Drycleaner Site Profiles

Fashion Drycleaners, Klamath Falls, Oregon

Description
Historical activity that resulted in contamination.

Located in a commercial district, the inactive Fashion Drycleaners operated from 1966-1988, when a fire destroyed the building. The drycleaner used perchloroethylene (PCE) as a cleaning agent, and stored it in a 220-gal. above-ground tank on the premises. Investigations revealed the presence of soil and groundwater contamination beneath and in the vicinity of the facility. Volatilization of chlorinated solvents from the shallow groundwater has contaminated the indoor air at two nearby occupied buildings. The presence of basement sumps appears to have exacerbated the indoor air contamination. One likely source of VOC contamination is the historic discharge of solvents to the sanitary sewer system, which may have leaked and released solvents to the soil and groundwater. Investigations revealed the presence of large cracks in the building foundation. Any solvents spilled on the floor would have likely drained through the cracks to the subsurface. Although there is no evidence of large solvent releases directly resulting from the 1988 fire, solvents may have been released via firewater runoff to the sanitary and storm sewers, which may then have leaked to the soil. Finally, investigations also suggested that solvents may have been released when the building was demolished.

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 12,000 ppb
1,1-Dichloroethene groundwater 12 ppb
Tetrachloroethene (PCE) groundwater 13,400 ppb
Tetrachloroethene (PCE) soil 12,100,000 ppb
Trichloroethene (TCE) groundwater 2,000 ppb
trans-1,2-Dichloroethene groundwater 170 ppb
Vinyl Chloride groundwater 3 ppb

Site Hydrology

Deepest Significant Groundwater Contamination:  
Plume Size:   Plume Length: 300ft
Average Depth to Groundwater:   8.5ft

Lithology and Subsurface Geology

 
  Brown to gray siltstone. Relatively impermeable and contractors could not use a geoprobe.
Depth: 21-51ft bgs
30ft thick
Conductivity: 8ft/day
Gradient: 0.02ft/ft
 
  Saturated, thinly bedded dark gray sandstone
Depth: 51-61ft bgs
10ft thick
 
  Sediments and sedimentary rock of the Yonna Formation
Depth: 61-225ft bgs
164ft thick
 
  basalt
Depth: 225ft bgs

Pathways and DNAPL Presence

checkGroundwater
Sediments
checkSoil
checkDNAPL Present

Remediation Scenario

Cleanup Goals:
  The Oregon DEQ sought to remove the contaminant mass from the source area and protect or mitigate threats to human health or the environment. The Oregon soil cleanup level for PCE at sites not impacting groundwater is 0.3 mg/kg. This level was applied to the Fashion Drycleaners site.
Remedy Level:
  Interim Action

Technologies

Ex Situ Incineration
 

Why the technology was selected:
Off-site incineration was chosen given the listed waste nature of the soil and concentrations above the LDR/UTS. On-site treatment was not an option given the location of the site (downtown Klamath Falls, nearby daycare, air permitting issues, etc.).

Date implemented:
June 1995

Final remediation design:
Soils containing more than 5.6 mg/kg (the RCRA Universal Treatment Standard for PCE-contaminated soil) were sent off-site as "extremely hazardous" and incinerated. Soils with 0.3-5.6 mg/kg were sent off-site as "hazardous" for landfill disposal (0.3 mg/kg derived from Oregon's conservative health-based levels).

Results to date:
Contractors removed approximately 2,000 tons of contaminated soil containing PCE concentrations exceeding 0.3 mg/kg. Groundwater PCE concentrations have decreased since the 1980s. Peak concentrations decreased from about 13,400 µg/L in 1989 to the most recently measured level (January 1998) of less than 200 µg/L. Some monitoring wells have not shown any significant decrease with time, however. Beneficial water-use analysis and fate-and-transport modeling suggest that current and reasonably likely beneficial groundwater uses in the local area are not threatened by the contamination. Contractors believe that dissolved or residual PCE DNAPL is unlikely to migrate to the deeper basalt aquifer, which is used for drinking water.

