Pollution issues at the Idaho Maryland Mine project

The issues discussed in this section relate to concerns about modern day mining practices. We understand that legacy mining techniques were even more questionable.


IMM claims it will release water of drinking water quality into Wolf Creek from its dewatering operations: even MODERN DAY mines using MODERN DAY standards have been found to release cyanide, arsenic, sulfate, lead, mercury, cadmium, copper, nickel and zinc. See more from a 2006 study on modern mine compliance with stated water pollution goals!

Wells were drained quickly and against all assurance in the Siscon Gold mine re-opening on the San Juan Ridge, just recently. Located about 27 km (17 miles) north of Nevada City, it was scheduled to become the largest underground gold mine in California. (see OneMine.org, "San Juan Ridge Gold Mine Begins Production", R. Pease, 1/1/1996) No one knows how many wells, both near and far, could be drained over time by dewatering at the Idaho Maryland site. (See "Special Report: Golden Gamble in Grass Valley, Part 3: Dewatering an Old Gold Mine" on Yubanet.com


GV City Council members pledged to work to reduce ozone in our air. IMM trucks will release hundreds of tons of NOx, and particulates, into our local airshed, thus substantially increasing the formation of ozone. Asthma will be worsened! Information on Air Pollution in general.    Information on Pollution from Heavy Diesel Trucks

Ore Stockpiles

"...ore and development rock is planned to be crushed underground using a primary jaw crusher. The crushed material will then be transported to the surface and placed in surface stockpiles via conveyer. Material will then be drawn from the stockpiles and transported to the processing plant by conveyer." (pg. 3-5, Mineral Project Application, Mineral Exploration and/or Extraction Environmental Assessment, IMM)

  • Will this crushed ore have the potential for acid mine drainage issues?
  • Where will this stockpile be located, and for how long?
  • Will it be protected from rain, from oxidation, from seepage into the ground?
  • Why doesn't this document discuss the extent of and concerns about this stockpiling?

Waste Rock

" If the material is waste rock, it will be considered as sized ceramic feed material and will be conveyed to a series of storage silos adjacent to the ceramics plant" (pg. 3-6, ibid)

  • How many silos, and where will they be built?
  • What precautions will be taken if the waste rock is contaminated?


"Explosives and detonators will be required for drilling and blasting activities underground. These materials will be stored underground in a secured areas."   Again, another set of hazardous materials that need to be stored separately and separately maintained.

Gold Processing / Hazardous Materials

Sodium cyanide (NaCN), a listed hazardous material will be transported to the site in either solid or aqeous form, either in "super sacks" or in tanker trucks.... Acids will need to be stored in a different place to minimize the formation of lethal hydrogen cyanide gas. For details on cyanide at IMM please see this link.

  • This is a 24/7/365 operation. Trucks loaded with these hazardous materials could slip, tip, slide, or get stuck in snow banks or on icy roads in the GV winters.
  • Concern exists that the incompatible hazardous materials might accidentally mix

Other Hazardous Materials

Other hazardous materials to be used onsite include:

  • lime
  • Ca(OH2)
  • sodium hydroxide (NaOH)
  • dilute hydrochloric acid (HCl) for pH control
  • lead nitrate (PbNO3) to enhance gold leaching kinetics
  • hydrogen peroxide (H202) or sulfur dioxide gas (SO2) for cyanide destruction
  • sodium isobutyl xanthate as a flotation collector
  • methyl isobutyl carbinol (MIBC) as a flotation frother
  • soluble starch.

More Issues

  • Additional "minor development work"
  • Exploration and rehabilitation of the mine would commence during the dewatering phase. IMM indicates that "Some minor development work would be required to access certain ore bodies for drilling, to excavate drill stations, to bypass caving-in drifts, and for mine infrastructure." (ESA/205379, pg. 2-20) What does this "minor development work" entail and where would it happen?
  • Barbed Wire
  • "The entire site perimeter (of the Idaho-Maryland portion of the IMM) would be secured with an eight-foot high chain link fence topped with razor or barbered wire except for the main entrance...." ( ESA/205379, Oct. 2008, pg. 2-7) This would be unattractive and interfere with wildlife habitat.
  • Reclamation
  • The IMM proposed project indicates that if the mine re-opens, runs to full production and then closes when the gold ore is depleted, then "...reclamation would be expected to be initated at that time and last for approximately one year." The Wenatchee mine, which IMM compares itself to, required 10 years of reclamation, and then could not be sold without additional promises of reclamation because of continued ground subsidence and remaining toxics in the soil. The IMM mine is proposed several dozen new buildings and major underground work. This estimate is a substantial underestimation

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