Secondary containers

Diked or Unitized Secondary Containment. Small tanks can have a secondary-containment dam built integrally into the tank. This is essentially within a steel box. These tanks may be either vertically or horizontally oriented in both cylindrical and rectangular shapes. The secondary-containment dikes may be open or closed. Closing the dikes makes access to the primary-containment tank more difficult, but keeps out rainwater. 

Vaulted. Vaulted tanks are installed inside a concrete vault. The vault, itself a Hquid-tight compartment, reduces the fire protection requirements as the NFPA and the International Fire Code Institute (IFCI) recognize these tanks as fire-resistant aboveground storage tanks. The vault provides a two-hour fire wall, thermal protection that minimizes tank breathing losses and pollution, secondary containment, and baUistic protection. 

For normally buried tanks, tanks with measures against buoyancy and tanks with a secondary containment, no difficulties are to be expected for protection current densities below 200 fJ.A m. On the other hand, the protective action can... 

Secondary containment systems are best described as passive protective systems. They do not eliminate or prevent a spill or leak, but they can significantly moderate the impact without the need for any active device. Also, containment systems can be defeated by manual or active design features. For example, a dike may have a drain valve to remove rain water, and the valve could be left open. A door in a containment building could be left open. 

Green zone A compartment of secondary containment used in the atomic energy industry. 

Geomembrane These liners chiefly provide impermeable barriers. They can be characterized as (1) solid waste containment hazardous landfill, landfill capping, and sanitary landfill (2) liquid containment canal, chemical/brine pond, earthen dam, fish farm, river/coastal bank, waste-water, and recreation (3) mining, leach pad and tailing ponds and (4) specialties floating reservoir caps, secondary containment, tunnel, erosion, vapor barrier, and water purification. Plastics used include medium to very low density PE, PVC, and chlorosulfonated PE (CSPE). (The Romans used in their land and road constructions what we call geomembrane.)... 

Are raw process and waste materials stored in a safe and appropriate manner for example, are bulk acids in tanks bunded with secondary containment, are flammable materials in a fire-protected, ventilated store, are powders and pellets in areas fitted with dust extraction segregation of noncompatible materials Provide details of existing storage arrangements, inducing plans and specifications. Identify risk areas. Identify the risk category. 

Transfer facilities, processors and rerefiners, and burners must also have secondary containment systems to prevent oil from reaching the environment in the event of a spill or leak. Secondary containment consists of an oil-impervious dike, berm, or retaining wall to contain releases, as well as an oil-impervious floor to prevent migration. 

In order to regulate USTs storing hazardous substances and to provide a second means of containing the substance should the tank fail, U.S. EPA revised Subtitle J of the RCRA, which regulates secondary containment systems. This secondary containment system would have the following features ... 

Facilities that transfer hazardous waste directly from a transport vehicle (e.g., a tanker truck) to the BIF without first storing the waste must comply with special requirements.5 Generally, direct transfer operations must be managed in a manner similar to that required by the regulations for hazardous waste storage tanks and containers. In addition, the direct transfer equipment must have a secondary containment system, the owner/operator must visually inspect the operation at least once every hour, and the facility must keep records of these inspections. 

An alternate system, one based on gravity, requires penetration of both the FML and clay components of the secondary composite liner system. It also requires a monitoring and collection manhole on the opposite side of the landfill cell. The manhole and connecting pipe, however, become an underground storage tank that needs its own secondary containment and LDSs. 

Lo IMC, Yang X (2001) Use of organoclay as secondary containment for gasoline storgae tanks. J Environ Eng 127 154-161... 

A protocol for the light microscope radioautography of Lilium longiflorum pollen tubes labeled with [14C]-proline follows. This protocol, which does not require tissue embedding in paraffin or Paraplast, can be modified for paraffin-embedded tissues see Chapter 2). Thus, by employment of the protocol, together with the preceding introductory information in this chapter, one should be able to derive a protocol applicable to the cells or tissue in question. The performance of the protocol requires approval of an institution s Radiation Safety Officer. An inventory of incoming radionuclides, their presence in secondary containers, and their waste must be carefully recorded. The waste must be further broken down into solid waste, liquid waste, and animal carcasses to aid in its proper disposal. 

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