Preliminary control technology assessment of Standard Metals Corporation, Silverton, Colorado.
Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, ECTB 111-15A, 1981 Sep; :1-4
A visit was made to the Standard Metals Corporation (SIC-1031), Silverton, Colorado, to evaluate control methods used to prevent worker exposures. The facility was involved in the beneficiation of lead (7439921) ore. Substances used in this process which can be dangerous to workers include lead (7439921), silica (14808607), nuisance dusts and flotation reagents. The mill processed about 1,000 tons of crude ore per day. Mine ore was hauled by truck and dumped in a coarse ore bin. Ore was reduced to less than 3 inches in a jaw crusher and further to minus 3.4 inch in two cone crushers. Ore was stored in a 1000 ton capacity fine ore bin from which it was further comminuted in a rod mill, passed through a spiral classifier into a cyclone feed pump. Underflow passes to a Denver mineral jig which separates the gold with the remainder of the material being dewatered and solids pumped to the tailings pond. Overflow goes to the lead flotation circuit where both lead and copper were floated off as a concentrate. Tailing went through the zinc flotation circuit to yield a zinc concentrate. Calcium- hypochlorate was added to the liquid to destroy the sodium-cyanide before being allowed to overflow into the river. Respirators and other personal protective equipment were used extensively. The author recommends that this company not be included in an in depth study.
NIOSH-Author; NIOSH-Survey; Field-Study; Region-8; Control-methods; Control-technology; Refineries; Metal-refining
7439-92-1; 7439-92-1; 14808-60-7
Field Studies; Control Technology
NTIS Accession No.
National Institute for Occupational Safety and Health