Disposal sites

Hagerstown 202 hybrid poplar wastewater disposal site, energy use of wood plaimed... 

All processes in a nuclear plant, in a treatment facility, or at a disposal site are governed by rules of the U.S. Nuclear Regulatory Commission (NRC)... 

Radiation dose limits at a disposal site boundary are specified by the NRC as 25 x 10 Sv/yr (25 mrem/yr), a small fraction of the average radiation exposure of a person in the United States of 360 x 10 /Sv/yr (360 mrem/yr). Protection against nuclear radiation is fully described elsewhere... 

Isolation of radioactive wastes for long periods to allow adequate decay is sought by the use of multiple barriers. These include the waste form itself, the primary containers made of resistant materials, overpacks as secondary layers, buffer materials, concrete vaults, and finally the host rock or sod. Barriers limit water access to the waste and minimize contamination of water suppHes. The length of time wastes must remain secure is dependent on the regulatory limit of the maximum radiation exposure of individuals in the vicinity of the disposal site. 

Additional operations essential to commercial bauxite processing are steam and power generation, heat recovery to minimise energy consumption, process liquor evaporation to maintain a water balance, impurity removal from process liquor streams, classification and washing of ttihydrate, lime caustication of sodium carbonate [497-19-8] to sodium hydroxide [1310-73-2] repair and maintenance of equipment, rehabiUtation of mine and residue disposal sites, and quaUty and process control. Each operation in the process can be carried out in a variety of ways depending upon bauxite properties and optimum economic tradeoffs. 

In 1980, Congress deterrnined that each state should be responsible for ensuring the proper handling and disposal of commercial low level nuclear wastes generated in their states. Regional disposal sites have also been estabHshed at BamweU, South Carolina, and Ward Valley, California. These wastes are handled by Hcensed disposal faciHties where they are packaged, placed in burial trenches, and covered with soil. Less than half of the low level nuclear waste produced annually in the United States comes from nuclear power plants. Low level nuclear power plant wastes include contaminated equipment. 

Ocean Disposal. Disposal of raw or treated sludge by barging to sea was practiced for many years by some coastal cities, but today is highly controversial, and it appears that this method will be no longer economically feasible. Federal regulations require that sludge be taken to disposal sites about 160 km from the coast, whereas formerly, disposal sites were permitted within 20 km offshore. Transportation costs are expected to be so high that ocean disposal will be discontinued. 

Because of the wide variability in sludge characteristics and the variation in acceptability of treated sludges for ultimate disposal (this is a function of the location and characteristics of the ultimate disposal site), it is impossible to prescribe any particular sludge-management plan. In the sections below, general performance of individual sludge-treatment processes and operations is presented. 

Transfer and Transport The func tional element of transfer and transport involves two steps (1) the transfer of wastes from the smaller collection vehicle to the larger transport equipment and (2) the subsequent transport of the wastes, usually over long distances, to the disposal site. 

Systems with self-loading compactors. Container size and utilization are not as critical in stationaiy-coutaiuer systems using self-loading collec tion vehicles equipped with a compaction mechanism (see Fig. 25-61 and Table 25-59) as they are in hauled-container systems. Trips to the disposal site, transfer station, or processing station are made after the contents of a number of containers have been col-lec ted and compacted and the collec tion vehicle is fuU. Because a variety of container sizes and types are available, these systems may be used for the coUection of all types of wastes. Container sizes vaiy from relatively small sizes (0.6 m ) to sizes comparable to those handled with a hoist truck (see Table 25-58). 

The hinctional element of tmn.sfer and transport refer.s to the rnean.s, facihtie.s, and appiirtenance.s ii.sed to effect the tran.sfer of wa.ste.s from relatively. small collection vehicles to larger vehicles and to transport them over extended distances to either processing centers or disposal sites. Transfer and transport operations become a necessity when haul distances to available disposal sites or processing centers increase to a point at which direct hauling is no longer economically feasible. 

I. Trailers and sennifrailers. In recent years, because of their simplicity and dependability, open-top trailers and semitrailers hav e found wide acceptance (see Table 25-60). Some trailers are equipped with sumps to collect any liquids that accumulate from the solid vv astes. The sumps are equipped with drains so that they can be emptied at the disposal site. 

Another auxiliaiy unloading system that has proven to be very effective and efficient involves the use of moveable, hydraulically operated truck dumps located at the disposal site. Operationally, the trailer is backed up onto one of the tipping ramps, with or without its tractor. The back of the trailer is opened, and the unit is then tilted upward until the wastes fall out by gravity. The time required for the entire unloading operation typically is about 5 min per trip. 

Water Transport Barges, scows, and special boats have been used in the past to transport sohd wastes to processing locations and to seaside and ocean disposal sites, but ocean disposal is no longer practiced by the United States. Although some self-propelled vessels (such as U.S. Navy garbage scows and other special boats) have been used, most common practice is to use vessels towed by tugs or other special boats. 

