Southern Maryland Wood Treating
Soil Treatment Progress
- To date, approximately 60,000 tons of contaminated soil have been excavated from Pits 1, 2, and 3 and treated in the onsite Thermal Desorption Units (TDUs). Excavation in these pits is expected to be completed in early February 1999.
- Sixty-thousand tons is approximately 40 percent of the total volume of soil estimated to be excavated from the entire site, and about twice the volume estimated for Pits 1, 2 and 3. The excavation was expanded laterally after unanticipated debris was discovered buried along the perimeter of the three pits.
- Sampling results verified that all soil treated to date has met EPA's established cleanup levels.
- Clean, treated soil is currently being backfilled into Pit 1 and Pit 2.
- Pit 4 excavation will begin in February 1999. Approximately 100,000 tons of contaminated soil will be removed from this pit and treated in the onsite TDUs.
- A dewatering system was recently installed within the sheet pile wall surrounding Pit 4. The dewatering system consists of a series of connected well points and wells. Because the Pit 4 excavation will be deep, the dewatering system will be needed to collect excess groundwater and transfer it to the onsite water treatment systems.
- Excavation, treatment and backfilling of all contaminated soil should be completed by the Fall of 1999.
Water Treatment Systems
- The two onsite water treatment systems continue to treat water from the onsite pond and water generated in the vapor recovery systems of the TDUs.
- In February, the water treatment systems will begin treating groundwater that is generated in the dewatering process from Pit 4.
- All treated water from the two systems is currently recycled back to the thermal desorption process. The water is used to cool the gases generated in the TDU systems and to rehydrate treated soil which is very dry when it comes out of the TDUs.
Other Site Happenings
- The Proof of Performance Report (October 1998), which presents the results of tests conducted on the TDUs prior to start-up, is available for review in the site file located at the St. Mary's County Memorial Library.
- Regular air monitoring conducted at the site perimeter confirms that no harmful emissions of dust or other contaminants are migrating offsite.
- Quarterly groundwater sampling shows no degradation of groundwater quality in the deeper aquifer which lies below a clay confining layer.
The Southern Maryland Wood Treating (SMWT) Site operated as a wood treating facility from 1965 until 1978. These operations resulted in creosote and pentachlorophenol contamination in soil and groundwater at the site.
In 1986, the U.S. Environmental Protection Agency (EPA) placed the abandoned SMWT property on the National Priorities List, making it eligible for federal funding to study and clean the property. The first phase of cleanup began in 1988. After extensive studies by EPA and the Maryland Department of the Environment (MDE), and in collaboration with local residents and officials, a final cleanup plan was selected in 1995.
Construction work began in 1998 and is ongoing under oversight of EPA, MDE, and the U.S. Army Corps of Engineers (USACE). Cleanup is expected to be completed in 1999. This fact sheet provides a brief update of ongoing work, milestones and other site-related happenings.
Additional Site Information
For further information about the SMWT Site, please contact:
Carrie Deitzel (3HS43)
EPA Community Involvement Coordinator
1650 Arch Street
Philadelphia, PA 19103
(800) 553-2509 (215) 814-5525 firstname.lastname@example.org
USACE Project Manager
To review site documents:
St. Mary's County Library
23250 Hollywood Road
Leonardtown, MD 20650