The Hinds County Wood Preserving Company, Inc. (HCWP) began operations in the early 1960s and ceased operations around 1978. HCWP treated lumber with creosote in two pressure vessels. Remaining on-site as of 11/06/2006 were both pressure vessels (Tanks 2 and 6), three above-ground storage tanks (AST) (Tanks 1, 3, and 5), the facility boiler (Tank 4), and various pieces of equipment and treated lumber. The removal assessment determined 1) that each of the three ASTs contains some amount of material with a collective total of approximately 14,000 gallons, 2) each of the pressure vessels contains some amount of residual creosoting material and one was actively leaking, 3) seven drums of waste oil-water mixture were left on-site, 4) the boiler unit insulation contained asbestos while the pressure vessel’s insulation did not, and 5) equipment contaminated with creosote remained on-site.
The site is drained by several ditches that converge at the northeast, adjacent to Learned Oakley Road, and flow via culverts into Bitter Creek on the east side of the road. The nearest residence is located 120 yards and uphill from the site. The resident maintains a groundwater well on the property, but the house has been connected to a municipal water supply.
Rainwater from storms during the temporary demobilization over the holidays has collected on-site in the contaminated area. No sheen was found on the pool. A subcontractor was hired to pump the pool into a tanker, and a local WWTP agreed to allow the water to be discharged directly into its system. The WWTP has a capacity of 10 MGD, although it usually operates at 5 MGD; the water from the pool was sampled and analyzed by the WWTP prior to discharge. Approximately 22,000 gallons of pooled water was introduced during peak hours over two days to maximize dilution.
Concrete from the site is being disposed of to a C&D landfill.
Metal continues to be decontaminated and sent off-site for recycling.
Results from the soil delineation sampling event were received. Sample locations were marked with the depths at which contamination was or was not found and a footprint for the excavation was established with depths at varying levels. The levels for existing contamination were established using MSDEQ Tier 1 TRG’s for unrestricted (Residential) soils.
Excavation continued by mid week. Creosote contamination could be identified visually in the subsurface soil with staining, layering, and veining. The stained soils were removed and stockpiled. Stained soils could be found at varying depths from 2 feet in some areas to beyond 4 feet in other areas. Near the North edge of the pit, a buried pipe surrounded by wooden cross-ties and filled with creosote-contaminated wastewater was discovered at approximately 2 feet deep. A layer of creosote contamination could be seen veining on both sides of the pipeline. Beneath the layer appeared to be clean native red clay; while above the layer was a non-native cover of clay and gravel mixture.
Heavy rains predicted for the weekend caused a delay in excavation operations. All of the exposed contaminated zones were either removed or covered. Other pits were scraped clean and filled in to prevent ponding. A water diversion system was constructed inside the pit to prevent ponding in contaminated areas and pool the water in a relatively clean zone of the pit.
- Clearing of vegetation and trees to gain access to contaminated areas. (COMPLETE)
- Removal and bulking of contaminated wastes and/or hazardous substances from tanks and drums. (ONGOING)
- Demolition and removal of tanks and removal contaminated materials such as abandoned equipment. (ONGOING)
- Excavate, stockpile and re-locate the contaminated surface soil. (ONGOING)
- Collect and analyze confirmation samples from the excavated areas. (ONGOING)
- Restore and backfill excavated areas with clean fill.
- Conduct additional sampling for waste profiling. (ONGOING)
- Additional sampling to confirm extent and boundary of migrated contaminants. (ONGOING)
- Complete excavation
- Complete deconstruction of Tank 6
- Design treatment system for washwater in frac-tank
Rain will continue to be a problem during the excavation. The pit cannot be allowed to sit open for longer than 1 week.
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