N Liquid Waste Disposal Facility

Environmental Problems—This section describes N Reactor operational activities that affected the environment. The affected environs are groundwater contamination (radionuclides, volatile organics, polychlorinated biphenyls (PCB), metals, and other Inorganics) soil contamination (surface and vadose zone contamination from radionuclides and organic compounds) biota contamination (flora [vegetation] and fauna [animals] from radionuclide uptake by plants or Ingestion by animals) and evaluated radiation at the Columbia River (unshielded sediments In the 1301-N Liquid Waste Disposal Facility). 

Table 5-2. Selected Radionuclide Inventory for 116-N-l Crib and Trench for the 1301-N Liquid Waste Disposal Facility (WHC 1987b).

WHC, 1987b, Closure/Post Closure Plan 1301-N Liquid Waste Disposal Facility, Westinghouse Hanford Company, Richland, Washington. 

The unsaturated (vadose) zone is contained in Hanford Formation sediments. This zone is approximately 9 m (30 ft) thick. These sediments typically are open-framework pebble- to boulder-sized gravels. Interstitial sand content is generally low and mud-sized sediment is limited to coatings on individual grains and rip-up clasts. Interstratified lenses of sand and mud may be encountered, but they are very localized. Drilling of one well at the 100-N Area near an active liquid waste disposal facility in 1984 led to the only known occurrence of a perched water table within the 100 Areas. 

The 1325-N LWDF, shown in Figure 3-20, started receiving part of the N Reactor liquid radioactive effluent in 1985. In September 1985, the 1325-N LWDF became the primary liquid radioactive waste disposal facility for the N Reactor. The nominal effluent flow rate during reactor operation was 6,345 L/min (1,700 gal/min) and is now less than 7.5 L/min (2 gal/min). 

The 116-N-3 crib was constructed as a replacement liquid radioactive waste disposal facility for the 116-N-l crib and trench and first received N Reactor effluent in 1983. The 116-N-3 trench was put in full service in September 1985 (DOE-RL 1990). Between these two dates, both the 116-N-l and the 116-N-3 facilities were in service. Both the 116-N-3 crib and trench are covered by precast concrete panels to prevent access by the local fauna to contaminated water. 

N Receives spent radioactive internal decontamination solution from the 116-N-2 radioactive chemical waste storage facility and the 107-N basin recirculation facility. Effluent transferred by railway tank cars to 200 Area tank farms for processing and disposal. Liquid waste loadout station. 

N-1 1301-N Liquid radioactive waste disposal system for N Reactor. Effluents from reactor coolant system, spent fuel storage basin, periphery coolant systems, and various radioactiv e drain systems in the reactor facility. Also disposal area for various laboratory chemicals. Historical average high flow rate of 2.100 gal/min. Crib and trench. 

Replace the 1325-N LWOF with a waste water treatment system satisfying best available technology (BAT) requirements by 1995 and treat waste water at the Liquid Effluent Treatment Facility in the 200 Area with subsequent disposal of the treated effluent to a soil column disposal site. Alternatively, this waste water may be treated at N Reactor with discharge of the treated effluent to the Columbia River through an NPDES permitted outfall. 

The 1314-N LWLS is a transfer station consisting of numerous valves, pumps, underground and overhead piping and couplings, and underground tanks at the north end of the 100-N Area, approximately 90 m (300 ft) from the Columbia River. The unit received liquid radioactive waste from the 116-N-2 radioactive chemical waste treatment and storage facility and the 107-N spent fuel basin recirculation facility. The waste was transferred into railway tank cars and transported to the 200 Area for processing and disposal. 

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