SWMU B-8

Soils: Krum Complex

Known/Previous Investigations (updated): This site was identified during the 1993 environmental assessment (ES, 1993) and confirmed by a geophysical survey of the area in 1995. The site consists of an area approximately 150 ft. long by 150 ft. wide. In 1997 the geophysical anomaly was excavated to identify the buried objects and to confirm that no buried UXO existed. The excavation team found only a broken concrete slab with rebar. There was also metal piping, and a minor amount of small arm projectiles on the surface, which were all gathered and disposed of off-site. The buried debris was located approximately 2 feet bgs. After the concrete slab was removed, the area was swept again to ensue that no other metal debris existed at greater depth.

Planned Rework: Replace previous analytical chemistry data generated by ITS laboratory. To accomplish this, complete three additional borings in the approximate locations of the first set of soil borings, and collect three samples from each soil boring location (surface soil, middle and bottom boring depths). Analyze the samples for VOCs, explosives, and metals.

Rationale for Analytical Program: Based on prior usage at the site as a fired small arms ammunition brass area, chemicals of potential concern include VOCs, metals and explosives. Metals (arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel and zinc) are included due to the metallic nature of the waste. Ammunition may include explosives residue therefore, an analysis for explosives will be conducted. VOCs analysis is included in the analytical program to detect typical contaminants associated with a disposal area. SVOCs are not included at this site since no evidence of waste burning has been found.

Resampling Activities: The following field activities will be performed to gather data for TNRCC closure submittal of SWMU B-8.

The boring logs from the original drilling of SB1, SB2, and SB3 will be copied and reviewed by the supervising geologist prior to beginning any rework at SWMU B-8. In particular, the geologist will review the PID readings and recovery volumes obtained from the existing borings.

Field locate previous sample locations (collected in 1996).

Complete three soil borings in the approximate locations of the 1996 soil borings, as shown in Figure B8-1. Collect samples from the surface and from the same depth intervals as the previous work, unless field instruments indicate that VOCs are present in the boring from a different depth. If PID readings indicate VOCs are present, then the subsurface soil sample from that interval will be submitted to the laboratory for analysis. The total depth of each boring will be at approximately the same depth as the first set of soil borings (SB1= 9.5 feet, SB2 = 12 feet, and
SB3 = 13.9 feet BGL). Each rework sample will be analyzed for VOCs, explosives, and metals as indicated in the following table. Metals include arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, and zinc. QA/QC samples will be collected as described in Section 2.4 of the FSP.

Boring logs for the rework soil borings will not be completed. Instead, the original boring logs created from the boring completed in 1996 will be available onsite during rework activities. Changes to the boring logs will be made if field personnel observe a difference in the rework boring from the original soil boring.

Water is not expected to be encountered in the borings at the site. However, if water is discovered in any of the soil borings it will be reported to AFCEE and CSSA immediately. Completion of wells is beyond the scope of this rework as no monitoring wells were previously installed at this site.

Handle IDW as specified in the FSP.

Analytical results for the data quality rework samples will be reported in the Rework ITIR.

If the results of the above work indicate that the site can be closed under RRS1 without any further investigation and/or remediation, a technical/closure report will be prepared and submitted in accordance with TNRCC closure requirements. If the site does not meet RRS1 closure requirements, a technical report describing the results of the investigation and recommended additional investigation and/or remediation will be prepared under the RL17 SOW.

Historical Analytical Program and Rework Sampling Plan (highlighted in bold)