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Quantity of a regulated substance in an aqueous solution

When using RMP*Comp to conduct an offsite consequence analysis (OCA), a facility must specify the quantity released. What quantity should be entered for a regulated toxic substance in an aqueous solution, the total quantity of the aqueous solution or just the quantity of the toxic substance?

The entire quantity of the aqueous solution should be entered as the quantity released. For example, when using RMP*Comp to analyze a scenario involving 20,000 pounds of a 30% solution of ammonia in water, the chemical should be identified as "ammonia (water solution)," the initial concentration should be identified as 30%, and the quantity released should be specified as 20,000 pounds.