2017-06-02_REVISION - M1980244 (2)

Home Browse Search

CC&V Response: Prior to the operation of the retort, CC&V will place a specially designed spill kit in the refinery to address mercury spills. The spill kit will contain HGX powder; HGX powder is a specially designed product used in the spill clean-up of elemental mercury. A copy of a similar HGX product's SDS has been included in this response for DRMS to review (attachment 1). Composition of the HGX products varies slightly, once CC&V has ordered a HGX product from a manufacture, CC&V will provide DRMS with a copy of the SDS. D. Hazard Mitigation: There are four levels of hazard mitigation and control. The following lists these types of control in order of decreasing effectiveness: Elimination/Substitution; Engineering Controls: Administrative & Work Practice Controls; and Personal Protective Equipment (PPE). Specific comments below refer to these levels of hazard mitigation. Comments Specific to the Submittal. E. Third page, third paragraph — This discussion simply states "Elemental mercury will be transferred from the collector into a one ton flask". During the May I meeting, it was explained to the Division by mine personnel that this transfer would happen by opening a spigot to drain elemental Hg into an open bucket and having a worker carry the bucket across the room to the one ton flask, where it would be "carefully"poured into the flask. This open transfer method is the least effective way to prevent personnel exposure to elemental Hg, allows Hg vapor into the building during transfer, and cannot prevent contamination to the floor of the room if a spill occurs. The MSHA document identified in Comment B states it is common preferred practice that concrete floors be "treated with a non-slip epoxy paint" to prevent contamination of the concrete, in the event of a spill. Contaminated concrete would require disposal in a hazardous waste landfill upon demolition of the building. The Division requires an engineering control method be used to transfer the Hg to the flask (i.e., closed system). If this is impossible, it must be demonstrated as such and an administrative/work practice control must be presented and approved by the Division. Relying strictly on PPE is unacceptable. The Division contacted MSHA to discuss Hg monitoring in the room proposed for the retort. They indicated this room may require either more frequent or continuous monitoring, depending on the frequency and amount of elemental Hg exposed to the indoor environment during an "open" transfer. CC&V Response: CC&V has investigated several options to transfer elemental mercury from the collector to the flask. There are several factors that limit the ability to implement effective engineering controls. The process of transferring mercury to the flask is done on an as needed base, which could be every week, to every few months. The flask cannot be placed underneath the collector because it will not fit. Also the flask can only be moved by a forklift, maneuvering a forklift that close to the collector and retort poses too great of a risk of damaging the equipment. Piping or tubing, would be effective if there were a greater volume of mercury and a constant stream; however this is not the case. Based on estimated mercury production rates, the volume of mercury collected is so low that there is no practical plumbing solution. The system will not yield enough volume of mercury to be able to effectively pump mercury to the flask. Furthermore, in theory more mercury residue would be left in the engineering controls such as piping, than what would be transferred to the flask. Currently no engineering controls exist to separate the water from the mercury. The best method for decanting the water from the mercury is done by visual observation from a trained operator. CC&V will utilize best available practices, procedures, and personnel protective equipment to remove water and mercury from the collector and decant the 2