Patent ID: 7111847

Claim:
An additive for stabilizing and passivating a projectile trapping medium and spent projectiles trapped therein, said additive comprising a buffering compound formed as a low density, self-dispensing, foamed concrete block, said low density, self-dispensing, foamed concrete block comprising: one or more dry components selected from the group consisting of low solubility phosphate compounds, low solubility aluminum compounds, iron compounds, sulfate compounds, and calcium carbonate; a cementing material; water; and a quantity of aqueous based foam sufficient to yield a density of said block sufficiently high to prevent said block from being buoyant and sufficiently low to prevent said block from sinking in the projectile trapping medium; wherein said one or more dry components, said cementing material, and said water are provided in substantially stoichiometric amounts according to a formula comprising: about 1 part by mass low solubility phosphate compound; about 1 part by mass cementing material; and about 0.4 parts by mass water.