The Cinnabar Mine site is a private inholding within the Payette National Forest located 15 miles east of Yellow Pine, Idaho. The mining site encompasses approximately 50 acres. Mercury mining operations began in 1921 and stopped in 1958. The deposit was discovered around 1902 with subsequent development commencing in 1921 under the United Mercury Mines Company (known then as Hermes mine). Production is reported to have been intermittent prior to 1930. In 1942, the mine was taken over by Bonanza Mining, Inc. The major mine development occurred during the 1950s under Holly Minerals. The extraction process employed by Holly Minerals utilized wet floatation and electro-separation. No reclamation has been performed at the site.
Forest Service records indicate the Cinnabar Mine involves mostly privately owned lands acquired through the patent process of the 1872 Mining Law. The private lands are situated in part on lands under the jurisdiction of the USDA Forest Service, Payette National Forest. Pursuant to CERCLA, the U. S. EPA has jurisdiction over patented mining claims located within federal lands.
Contaminants of concern at Cinnabar are primarily mercury, methyl mercury, and arsenic. The objective of EPA's assessment activities is primarily to better understand the fate and transport of mercury coming from residual mining tailings at the site and specifically once contamination reaches Cinnabar Creek, which bisects the site.
The Cinnabar Mine site is located 15 miles east of Yellow Pine, Idaho, on Forest Service Road Number 412 to Road Number 374 (78 Miles from McCall). The Cinnabar Mine site is reached by traveling east from McCall, Idaho, on Forest Service Road Number 48 to the unincorporated town of Yellow Pine, Idaho. The site, which encompasses approximately 50 acres, is located in Township 18 North, Range 10 East, Sections 6 and 7 of Valley County, Idaho. The latitude-longitude coordinates are 44 degrees 55 minutes 13.6 seconds North, 115 degrees 17 minutes 18.7 seconds West.