5.0 SAMPLING ACTIVITIES

5.1 Post-Excavation Grid Sampling

Most post-excavation grid sampling was specified in the SOW to be performed using the 50-ft. by 50-ft. grid system previously established for delineation and excavation. Sample collection, quality assurance testing and data interpretation methods were the same as those used during the pre-excavation perimeter delineation sampling program, as reported in Appendix A of the LL WP.

In general, the post-excavation sampling of each 50 ft. by 50 ft. grid consisted of the collection of four samples from the centers of four 25 ft. by 25 ft. subgrids. The four samples were composited and then analyzed, or each sample was analyzed individually by EPA method of 8082.

Verification samples were collected at a O to 6 in. depth intervals. If the analytical result for the composite from the initial depth interval was greater than the clean criteria for that grid, the grid was re-excavated and the verification sampling was repeated. In many cases each of the four samples from that depth interval would be analyzed individually in an attempt to identify the specific location that required re-excavation. In a few cases this approach was used on subgrids as small as 12.5 ft. by 12.5 ft. (1/16th of a full 50 x 50 grid). The sampling protocol was applied until the contamination had been isolated to one or two subgrids. All grid or subgrids were thereby sampled, tested, excavated and re-sampled until the clean criteria for that area was met.

In some cases further excavation or sampling was impractical due to the removal of material down to bedrock. In these cases the government oversite parties were consulted and no further excavation was attempted. No verification sampling was performed in bedrock excavations since no appreciable material remained to sample. Tables 1 and 2, and Figure 4 show grids or subgrids that were excavated to bedrock as BR. All bedrock excavations were backhiled with at least 6 inches of clean compacted clay.

In the southwest part of Area 24, where borings were performed to further delineate FGH/16-17 grids, pre-excavation boring results were used as the verification result. These boring sample results and the agreement made to use these results for verification samples are discussed in Appendix A.

Sidewall sampling was performed on the northern sidewall of the hot spot excavation contours, east of the 31011 ODE line. Sidewall sampling was performed on each 25 ft length of sidewall per the LL WP SAP. To expedite the sidewall excavation, borings were drilled and sampled to find the extent of the PCB contamination requiring excavation. Borings were drilled on a ten foot spacing extending north from the sidewall excavation for each 25 foot subgrid. The waste contained in the boring down to a four foot depth from the surface was composited into a sample and analyzed. The sidewall was excavated back to the hrst boring sample that met the clean up requirement and past the visual standard.

The clean criteria for post-excavation grid sampling varied based on location on the site. All areas had a maximum PCB level for an individual grid as well as a maximum level for the arithmetic average for all grids within an area. Allowable area averages were increased by providing ten inches of clean cover over the grids. Table 1 of Appendix A of the LL WP lists the clean up criteria for various areas of the LL site.

The clean criteria for all areas within the hot spot excavation contours, including the northern sidewall hot spot excavation contours, east of the 31011 00E line, was '100 ppm for individual grids with an average for the areas not to exceed 50 ppm.

Areas outside of the LOC had various clean up criteria based on future access to the area (inside or outside the fence) and whether the area was considered residential or not. Areas outside of the security fence, except on the south perimeter, were required to have a maximum individual grid sample result at less than 5 ppm with an arithmetic average for all grids in the area at less than 5 ppm if ten inches of cover were used or at 2 ppm if no cover was used. Areas inside the security fence and outside of the LOC, except on the south perimeter, were to be cleaned up to a maximum of 20 ppm for an individual grid with an area average of less than 10 ppm with ten inches of cover.

The south perimeter outside of the LOC had a less stringent standard. Individual grids were cleaned up to less than 35 ppm. The average of all grids in these areas is to be less than 20 ppm. Individual grids that were more than 5 ppm in which the soils are accessible to people were covered with 10 inches of clean soil cover.

Table 1 of the LL WP summarizes the cleanup criteria, grid size and cover requirements for each of the areas that required excavation and verification sampling under this project. Figure 5 shows the locations of these areas within the site plan. All final post-excavation grid sampling results are shown by grid or subgrid on Figure 4 and also presented by area in Table 1. The arithmetic average for each area is also listed in Table 1.

