Compiled by Al Gedicks, Exec. Secretary
210 Avon Street #4
La Crosse, WI 54603-3097
(608) 784-4399
Revised and Updated, August 1999
Environmental Aspects Socio-Economic Aspects Cultural Aspects Sources

Note: Sources are footnotes indicated in report by ( number).

Environmental Aspects

1. Basic description of Exxon/Rio Algom's  proposed mine. 

Exxon sold its 50% interest in the project to Rio Algom in January 1998.  Afterwards, Rio Algom changed the name from the Crandon Mining Company (CMC) to Nicolet Minerals Co. Exxon still owns the mineral rights to the deposit and retains a profit-sharing agreement with Rio Algom under terms of the sale.

a. one of the largest zinc/copper deposits in North America  (source: Exxon Coal and Minerals: A Profile, 1991, p. 4) The ore body itself is a vertical slab about one mile in length, averaging 200 feet in width, and extending to a depth of 2800 feet. Exxon proposes to dig an underground mine to extract 55 million tons of rock while recovering about two million tons of zinc-copper ore over about 28 years. 

b. these minerals are found as massive sulfides, or rocks formed by minerals in combination with sulphur. Unlike iron mining, sulfide rock can produce sulfuric acid, as well as high levels of poisonous heavy metals like mercury, lead, zinc, arsenic, copper and cadmium,  when exposed to air or water during and after mining.  Acid mine drainage is generally regarded as potentially the single largest cause of negative environmental impacts resulting from mining. (1)

c. problems of acidity and radioactivity are linked: acid formation will lower the pH of the water and lead to the further dissolution of  radionuclides, metals, and other toxic substances.(2)  Exxon and the DNR admit there is uranium in the orebody but emphasizes that there are only trace amounts that do not exceed the background levels found in most types of bedrock(3).   However, in a survey of various sulfide mines producing copper, lead and zinc, the U.S. Environmental Protection Agency found that even where the total uranium content was below detection levels, radon daughter concentrations were at levels which posed potential health hazards to mining personnel.(4)

d.  mine wastes have poisoned over 12,000 miles of rivers and streams, according to the U.S. Bureau of Mines. The release of mine wastes into the environment has resulted in many cases of fish kills, such as the dramatic trout kill on Montana's Clark Fork River and the recent toxic mine sludge spill that flooded rivers and farms in southern Spain in April, 1998. The latter disaster involved the rupture of a mine tailings dam dyke near Spain's Donana National Park. The toxic sludge burst from a mine resevoir of a nearby Canadian-owned zinc mine and left a thick layer of zinc, lead, iron and cadmium along a path of more than 20 miles. A local farmers' association says some 15.000 acres of croplands have been affected.(5)  About 60 Superfund sites are abandoned mines. More than a dozen of these are currently active and pose both human health and environmental problems.(6) 

e. Because of the location of the proposed mine at the headwaters of the Wolf River, in an area with high rainfall and numerous wetlands and streams, Exxon's own engineer said "You couldn't find a more difficult place to mine."(7) 

2. The largest toxic waste dump in the history of Wisconsin

a. over its lifetime, the mine would generate about 44 million tons of wastes. Half of the waste--rocky "coarse tailings" would be dumped to fill up the mine shafts. The other half of the waste--powdery "fine tailings"--would be dumped into a waste pond about 90 feet tall and covering 355 acres. At a size of about 350 football fields, it would be the largest toxic waste dump in Wisconsin history.  It would be larger than most towns in the state. The latest revision to the waste disposal plan calls for the company to remove the pyrites (sulfide mineral) from the waste rock and put the pyrite concentrate back in the mine as cemented backfill, while the remaining tailings would be sent to the the tailings management area (TMA) on the surface. One result of the pyrite separation would be a reduction in the size of the proposed TMA. The area and volume of the TMA may be reduced by approximately 25% from its original proposal.

