| Contents Notes |
I Introduction -- II Summary and conclusions -- III Recommendations -- Compliance status -- Company approach -- Planned modifications -- Maintenance and operation -- Charging emissions controls -- Process modifications -- Cost estimates -- IV Process description -- Lead smelter -- Zinc fuming plant -- V Applicable regulations -- Regulation F - control of fugitive dust -- Regulation H - control of particulate emissions from industrial processes -- VI Particulate collection and control -- Operation and maintenance -- Process modifications -- Charging emissions collection -- Charging emissions control -- VII Cost analysis -- VIII Related industry experience -- ASARCO - Montana -- ASARCO - Texas -- References -- Bibliography -- Appendices -- A 113 notice of violation -- B Idaho air regulations F and H -- C Calculations The Bunker Hill Company, a subsidiary of Gulf Resources and Chemical Corporation, operates a mine flotation mill, a lead smelter and a zinc smelter at Kellogg, Idaho. Lead and zinc concentrates produced from the mill and from other foreign and United States mills are charged to the custom lead and zinc smelters for processing. Besides refined lead and zinc, the Company produces black and clear sulfuric acid, high-purity silver, antimonial (hard) lead, zinc oxide, dore metal (silver-gold alloy), copper matte and cadmium sponge at this location. On or about September 22, 1976, the Bunker Hill Company was issued a Section 113 (Clean Air Act) Notice of Violation [see Appendix A] addressing several areas of the lead smelter, including the blast furnace, sintering process area, zinc fuming plant, silver retort and lead refinery. Since then, the Company has proceeded with corrective action on all areas with the exception of the zinc fuming plant charge area for which the Company was to provide adequate exhaust capability to an appropriate control device. The Company has refused to comply with control requirements for the zinc fuming furnace charging emissions, stating that these emissions were to insignificant to warrant the cost involved, estimated by the Company to be $300,000. As a result, Environmental Protection Agency (EPA) Region X asked the National Enforcement Investigations Center (NEIC) to analyze the availability and feasibility of technology for the Bunker Hill zinc fuming plant to comply with the fugitive emission regulation (Idaho Air Pollution Regulation F) and the process weight regulation (Idaho Air Pollution Regulation H). Region X also asked the NEIC to determine the capital and operating costs associated with any recommendations. In August 1976, the NEIC inspected the Bunker Hill lead smelter and requested further information from the Bunker Hill Company. The information was provided by the Company during October 1976 with subsequent data requested and provided in January and February 1977. An additional visit to the smelter was made during February 1977. To obtain further background information, the NEIC conducted inspections of the zinc fuming furnace operations at ASARCO lead smelters in East Helena, Montana and El Paso, Texas in 1976-77. |