5.2 Personnel Monitoring

Personnel exposures were evaluated by using personnel sampling pumps in accordance with NIOSH Method 5503 for PCBs, NIOSH Method 1501 for benzene, toluene, ethylbenzene, and xylenes, NIOSH Method 7400 for asbestos, and NIOSH Method 7300 for lead. These methods use small, portable air sampling pumps that are worn by workers. Polychlorinated biphenyl samples are collected on a Florisil- containing sampling medium preceded in line by a glass fiber filter. Both the Florisil tube and the filter are submitted for laboratory analysis. Samples for VOC analysis are collected in a solid sorbent (charcoal) tube. Samples for asbestos and lead analysis are collected on a cellulose ester membrane filter. To quantify worker exposures, the samples are collected in the personal breathing zone of workers for a duration of at least 7 hours.

Exposure monitoring was performed on site personnel working in excavation areas. These activities included capacitor removal, capacitor loading, grid excavation, waste excavation, and consolidation. Table 7 summarizes the samples and results collected from the site. Samples were collected for various constituents at the discretion of the health and safety coordinator, based upon work activities and corresponding hazard.

The health and safety officers on site monitored site operation procedures and the resulting personnel monitoring sample results, especially in the capacitor handling operations. Changes were implemented to worker operations as needed to keep the exposure levels low.

The results of all personnel monitoring at the site show that all personnel exposures to PCBs, asbestos, lead, benzene, toluene, xylenes and ethylbenzene during site activities were below the designated action levels, TLV's, and PEL's.

5.3 Perimeter Air Monitoring

Perimeter air sampling was performed to ensure that excavation and material handling operations did not result in excessive airborne PCB emissions from the site. Air samples were collected using modified polyurethane foam (PUF) samplers in accordance with USEPA Method T-04 and the site-specific Air Monitoring Plan (AMP) dated, April 28, 2000. Air samples were analyzed to determine the concentrations of PCBs at the boundaries of the LL Landfill site during excavation operations. Perimeter air monitoring was conducted by PSARA.

Air monitoring stations were originally located at five locations, north, west, south, east and southeast along the perimeters of the site as described in the AMP. Figure 5 shows the PUF sampler locations throughout the project. Sampling was to be conducted only on days when material handling or excavation took place.

Per the LL WP, background samples were taken at all PUF locations before the start of excavation. Background samples on April 19 and 20 were analyzed. The highest background sample result obtained was from the south sampler on April 19. This sample result was 57.8 ng/m3.

Per the LL WP,one sample representing the prevailing down-wind direction was to be selected each day for analysis at an offsite laboratory. A meteorological station was installed and operated at the site in order to determine prevailing wind direction and weather information. Before the start of excavation at LL, Viacom agreed to analyze the southeast sample (near the Griffin Property) each day along with the sample in the prevailing wind direction. Daily PUF sampling began on May 17 when excavation began as discussed in Section 4.5.1.

In the beginning of June, high PUF results were experienced as discussed in Section 4.5.2. A dust control program, including a clean clay cover over the consolidation pile, resulted in a reduction in air emissions. Starting on June 5, all PUF samplers closest to the neighboring residents were analyzed daily. This included the east, southeast and north PUF samples. If the daily prevailing wind was different than these three directions, it was also analyzed.

After the July shutdown as discussed in Section 4.5.5.1, Viacom agreed to add three new PUF samplers in the residential neighborhood to the north and east of the LL site. On August 8 the Woods, Bender and Gray St PUF samplers were put into service. The locations of these three samplers are shown on Figure 5. The addresses of residents where the three new PUF samplers were installed are:

Up until the July shutdown, sample results were reported two days after the sample was collected. When excavation restarted on August 16, PUF results were obtained for all locations and sample results were expedited so that results were reported the day after the samples were collected.

On August 15, a PUF sampler was located on the Moore property, about 60 feet to the east of the Griffin property. This sampler was installed to take the place of the southeast sampler for use when the Griffin property excavation began. Both the Moore and the southeast sampler were operated and the samples analyzed from August 15 until August 24 for comparison. Therefore, a total of nine PUF samples were analyzed each day during this period.

The Moore sampler was deactivated when it was decided to relocate the southeast sampler to the eastern property line on the Griffin property. The southeast sampler was relocated to the Griffin east fence line on September 1, as shown on Figure 5. This PUF location is referred to as the Griffin location on the air sampling log.