b. even if the company invests additional dollars in pyrite separation, that would still leave about 1% or more sulfides. This would have the potential to form acid mine drainage and would still have to be isolated from the environment forever. Nicolet proposes to put a cover on the top and a liner on the botttom.(8)  Basically, we're talking about a big plastic bag sitting at the headwaters of the Wolf River.  All liners leak.(9)   The Wisconsin DNR says that as presently designed, the proposed clay liner at the bottom of the mine waste "would not provide adequate protection to the groundwater."(10)   According to Jerry Goodrich, former president of the Crandon Mining Company, the plastic liner underneath the toxic mine waste will dissolve in 140 years. "We're saying after 140 years it vaporizes. It's gone."(11)

c. The monitoring wells discussed in Exxon's Environmental Impact Report (EIR) would not be able to detect a leak from the tailings pond because any leakage will not migrate laterally away from the cells, but rather will be driven downward by the groundwater gradient pattern created by the cells themselves.(12)  The U.S. Fish and Wildlife Service criticized CMC for failing to take into account the long term ground water contamination from the mine/mill which could persist for 9,000 years.(13) 

d. future generations will face the ever-present threat of the mine waste ponds either flooding or collapsing. A 1996 report by Mining Journal Research Services concluded that the most important factors for predicting tailings dam failures concern water-handling in one form or another.(14)  The mine site is a water-rich environment that is especially prone to heavy rainfall and snow melting. The geo-clay membrane covering the mine wastes will be 0.24 inches thick and will be exposed to many cycles of wetting and drying, thus increasing the potential for deterioration of the cover liner. To predict the stability of the waste ponds over time, it would be necessary to treat the waste ponds as "topless tubs subject to recharge, filling and overflow."(15)   Exxon has not done this.  The U.S. Fish and Wildlife Service says that the waste dump "should either be designed for guaranteed protection of the resources in perpetuity, or the project should be postponed until such technology is available."(16)  The lesson of the recent mine waste disaster in Spain is that the best available technology at the time may be inadequate to stand the test of time.

e. the backfilled mine will have another 22 million tons of tailings stored here - an amount equal to the amount stored in waste ponds on the surface. However, the mined out area is not designed as a mine waste disposal facility. This underground area will have open voids remaining in the shafts and groundwater will flow through these mine wastes forever. This area is only 500 feet from Little Sand Lake, which drains through the Town of Ainsworth to the Wolf River.(17)   Moreover, Nicolet's plan to put the concentrated pyrite (acid-generating material) back into the mine increases the likelihood of acid mine drainage after mine closure when the groundwater comes in contact with the sulfide waste. This scenario has already occurred at the Dober mine in Iron river, Michigan, where groundwater came in contact with pyrite in the abandoned mine and resulted in acid mine drainage that killed fish in the Iron River downstream from the mine. This mine closed in 1968. The operator did not backfill the abandoned mine with concentrated pyrite, as Nicolet Minerals proposes to do at Crandon. Nevertheless, the pyrite in the abandoned mine was sufficient to cause a major contamination problem once groundwater came into contact with the pyrite and made its way into the Iron river in Michigan and the Brule river just across the border in Wisconsin. The Michigan DNR reported that 10.5 miles of the Brule, downstream from the Iron river, was affected by the same acid drainage problem at Dober.(18) 

f.  At Rio Algom's Elliott Lake uranium mines in Ontario, Canada, tailings containing 3% total sulfur are capable of producing acid rock drainage and will require neutralizing control measures for an indefinite period into the future.(19)

g. there are no examples of successfully reclaimed metallic sulfide mines where the mine is closed, the water treatment plant is shut down and the water runs pure and clean. The U.S. Forest Service says that "there are major technical uncertainties associated with the prediction of acid drainage potential at the time of mine plan approval as well as with mitigation or treatment techniques for post-mining use."(20)  In other words, if you can't predict which wastes will result in acid drainage, you can't develop controls to prevent acid drainage. Once started, acid drainage cannot be shut off; it becomes a "perpetual pollution machine."(21) 

h. CMC's own plans for containment of the mine wastes have been criticized as inadequate and lacking scientific support by an independent mine waste expert hired by the former Public Intervenor.(22)

i. there is no evaluation of the potential risks of the wastes that will be generated by the laboratory to be constructed on the mine site. Over the course of the life of the mine, the laboratory is projected to produce more than a half million pounds of waste. The composition of these wastes needs to be evaluated to see if they are compatible with other waste streams and with the containment system.(23) 

j. there is no evaluation of the impact of circulating sanitary water from the mine facilities to the tailings management areas (TMA). Circulating sanitary water into the TMAs could provide the necessary nutrients for bacteria that could greatly increase the rates of acid generation.(24) 

k. In 1995 and again in 1997 and 1998 , the national conservation group American Rivers added the Wolf River to its list of the nation' 10 most endangered rivers due to the pollution threat posed by the proposed CMC mine. The Wisconsin State Council of Trout Unlimited has passed a resolution opposing any permits for the proposed mine.(25)  In August, 1999, the Federation of Fly Fishers listed the Wolf River as the most endangered fishery in the nation because of the threat from metallic sulfide mine pollution. "No copper sulfide mine has ever been successfully mined anywhere in the world," said Bob Molzahn, chair of the Endangered Fisheries Committee. "It's frightening to think we would risk this magnificient and irreplacable waterway with a technology that is unproven, and with such a tremendous potential for environmental devastation."(26) 

