May 2000

Known: One anomaly potentially associated with waste management practices was observed during geophysical survey activities on 7 March 1996, and 2 and 3 April 1996.

Previous Investigations: Three surface soil samples were collected on 8 March 1996 and analyzed by ITS Laboratory for VOCs, SVOCs, and metals. Three soil borings were completed and seven soil samples were collected (two samples from SB1 and SB2, and three samples from SB3) on 26 August 1996. Due to a laboratory error, an additional soil boring was completed next to SB3 to collect an additional SVOC sample from at a depth of 4.5 feet on 15 May 1997. These subsurface soil samples were analyzed by ITS Laboratory for VOCs, SVOCs and metals.

Planned Rework: Replace analytical chemistry data generated by ITS Laboratory. To accomplish this, recollect three surface soil samples from the approximate locations of the first surface soil samples. In addition, complete three additional soil borings in the approximate locations of the first set of soil borings, and collect two subsurface soil samples from RW-B27-SB1 and RW-B27-SB2, and three subsurface samples from RW-B27-SB3. Analyze samples for VOCs, SVOCs, and metals.

Rationale for Analytical Program: Based on prior usage at the site as a sanitary landfill, chemicals of potential concern include VOCs, SVOCs, metals and explosives. Metals (arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel and zinc) are included due to the metallic nature of the waste. VOCs analysis is included in the analytical program to detect typical contaminants associated with a disposal area. SVOCs are included at this site since waste burning may have occurred. There is no evidence of ammunition at the site therefore, samples will not be analyzed for explosives.

Resampling Activities: The following field activities will be performed to gather data for TNRCC closure submittal of SWMU B-27:

1. 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-27. In particular, the geologist will review the PID readings and recovery volumes obtained from the existing boring.

2. Field locate previous sample locations (collected in 1996).

3. Collect three rework surface grab samples (RW-B27-SS1, RW-B27-SS2, and RW-B27-SS3) in the approximate locations of the first three surface grab samples, collected in 1996. Sample locations are shown in Figure B27-1. These samples will be analyzed for VOCs, SVOCs, and metals as indicated in the following table. QA/QC samples will be collected as described in Section 2.4 of the FSP.

4. Complete three soil borings in the approximate locations of the first set of soil borings, completed in 1996 and 1997. Sample locations are shown in Figure B27-1. The rework soil samples will be collected from each boring from the same depth intervals as the first set of subsurface soil samples, 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 = 12 feet, SB2 = 10.5 feet, and SB3 = 13 feet). Each rework sample will be analyzed for VOCs, SVOCs, 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.

5. 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.

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

7. Handle IDW as specified in the FSP.

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

9. 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.