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

decomposed in the Decomposition Tank, (forming salt, mercury, and mercuric oxide in solution),
it is then pumped to a filter press for physical separation. See Section 1.2.2 for a description of
the filter press.
After the filter press completes its cycle, the filtrate from the filter press is then pumped into the
Waste Solution Tank (see Section 1.2.2).
23.1.3 Waste Solution Treatment Circuit
Caustic leach waste solution will be treated in the waste solution treatment circuit in the Waste
Solution Settling Tank. The underflow slurry from the Waste Solution Settling Tank containing
mercury precipitants may be periodically pumped to the Decomposition Tank located in the
calomel caustic leach circuit.
The process is designed to allow mercury to precipitate out of the settling tank so it can be
pumped to the Decomposition Tank.
The clarified waste solution from the Waste Solution Settling Tank may be periodically pumped
through activated carbon columns to remove any residual mercury. After this occurs, the
polished waste solution is then sent to the Waste Solution Storage Tank(s) (see Section 1.2.7).
Process waste solution from sources other than the calomel caustic leach circuit may be collected
in the Waste Solution Collection Tank (see Figure 23.1-2).
PMR RCRA Permit Application, Dry Hills Facility Page 121
JBR Environmental Consultants, Inc. | HATCH March 2013