Precious Metals Recovery LLC RCRA Permit Application Dry Hills ...

1.3 Elemental Mercury Storage – 40 CFR 270.14(b)(1)
Elemental mercury will be stored in an enclosed area of the proposed TSF and contained in pigs.
The proposed TSF is designed to store approximately 1,024 pigs of elemental mercury. This is
equivalent to approximately 11 years of received and recovered elemental mercury based on
current production rates (see Section 1.2). Refer to Section 22 for a detailed description of the
container management measures.
This building design includes numerous containment measures which will minimize the release
of mercury in a liquid or vapor state from the proposed TSF to the environment. Measures
include closed pigs themselves; spill trays under the pigs; epoxy coatings on the walls, floor and
ceiling; slab seals; hard washers where racks will be bolted to the floor; maintaining the plant
spaces under negative pressure; appropriate ventilation; and an underlying impermeable
membrane. All containment measures are specified in Section 22.
Pigs will be stacked on spill trays secured to seismically rated racks, as illustrated in Figure 1.3-
1.
Figure 1.3-1: Isometric of Elemental Mercury Storage Rack
The storage racks will have two levels, thereby allowing one tray of pigs to rest on a spill tray on
grade and one to rest on the elevated shelf, also equipped with a spill tray. The spill trays (made
of carbon steel) will be sized to support eight pigs each, arranged two by four, and will have a lip
height sufficient to contain the entire volume of 1 pig in case of leakage. Floors will be graded at
a 1% slope, or more, toward the aisle so that free fluids flow toward the edge of the spill trays.
PMR RCRA Permit Application, Dry Hills Facility Page 37
JBR Environmental Consultants, Inc. | HATCH March 2013