SWMU 60 – Old Photographic Laboratory
Proposed Remedial Measure
The proposed remedy for SWMU 60 is excavation and off-site disposal for surface and subfloor soils and debris materials. Excavation and removal of soil off-site to an appropriate landfill or treatment facility was completed as an Interim Corrective Measure (ICM). All contaminants of concern (COCs) that may impact human health, or the environment were removed as indicated by post-confirmation sampling.
There were three monitoring wells installed at SWMU 60; only one provided enough groundwater for a complete sample collection. Groundwater samples were collected for fixed-base analysis of ammonia, nitrate, nitrate/nitrite, RCRA metals (arsenic, barium, cadmium, chromium, lead, mercury, silver, and selenium) plus iron, and SVOCs (Tetra Tech, 2021). All detected analytes were below groundwater TMCLs. Site-specific groundwater will be considered clean closed.
In 2003, the U.S. Army Center for Health Promotion and Preventive Medicine (CHPPM) requested a Relative Risk Site Evaluation (RRSE) be performed at SWMU 60 (Tetra Tech, 2021). During the RRSE, Battelle collected two surface soil samples that were analyzed for SVOCs, volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), and RCRA metals. Twenty-eight different analytes were detected in these two samples (Battelle, 2003). Of the twenty SVOCs detected in soil, benzo(a)pyrene, dibenz(a,h)anthracene, and benzo(a)anthracene exceeded the Target Media Cleanup Levels (TMCLs). The contaminants acenapthylene, benzo(g,h,i)perylene, and phenanthrene were also detected, but no TMCL values are available for comparison. The source of SVOC contamination in the soil sample collected near the southeast corner of Building 214 could not be verified from available historic information. RCRA metals that were detected did not exceed corresponding TMCLs (Battelle, 2003).
In 2005, as part of the Investigation Report and Corrective Measure Work Plan for SWMUs 60 and 61 (Shaw, 2005), subfloor soil samples were collected from beneath the Old Photographic Laboratory’s Dark Room which is in the basement below the west half of the east wing of Building 214. Subfloor soil samples were analyzed for Target Analyte List (TAL) metals, SVOCs, and VOCs. Arsenic concentrations in subfloor soils were above the TMCL (12.6 mg/kg) for surface soil (Shaw, 2005). Vanadium exceeded its TMCL (41.0 mg/kg) in one surface soil at sample location (Shaw, 2005). These results prompted a corrective measure for the contaminated subfloor soil. Exterior soil samples were analyzed for TAL metals and SVOCs; and the ammonia tank area (214-Ammonia Area) was analyzed for ammonia (as N). No contaminant exceeded its TMCL in the exterior soil samples (Shaw, 2005). Following excavation of contaminated soil, confirmation samples indicated that the remaining soils beneath the basement floor were below the TMCL for arsenic.
An RFI was performed at SWMU 60 by Tetra Tech from July 9, 2008 to January 18, 2010 as presented in the RCRA Investigation Report for Soil and Groundwater – Solid Waste Management Unit 60, Old Photographic Laboratory (RFI Report). Five surface soil samples were collected from the outside walls of the east wing of Building 214 for the analysis of RCRA 8 metals plus iron, SVOCs, nitrite/nitrate, ammonia, and chlorinated pesticides (Tetra Tech, 2021). Three surface soil samples were from the east and west sides of the ammonia tank building for the analysis of RCRA 8 metals plus iron, SVOCs, nitrite/nitrate, ammonia, and chlorinated pesticides (Tetra Tech, 2021). Four surface soil samples were collected from the drainage ditch originating from the southeast corner of Building 214 for the analysis of RCRA metals plus iron, SVOCs, nitrite/nitrate, ammonia, and chlorinated pesticides (Tetra Tech, 2021). Groundwater samples were collected from monitoring wells installed at locations downgradient of Building 214 for the analysis of RCRA 8 metals plus iron, ammonia, SVOCs, and nitrate/nitrite (Tetra Tech, 2021).
Soil and groundwater data collected during the RFI and historical soil data was used to identify contaminants of potential concern (COPCs) for SWMU 60 in the RFI Report. COPCs are constituents identified in soil or groundwater samples at concentrations above their TMCLs. Soil COPCs for SWMU 60 included arsenic, vanadium, benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)anthracene, as these contaminants were detected above their respective TMCL in soil samples collected during the RRSE (Tetra Tech, 2021). TMCLs presented in the RFI Report were composed of background conditions for arsenic and 2010 KDHE Risk Based Standards for Kansas (RSKs) for vanadium, benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)anthracene. No COPCs were identified for groundwater. In evaluating the fate and transport of COPCs, it was determined that none of the COPCs identified for soil were detected in groundwater samples collected during the RFI (Tetra Tech, 2021).
On behalf of the Army, Tetra Tech conducted a streamlined health risk evaluation by comparing RFI data to the approved TMCLs for the site. The TMCLs specified for this RFI were primarily risk-based concentrations specified for residential land use (Tetra Tech, 2021).
The RFI identified arsenic, vanadium, benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)anthracene as COPCs at SWMU 60 as these contaminants were detected above their respective TMCL in soil samples collected during the RRSE. However, none of the COPCs were identified as COCs for the following reasons:
- Soils associated with TMCL exceedances of arsenic and vanadium were removed from SWMU 60 during the corrective action performed in 2005.
- Benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)anthracene were identified above their respective 2010 KDHE RSK values at one historic sample location. Five subsequent surface soil samples were collected within the drainage ditch near the historic sample as part of the RFI. Benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)anthracene were not detected at concentrations above their respective KDHE RSKs during the RFI (Tetra Tech, 2021). As a result, the historic exceedances were considered an isolated occurrence, and therefore these constituents were not considered COCs (Tetra Tech, 2021).
Cleanup goals were developed for residents and non-residents, according to the appropriate land-use designation, exposure frequency, and exposure duration. According to the Conceptual Land Use Plan, SWMU 60 falls within the approximately 1,441-acre zone proposed for the business center consisting of mixed offices, research and development, and technology. The business center will be located near the north of the development (Johnson County, 1998). Based on this land use, the potential current and future receptors include:
- Current Construction/Excavation Workers, current,
- Employees as well as adults and children who could frequent the area, future.
The assessment determined that site risks were within acceptable limits. The excavation of surface/subfloor soil and debris removed soils associated with TMCL exceedances. No identified COPCs were selected as COCs for environmental media at SWMU 60. Therefore, there are no COCs identified for soil or groundwater at SWMU 60. Additional evaluation of groundwater in the area will occur when work on GWOU-#4 is done.
- SWMU 60 Statement of Basis, March 2022 (PDF)
- RCRA Facility Investigation Report for Soil AND Groundwater, February 2021 (PDF)
- RCRA Facility Investigation Work Plan, May 2008 (PDF)
- Corrective Measures Work Plan, April 2005 (PDF)
- Risk-based Standards for Kansas (RSK) Manual - 6th Version, July 2021 (PDF)
- Conceptual Land Use Plan Sunflower Army Ammunition Plant (PDF)