Site Narrative:
In November 1994, KDHE conducted a geoprobe investigation in the Gilbert & Mosley Site, which included the Tri-State Laundry Facility (Tri-State), located at 724 East Osie Road. Results from the investigation indicated high concentrations of PCE (130 mg/L) in a puddle and elevated levels of PCE ranging from 1.3 to 19 mg/L in shallow groundwater. KDHE issued an Administrative Order to Tri-State Laundry and Dry Cleaner Supply, Inc. on June 24, 1998 to investigate their facility. Tri-State challenged the order, and additional investigation was conducted associated with a lawsuit, which confirmed the facility was a source of VOC contamination. Tri-State declared bankruptcy, leaving the City of Wichita responsible for investigation and remediation.
A source area investigation was conducted in 2002 by the City of Wichita. Since the Harcros and Tri-State facility source areas are adjacent to each other, the City is working the sites together. A draft Source Area Investigation Report and a Source Control Measures Report were submitted to KDHE for these source areas on in 2003.
Due to the relatively high concentrations of soil contamination present at the Harcros/Tri-State source areas, KDHE conducted indoor air sampling at adjacent residences. The indoor air results suggest that the contamination at the sites is potentially impacting indoor air quality; however, the concentrations in indoor air were not above current health risk values. Additional indoor air sampling was performed during the winter and spring of 2005, along with a soil gas/groundwater investigation to delineate the down-gradient plume.
In September 2005, two vapor mitigation systems were installed in houses in the neighborhood. PCE was detected above proposed mitigation levels in the basement of one of the houses, while the other was offered to the resident by the City of Wichita. In February 2006, off-site excavations of soil above the soil-to-groundwater pathway Risk-Based Standard for Kansas level for PCE were performed. An air sparge/soil vapor AS/SVE extraction system design was installed in 2007.
Confirmation sampling to determine effectiveness of the AS/SVE system on groundwater contaminant levels and soil concentrations was performed in 2011 and 2012. An optimization plan to improve the effectiveness of the AS/AVE system was approved by KDHE in 2012. The current operation includes pulsed SVE to increase removal of source contaminants from the soil zone. The AS system is still operational to address groundwater contamination.
Optimized AS/SVE system in use at site. Semi-annual sampling will continue to determine if new system is working well. Operation and maintenance of remedial system overseen by City of Wichita as of spring 2014. Chemical results will be evaluated from June and November 2015 sampling events to determine if a rebound test can be run at the site.
A rebound assessment began October 30, 2018, with the AS/SVE system to be shut down for a period of 6 months. An evaluation of results after the 6 month period determined the system could be permanently shut off. |