Next Steps:
Uncertainties associated with fate-and-transport modeling are leading contractors to conduct periodic monitoring of sump water and selected groundwater monitoring wells in order to assess contaminant concentrations and confirm natural attenuation processes. Baseline human health risk assessments have identified unacceptable levels of contaminants in the indoor air in two nearby buildings. While vapor intrusion has decreased somewhat, additional data is needed, given the uncertainty posed by large building-specific variations in basement construction, ventilation characteristics, and the presence of other contaminants in sump water, such as 1,1-DCE. A pilot study will be implemented to reduce vapor concentrations, and periodic monitoring will be conducted to better characterize the risks.

Cost to Design and Implement:
$1.2 million (soil removal)

Ex Situ Soil Removal
 

Why the technology was selected:
Off-site incineration was chosen given the listed waste nature of the soil and concentrations above the LDR/UTS. On-site treatment was not an option given the location of the site (downtown Klamath Falls, nearby daycare, air permitting issues, etc.).

Date implemented:
June 1995

Final remediation design:
Soils containing more than 5.6 mg/kg (the RCRA Universal Treatment Standard for PCE-contaminated soil) were sent off-site as "extremely hazardous" and incinerated. Soils with 0.3-5.6 mg/kg were sent off-site as "hazardous" for landfill disposal (0.3 mg/kg derived from Oregon's conservative health-based levels).

Results to date:
Contractors removed approximately 2,000 tons of contaminated soil containing PCE concentrations exceeding 0.3 mg/kg. Groundwater PCE concentrations have decreased since the 1980s. Peak concentrations decreased from about 13,400 µg/L in 1989 to the most recently measured level (January 1998) of less than 200 µg/L. Some monitoring wells have not shown any significant decrease with time, however. Beneficial water-use analysis and fate-and-transport modeling suggest that current and reasonably likely beneficial groundwater uses in the local area are not threatened by the contamination. Contractors believe that dissolved or residual PCE DNAPL is unlikely to migrate to the deeper basalt aquifer, which is used for drinking water.

Next Steps:
Uncertainties associated with fate-and-transport modeling are leading contractors to conduct periodic monitoring of sump water and selected groundwater monitoring wells in order to assess contaminant concentrations and confirm natural attenuation processes. Baseline human health risk assessments have identified unacceptable levels of contaminants in the indoor air in two nearby buildings. While vapor intrusion has decreased somewhat, additional data is needed, given the uncertainty posed by large building-specific variations in basement construction, ventilation characteristics, and the presence of other contaminants in sump water, such as 1,1-DCE. A pilot study will be implemented to reduce vapor concentrations, and periodic monitoring will be conducted to better characterize the risks.

Cost to Design and Implement:
$1.2 million (soil removal)

Costs

Cost for Assessment:
  Pre-removal (SI/IRAM), ~$350,000; post removal (RI/FS/RA), $650,000
Cost for Operation and Maintenance:
  $50,000
Total Costs for Cleanup:
 

Lessons Learned

1. Remediation staff debated how to determine whether indoor air volatilization poses unacceptable risks to human health and the environment. It is difficult to effectively measure the risk, and a healthy debate continues regarding the merits of modeling or sampling.
2. Soil removal serves as a cost effective method, but disposal costs can run high with wastes classified as hazardous under RCRA. Remediation contractors may also encounter logistical problems when attempting to dispose such a large mass. Soil vapor extraction operations lasting for three years may serve as a viable alternative. OR permits the discharge of up to 200 pounds/year to the air without treatment.
3. RCRA hazardous waste classification significantly increased the costs of disposal and treatment. Rather than screening the soil, a blanket determination was made to classify the waste as listed hazardous waste. If the waste had been proven to not be hazardous (e.g. contained-out), the soil removal action would have been significantly cheaper. DEQ estimates it would have cost approximately $100,000-300,000 instead of $1.2 million.

Contacts

Katie Robertson, R.G.
Project Manager
Department of Environmental Quality
800 SE Emigrant Ave, Suite 330
Pendleton, OR 97801
541-278-4620
robertson.katie@deq.state.or.us