Containment—Underground Systems

Lasagna can be installed at many sites with diverse conditions and surrounding environments. The system works well in saturated or vadose zones. Installations have been installed and operated safely in semirural and urban settings. With the process being contained underground, the only pieces of equipment required are the rectifier and a remote data monitoring system. The only structure required is a... 

The demand for gas is highly seasonal. Thus pipeline companies economi2e by si2ing production faciUties to accommodate less than the system s maximum wintertime demand. Underground storage faciUties are used to meet seasonal and daily demand peaks. In North America, gas is stored in three main types of underground formations depleted oil or gas fields, aquifers that originally contained water, and caverns formed by salt domes or mines. 

Tanks and Appurtenances Used to Contain Hazard Substances Including Aboveground Tanks, Underground Tanks, Piping and Appurtenances, and Storm Water Management Systems Associated witb Containment Systems... 

A few years later carbon dioxide was injected into an underground tank containing Jet fuel as a tryout of a fire-fighting system. The tank blew up, killing 18 people who were standing on top of the tank. In this case the discharge may have occurred from the cloud of carbon dioxide particles. 

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. 

Drainage out of process structure/area into an external containment area. The drainage may be achieved either by surface swales or berms, ditches or trenches, or via an underground piping system... 

Tanks installed after the effective date (October 15,1983) of a new Massachusetts law regarding underground storage tanks must have secondary containment and a monitoring system or be constructed of a corrosion-resistant material and... 

The efficiency of the system is dependent on the soil type, contaminant type, and contaminant concentrations. Many sites require that an impermeable barrier or containment wall be constructed to prevent the continued migration of pollutants through soil and water. The treatment area must be clear of underground obstructions. Treatment is generally limited to soil less than 40 ft deep. More energy may be required to achieve contaminant removal in saturated soils. 

Most fuel system storage tanks, transfer lines, and underground pipelines are composed of 1018/1020 carbon steel. These system components are all susceptible to internal corrosion whenever fuel containing water is introduced. Other factors which can enhance fuel storage and transportation system corrosion include ... 

In emergency situations, where a mine ventilation system is compromised and underground fires are releasing dangerous quantities of CO into the mine atmosphere, chemical oxidation of the CO to less-harmful C02 is the usual practice. This is achieved using a self-rescuer apparatus, which is essentially a mask, into which the mine atmosphere is drawn by the respiration of the wearer. As mine atmosphere enters the self rescuer it passes over a CuMn204 catalyst (known as Hopcalite see Veprek el al. 1986), which expedites the oxidation of CO to C02. Normally, self-rescuers contain sufficient Hopcalite to allow for 60 to 90 minutes of use, which will generally be sufficient time to allow the wearer to escape from the mine, or at least to reach a secure fresh air base where the ventilation system continues to operate. 

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