2011-12-15_REVISION - M1977493 (2)

Home Browse Search

Technical Revision (TR -18) Climax Molybdenum Company Environmental Protection Plan Permit No. M- 1977 -493 inside the Nokes building. In the new mill, Nokes is planned to be stored in the Reagent Area of the Mill Building. Phosphorous pentasulfide is a reactive and ignitable greenish - yellow solid with a "rotten egg" smell which can affect the human body through inhalation, ingestion, and dermal contact. While solid phosphorous pentasulfide can cause dermal irritation, the primary health hazard associated with this material is the release of hydrogen sulfide gas upon contact with water. Hydrogen sulfide can be a primary health hazard which acts as an irritant to mucus membranes and can produce severe breathing difficulties. High concentrations can stop breathing immediately. Phosphorous pentasulfide, if released to the environment where it contacts water, will react by producing hydrogen sulfide gas and phosphoric acid. Both of these by- products can be injurious to aquatic and terrestrial biota. Phosphorous pentasulfide can be neutralized with an alkaline substance such as lime, NaOH, or soda ash. The use of liquid pre -mixed Nokes will significantly reduce the risk of H generation since the potential for gas generation is greatest during the mix phase. Nevertheless, H monitoring is provided at two locations. One is the truck unloading point where the solution is transferred from a bulk tanker to our storage system. The other is in the liquid Nokes storage tank area. Both monitors are located at low points to quickly detect any H that might be generated. Anticipated usage rates are 0.30 to 0.40 lb of Nokes solution per ton of ore processed. The Nokes will be stored in one tank with a capacity of 18,000 gallons. The Nokes will be stored in the reagent storage area of the mill building (see Mill Building Detail - Area 450 on the south side of the mill building on Figure AM- 06- T -06). Secondary containment with a volume greater than that of the tank will be provided in the reagent storage area (see Reagent Storage Area Detail Figure AM- 06- T -07). Tank level indication will be available locally as well as through the control system. The control system will alarm for a given tank low and high level. A local alarm hom will sound for a given tank high level. In the event of a storage tank failure, the Nokes will be contained in the reagent storage area via secondary containment. The secondary containment area is equipped with a sump but no sump pump. In the event of a release in this area, a pump will be placed in the secondary containment sump and the Nokes will be routed back into the process circuit or pumped into a suitable container for proper disposal through direction from the environmental department. A spill that occurs during offloading into the storage tank will be handled similarly using a sump located in the offloading area. In the event of a Nokes distribution system failure, the Nokes will be contained within the mill building and will be sent to tailings or the rougher concentrate thickener depending on where the failure occurs. T -3.3 Water Treatment Chemicals Information T -3.3.1 Flocculent GreatFloc 5500 is used as a flocculant to facilitate nucleation and settling of hydroxide precipitates. GreatFloc 5500 is a non - hazardous, common commercial flocculant used in the SDP. GreatFloc is an acrylamide polymer that may irritate the skin or eyes. Impermeable gloves and chemical splash goggles should be utilized when working with the chemical to prevent exposure. If the product is released to the environment, it should be contained with absorbent and removed. T - 3.3.2 Lime (Calcium Oxide) Calcium Oxide (CaO), also known as lime or quicklime, is used in the water treatment circuit at Climax to raise the pH and lower metal levels through precipitation. Lime also is used in reclamation operations and at the mill to adjust the pH of process water. Lime is stored at the Lime Station and in small stockpiles associated with current reclamation. Lime is a common, but strong caustic alkali. In high EPP: Version R2 T -12 December 2011