Laboratory tests conducted on several fine-grained industrial barite samples indicate that mercury (Hg) and other trace metals are not released in significant quantities into seawater or the pore water of marine sediment. Mercury, cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) are the primary metals of marine environmental concern in barite because these metals can be enriched by more than an order of magnitude compared to marine sediment. In addition, the USEPA water quality criteria for these metals are relatively low.