[Home]
[RFI Report ] [Next Section]
SWMU B-22 RCRA Facility Investigation/Closure Report
Section 2 - Field Investigation
As outlined in the Environmental Encyclopedia site-specific work plan (Volume 1-2, SWMU B-22), the objectives of the site assessment were to collect five surface soil samples at SWMU B-22, with the goal of closing the site under RRS1, if appropriate. All samples were collected in accordance with the Field Sampling and Analysis Plan (Volume 1-4, Field Sampling Plan).
During February 1996, the RL17 Work Plan was submitted to CSSA. Subsequent field activities included a site boundary survey and collection of five surface soil samples, both occurring during March 1996. The samples collected as part of this work under RL17 were analyzed by ITS Laboratories (ITS) in Richardson, Texas. Questionable work from ITS was disclosed in January 1998, and the lab continues to be reviewed by the EPA. In a letter dated April 26, 1999, the EPA determined that any original ITS analyses for any method, and any reprocessed data, do not comply with EPA quality requirements. The EPA concluded that ITS data might be used for evaluation and screening, but ITS data would not be acceptable for clean up or compliance purposes. During November 1999, the Rework Work Plan Addendum was submitted for resampling and replacement of the ITS chemical data.
2.1.1 Geophysical SurveyThe geophysical survey conducted at the site in 1995 is described in Section 1.3. No additional geophysical surveys were conducted during the current investigation at the site.
In accordance with the approved RFI Work Plan, soil gas samples were not collected in association with the investigation for SWMU B-22.
2.1.3 Surface Soil SamplesDuring March 1996, a site boundary survey was performed and five surface soil samples were collected under Delivery Order RL17. The surface soil samples were composed of two soil types, Krum Complex and Trinity & Frio soils. Krum Complex soil samples accounted for the three westernmost samples (B22-SS01, B22-SS02, and B22-SS04) within the site area. The remaining two samples (B22-SS02 and B22-SS05) were Trinity & Frio soils. The samples were collected in a grid-like manner (Figure B22-4).
All soil samples collected during 1996 were submitted to ITS Laboratories. During January 1998, it was learned that these sample results were invalid and cannot be accepted by the EPA. In November 1999, Rework Work Plan Addendum was submitted to recollect samples and replace ITS results. On March 17, 2000, five surface soil samples were recollected at the same approximate locations as the original sample locations. The results section of this report only includes data from the rework sampling event.
Samples collected at SWMU B-22 as part of the rework were submitted to three laboratories. VOC samples were analyzed by Agriculture and Priority Pollutants Laboratories, Inc. (APPL) using EPA method SW-8260B, explosives samples were analyzed by DataChem Laboratories, Inc. using method SW-8330, and metals samples were analyzed by O’Brien & Gere Laboratories, Inc. (OBG). Metal analyses included barium, chromium, copper, nickel, and zinc (SW-6010B); arsenic (SW-7060A); cadmium (SW-7131A); lead (SW-7421); and mercury (SW-7471A). A total of ten environmental samples, two field duplicate samples, one matrix spike sample, and one matrix spike duplicate sample were submitted for analyses.
All sampling points were surveyed by Parsons using a Trimble Asset-grade Global Positioning System (GPS). Surveying methodology is described in the Amendment to the Field Sampling Plan (Parsons ES, 2001b). All sample location and analytical data will be incorporated into the CSSA GIS.
In accordance with the approved RFI Work Plan, subsurface soil samples were not collected in association with the investigation for SWMU B-22.
In accordance with the approved RFI Work Plan, groundwater samples were not collected in association with the investigation for SWMU B-22.
A geophysical survey was not performed at the site during the current RFI. As described in Section 1.3, no anomalies were identified during the geophysical survey conducted at SWMU B-22 in 1995.
In accordance with the approved RFI Work Plan, soil gas survey samples were not collected in association with the investigation for SWMU B-22.
As described in Section 2.1.3, five surface soil samples (RW-B22-SS01 through RW-B22-SS05) and one duplicate sample were collected and analyzed for VOCs, metals, and explosives. Results are summarized in Table B22-1, and a complete list of analytical results is provided in Appendix A. Table B22-1 only lists compounds which were detected in at least one site sample; therefore, explosive-related and other compounds which were not detected in any site samples are not listed on the table.
Methylene chloride exceeded laboratory reporting limits at one sampling location. RW-B22-SS05 and its duplicate sample had reported concentrations of 0.0084 mg/kg and 0.0117 mg/kg (M-flagged value) methylene chloride. The reporting limit for methylene chloride in this sample was 0.005 mg/kg.
Although F-flagged, benzene and toluene were identified in four of the soil samples. All detected values of benzene and toluene were below their respective reporting limits.
In accordance with the approved RFI Work Plan, no subsurface soil samples were obtained during the investigation conducted for SWMU B-22.
In accordance with the approved RFI Work Plan, no groundwater samples were obtained during the investigation of SWMU B-22.