Site Narrative:
In 1999 and 2000, GSI on behalf of Globe Engineering Company conducted an investigation regarding the previously detected TCE in groundwater at the Globe Engineering Facility Site (C2-087-00459) . The results from the above investigations indicated the former Cessna Warehouse was also a potential source of TCE groundwater contamination.
In 2001, KDHE performed a SRE at the Harry and St. Paul Site (C2-087-71327) to evaluate if the former Cessna warehouse was a potential source of TCE groundwater contamination. TCE groundwater contamination was detected at 32,100 µg/L and cis-DCE was detected at 179 µg/L exceeding their EPA MCL of 5 µg/L and 70 µg/L, respectively. The TCE and cis-DCE groundwater detections were located south of Harry Street adjacent to the city sanitary sewer. The results of the SRE were not conclusive and SI was conducted in 2007 to identify potential additional TCE groundwater contamination sources.
The 2007 SI consisted of soil, groundwater, and soil gas sample collection for laboratory analysis. TCE and cis-DCE were detected in groundwater at a maximum concentration of 27,900 µg/L and 441 µg/L, respectively, which exceeds their respective MCL values. TCE and cis-DCE were detected at maximum concentrations of 400 µg/kg and 6.5 µg/kg. The detected TCE in soil exceeded the RSK residential/non-residential soil-to-groundwater pathway value of 84.2 µg/kg. The detected cis-DCE was below its RSK residential/non-residential soil-to-groundwater pathway value of 85.9 µg/kg.
In 2007, Globe Engineering Company conducted three excavations and soil sampling along the sanitary sewer on the north side of Harry Street near their property. During this excavation and sampling event TCE was detected in a soil collected from soil above the sewer line at a concentration of 41 µg/kg and below the sewer line at a concentration of 26 µg/kg. The detected TCE soil concentrations are below the RSK residential/non-residential soil-to-groundwater pathway value of 84.2 µg/kg.
In 2008, KDHE conducted indoor air testing for TCE, cis-DCE, trans-1,2-DCE, and vinyl chloride (VC) in five residences along South St. Paul Street. TCE and cis-DCE were detected in samples collected during this investigation and all TCE and cis-DCE detections were below their respective KDHE indoor air RSK values. Based on these results, no vapor mitigation was implemented, and the indoor air sampling effort was not expanded to other residences in the area. However, since the 2008 sampling effort KDHE has revised the indoor air RSK values and the previously detected TCE and cis-DCE exceed the current KDHE RSK value of 2.09 µg/m3.
In 2010, KDHE requested Cessna enter into a CAFO to conduct a CI. During this investigation TCE and cis-DCE were detected in groundwater at a maximum concentration of 440 µg/L and 124 µg/L, respectively, which exceeds their respective MCL values. TCE was detected in soil at a maximum concentration of 35.5 µg/kg which is below its RSK value for residential/non-residential soil-to-groundwater pathway value of 84.2 µg/kg. Groundwater contamination is present at the 3005 West Harry Street property at concentrations exceeding its MCL value; however, the soil samples collected during CI did not detect contamination at concentrations exceeding its KDHE RSK soil-to-groundwater pathway. Based on this information, KDHE determined no further response actions by Cessna were necessary.
In March 2021, the Site was referred to the KDHE Site Assessment Program by the KDHE State Cooperative Program to evaluate/determine the source(s) of the detected TCE in groundwater and further evaluate potential indoor pathway of residential properties in the study area.
Based upon the above information, KDHE Site Assessment Program recommends a Site Evaluation be conducted to determine a potential source(s) of TCE groundwater impacts and evaluate potential residential indoor vapor intrusion at the Site. |