Manual Component Separation The manual separation of solid-waste components can be accomplished at the source where solid wastes are generated, at a transfer station, at a centralized processing station, or at the disposal site. Manual sorting at the source of generation is the most positive way to achieve the recoveiy and reuse of materials. The number and types of components salvaged or sorted (e.g., cardboard and high-quality paper, metals, and wood) depend on the location, the opportunities for recycling, and the resale market. There has been an evolution in the solid waste indus-tiy to combine manual and automatic separation techniques to reduce overall costs and produce a cleaner product, especially for recyclable materials. 

Identification of Waste Constituents In any processing (and disposal) scheme, the key item is knowledge of the characteristics of the wastes to be handled. Without this information, effective processing or treatment is impossible. For this reason, the characteristics of the wastes must be known before they are accepted and hauled to a treatment or disposal site. In most states, proper identification of the constituents of the waste is the responsibility of the waste generator. 

Site Selection Factors that must be considered in evaluating potential solid-waste-disposal sites are summarized in Table 25-71. Final selection of a disposal site usually is based on the results of a preliminary site survey, results of engineering design and cost studies, and an environmental-impact assessment. 

Avadahle land area In selecting potential land disposal sites, it is important to ensure that sufficient land area is avadahle. Sufficient area to operate for at least 1 year at a given site is needed to minimize costs. 

Haul distance Although minimum haul distances are desirable, other factors must also he considered. These include collection-route location, types of wastes to he hauled, local traffic patterns, and characteristics of the routes to and from the disposal site (condition of the routes, traffic patterns, and access conditions). 

LandtiUing of Hazardous Wastes In many states, the only disposal option available for most hazardous wastes is landfilling. The basis for the management of hazardous-wastes landfills is set forth in the Resource Conservation and Recovery Act of 1976. In general, disposal sites for hazardous wastes shoiild be separate from sites for municipal solid wastes. If separate sites are not possible, great care must be taken to ensure that separate disposal operations are maintained. 

Site Selection Factors that must be considered in evaluating potential sites for the disposal of hazardous waste are covered in state and federal regulations. In Cahfornia, landfills where hazardous wastes can be received are referred to as Class I disposal sites. To quahfy as a Class I site, it must be shown that ... 

Underlying geological formations that contain rock fractures or fissures of questionable permeabihty must be permanently sealed to provide a competent barrier to the movement of hquids or gases from the disposal site to usable water. 

Sites that comply with the above-noted clauses but would be subject to inundation oy a tide or a flood of greater than lOO-year frequency may be considered by the regional board as hmited Class I disposal sites. 

LEACHATE Liquid that leaks from waste disposal sites. (In a broader sense liquid, e.g. solution, removed from a solid by a solvent, sueh as water.)... 

U.S. EPA. Handbook-Remedial Action at Waste Disposal Sites (Revised). EPA/625/6-85/006. Office of Emergency and Remedial Response, Washington, D.C., 1985. 

Case 2 - The Hyde Park Landfill site, located in an industrial complex in the extreme northwest corner of Niagara, New York, was used from 1953 to 1975 as a disposal site for an estimated 80,000 tons of chemical waste, including chlorinated hydrocarbons. A compacted clay cover was installed in 1978 over the landfill and a tile leachate collection system was installed in 1979. Hazardous compounds such as ortho-, meta- and para-chlorobenzoic acid toluene ortho- and meta-chlorotoluene 3,4-dichlorotoluene and 2,6-dichlorotoluene were detected in the leachate (Irvine et al., 1984). Since 1979, the existing leachate treatment system has used activated carbon as the technology for removing organic carbon. Although... 

Hatch, J. and E. Hayes. "State-of-the-Art Remedial Action Technologies Used for the Sydney Mine Waste Disposal Site Cleanups," In Management of Uncontrolled Hazardous Waste Sites Proceedings, Washington, D.C., 1985, pp. 285. 

Records and prints waste disposal manifests on official forms and outputs reports by waste category, transporter, and disposal site. Also records MSDSs. Requires 256K memory. 

The solids that result from wastewater treatment may contain concentrated levels of contaminants that were originally contained in the wastewater. A great deal of concern must be directed to the proper disposal of these solids to protect environmental considerations. Failure to do this may result in a mere shifting of the original pollutants in the waste stream to the fmal disposal site where they may again become free to contaminate the environment and possibly place the public at risk. A more reasonable approach to ultimate solids disposal is to view the sludge... 

As said previously, records are the property of the organization and not personal property so their destruction should be controlled. The controls should ensure that records are not destroyed without prior authorization and, depending on the medium on which data is recorded and the security classification of the data, you may also need to specify the method of disposal. The management would not be pleased to read details in the national press of the organization s performance, collected from a waste disposal site by a zealous newspaper reporter ... 

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