A new south PUF sampler was installed on September 5. The new location was 300 feet south of the old south location, away from the tree line and into the cemetery, as shown on Figure 5. The new PUF location is referred to as the Valhalla sample location on the air sampling log. The sampler at the old south location was operated and the samples analyzed until September 12, along with the new Valhalla sampler for comparison. After September 12 the old south PUF sampler was removed.

At the September 19 weekly meeting the government parties gave approval to return to the 48 hour turnaround of PUF sample results instead of the expedited overnight turnaround. All eight PUF samples for each day were still being analyzed.

On October 1, the Valhalla PUF sampler was relocated approximately 400 feet east and 100 feet north, as shown in Figure 5. This PUF sampler was relocated at the request of the cemetery, as the excavation moved toward the southeast corner of the site. The new PU

On Friday, November 3, the operation of the three neighborhood PUF samplers, Woods, Bender and Gray Street, was discontinued with the approval of the EPA. The remaining five perimeter PUF samples were still analyzed each day. On November 9, the number of PUFs analyzed was further reduced to only the primary wind direction each day and the secondary wind direction when a significant secondary component was recorded.

PUF sampling was discontinued on November 13, when all site operations related to waste handling were completed and all exposed waste surfaces were covered.

The five perimeter PUF samplers were run again to obtain background samples after the project was completed. Samples were analyzed for the north, east, south, west and Griffin sample locations on December 5, 6 and 7. All results obtained during these days were less than 7 ng/m3.

In summary, Viacom collected high volume air samples while the excavation and consolidation of waste was being conducted. Samples were collected and analyzed from May 17, 2000 to November 13, 2000. Additionally background samples were taken prior to excavation on April 19 and April 20, 2000 and also on December 5, 6, and 7 Table 5 presents all the perimeter air sample results obtained for the LL Landfill site.

5.4 Voyager VOC Sampling

The Voyager was typically located at the fence line on the east side of the LL site, which was generally the downwind direction. This location was also the closest to the local residents. Early in the project the unit was moved to monitor other locations, however this was discontinued in favor of monitoring nearest to the local residents. The unit operated on batteries that lasted about 4.5 hours per charge. Typically 8 to 10 low volume air samples were taken daily during the hottest part of the day. The unit was kept in an insulated box containing ice packets to reduce the ambient operating temperature during the extremely hot days. The unit was not run on rainy or extremely damp days.

Sample duration lasted 20 seconds with an analysis time of 20 minutes after which the unit purged for 10 minutes prior to the next low volume sample occurring. No significant levels of VOCs were detected throughout the project and location made no difference in detection. Operation of the Voyager was discontinued on October 18.

5.5 Wastewater Sampling

A wastewater treatment plant was mobilized and constructed at the southwest corner of the site by WRS in accordance with the WP. The system consisted of 250,000 gallon portable influent holding tanks, 250,000 gallon portable effluent holding tanks and associated carbon vessels, pumps and transfer hoses.

A total of 35 batches of storm water runoff were collected and pumped to the influent tanks. These 35 batches represent a total of 865,000 gallons of storm water treated in the wastewater treatment system. The treated water was used for dust control on haul roads and excavations inside the LOO or discharged to Sargent's Pond.

Prior to releasing each batch of treated water, the water was sampled. The sampling consisted of the collection of a 1-liter amber jar of treated water from one of the effluent holding tanks. The sample was shipped under chain-of-custody control to Heritage Environmental Laboratories in Indianapolis, Indiana. Analysis was performed to reveal if the sample was below the .3 ppb PCB limits required by the SOW. Table 10 lists each batch of water that was treated and released or used for dust control.

5.6 Groundwater Monitoring

For quality assurance purposes, duplicate, matrix spike, and field blank samples were collected and analyzed. All samples were labeled, logged onto chain-of- custody forms, stored on ice and transported in insulated coolers to Heritage Laboratories of Indianapolis, Indiana or Antech Laboratory in Export, PA for analysis of PCBs using EPA Method 608/SW-846, Method 8082, and a detection limit of 0.1 parts per billion (ppb). Other field measurements and PCB analytical results for these sampling events are summarized in Table 9.