE levels remain above the PCL, operation of the SVE system will contine. Once the soil PCLE zone is eliminated, future leaching to groundwater will be removed.
Developing a plan of action to implement groundwater response action in the near future.
Continued regular groundwater monitoring to assess movement of the impacted groundwater plume.

Cost to Design and Implement:
$130,000

Costs

Cost for Assessment:
  $259,000
Cost for Operation and Maintenance:
 
Total Costs for Cleanup:
 

Lessons Learned

Due to the noise of the SVE system, it could only run at night. Piping and SVE points inside the building limited the use of for the tenant.

Contacts

Dan Switek, P.G.
Project Manager
Remediation Division
Texas Commission on Environmental Quality
12100 Park 35 Circle, MC-137
Austin, TX 78753
phone: (512) 239-4132

Site Specific References

Affected Property Assessment Report
Field Activities Report
Monitoring Reports