Drycleaner Site Profiles

Former Colony Cleaners, Richardson, Texas

Description
Historical activity that resulted in contamination.

Drycleaning operations at the site were initiated between 1975 and 1980 and continued until 1999. Contamination was discovered in 1999. The contaminant source area is located at the former location of the drycleaning machine.

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


Contaminant Media Concentration (ppb) Nondetect
cis-1,2-Dichloroethene groundwater 3,850 ppb
cis-1,2-Dichloroethene soil 400 ppb
No corresponding contaminant groundwater 6 ppb
ethylbenzene soil 40 ppb
Tetrachloroethene (PCE) groundwater 630 ppb
Tetrachloroethene (PCE) soil 7,400 ppb
Trichloroethene (TCE) groundwater 2,600 ppb
Trichloroethene (TCE) soil 840 ppb
trans-1,2-Dichloroethene groundwater 180 ppb
Vinyl Chloride groundwater 8 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:  
Plume Size:  
Average Depth to Groundwater:   14ft

Lithology and Subsurface Geology

 
  clay
Depth: 0-15ft bgs
15ft thick
Conductivity: 0.0361ft/day
Gradient: 0.0037ft/ft
 
  Limestone (Austin Chalk)
Depth: 15ft bgs

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
DNAPL Present

Remediation Scenario

Cleanup Goals:
 

Technologies

In Situ Other
 

Why the technology was selected:
The presence of PCE degradation products indicated that reductive dechlorination has occurred. HRC was utilized to stimulate biodegradation at the site.

Date implemented:
A single injection event of HRC occured in October 2000.

Final remediation design:
HRC was injected at depths of 6-12 ft bgs via direct push at 5 locations upgradient of the contaminant source area. Four lbs/ft were injected for a total of 50 pounds/injection point (total of 250 pounds).

Results to date:
Contaminant concentrations in groundwater in the contamiant source area have decreased since the October 2000 injection event: Source area monitoring well -- from 630 µg/l PCE (February 2001) to 253 µg/l PCE (April 2003). Downgradient monitoring well -- from 50 µg/l PCE (September 2002) to 24 µg/l PCE (April 2003).

Next Steps:
Continued groundwater monitoring was recommended at the site.

Costs

Cost for Assessment:
  No cost data is available.
Cost for Operation and Maintenance:
 
Total Costs for Cleanup:
 

Contacts

Peter Wehner
Texas Commission on Environmental Quality (TCEQ)
Voluntary Cleanup Program
12100 Park Circle, Bldg. D
Austin, Texas 78753

HKC & Associates, Inc.
2995 LBJ Freeway, Suite 132
Dallas, Texas 75234