3. Groundwater Drawdown

a. Exxon's proposed mine could cause a drastic and irrreparable drop in the water levels of  lakes and streams in a four-square mile area. Over about 28 years, it would pump out up to 1,000 gallons of water per minute, over one MILLION a day, from the half-mile-deep shafts.(27)   According to the Public Intervenor, "the protection of public rights in water is an absolute limit on DNR's ability to permit this project, so this issue becomes crucial."(28) 

b. "One of the most serious oversights in the discussion of potential environmental impacts in the EIR is the failure to note that the simple act of drawing down the water table or changing the saturation profile in soils above the water table will create ground-water contamination. Sulfate, total dissolved solids, and metals (particularly arsenic) contamination of groundwater, particularly in forested terrains in humid climates and in areas with recharging wetlands, can be expected solely by creating a ground-water decline. In areas like the permit area, a strongly reduced zone develops in the soil profile that accumulates sulfur stored as sulfide minerals.  Decreasing the water table (or dropping the saturation profile) brings oxygen into contact with these sulfide minerals, essentially producing in situ acid drainage....Without spilling a drop of process water and while perfectly containing all tailings waste leachates, CMC can, and likely will, produce significant ground water contamination just by creating the cone of depression."(29) 

c. there is serious disagreement between DNR consultants, CMC and Dr. Douglas S. Cherkauer, an independent expert on groundwater hired by the Public Intervenor on the key issues of  the connection between groundwater and area lakes. CMC and its consultants have argued there is little, if any connection, between the lakes and the groundwter system. If this groundwater model is accepted, the data would seem to show  an insignificant water drawdown from mine pumping.

d. this is exactly the scenario that occurred during the permitting process in the 1980s. "Exxon at that time designed its model so as to minimize likely impacts on the lakes. When the model's shortcomings were pointed out, Exxon essentially refused to modify the model to simulate a reasonably conservative set of conditions."(30)   Based on an examination of CMC's data,  Dr. Cherkauer concluded that the data do not support CMC's argument of minimal connection between the lakes and the groundwater. Quite to the contrary, "The lakes currently provide recharge to the groundwater system. Declines in ground-water heads due to mine pumping will induce more water to flow out of these lakes, thus upsetting the water balance of their water budgets."(31)  This is like the bottom of a bathtub when the water is draining out.

e. company assurances that the mine will not significantly drop stream levels are based on inaccurate reporting of existing flows, according to Dr. Cherkauer. Stream flows used by the company are lower than those recorded by the U.S. Geological Survey.(32) 

f.  divers in Little Sand Lake, less than a mile from the mine site, have confirmed the existence of spring holes in the bottom of the lake. The U.S. Geological Survey has confirmed that rock samples taken from the lake bottom indicate groundwater spring activity fed through the lake bed.(33)   The DNR has done further drilling at the site to determine the extent of this connection.

g. in order to mitigate the groundwater drawdown, CMC proposes to pump water from deeper levels of the aquifer. According to Dr. Arthur S. Brooks, a biologist hired by the Public Intervenor, "the net effect of mitigation pumping will be to alter the natural flow of groundwater and to disperse toxic metals from the project site through a diffuse system of streams and lakes."(34) 

h. The U.S. Army Engineer Waterways Experiment Station said that Exxon/Rio Algom's groundwater model is "not suitable" to analyze the potential effects of groundwater drawdwon. Instead, they recommended that the modeling be done by independent scientists because "with even state-of-the-art models one could bias the results to show any desired result from the project."(35)

i. the changes proposed for the groundwater model will not be adequate to predict worst case scenarios for water drawdown around the mine. "This is because the model violates fundamental physical properties of groundwater flow systems that must be adhered to when constructing a model, and that are ignored in the present (and presumably redefined) model."(36) 

j. No regulatory agency in the U.S. has ever used groundwater computer modeling in their mine permitting process.(37) 

4. Wastewater Discharge to the Wisconsin River

"If we can't protect the Wolf, there'll be no Crandon mine."  Jerry Goodrich, former CMC president.  Appleton Post-Crescent  4/24/95.

a. the day after American Rivers designated the Wolf River as a threatened river in 1995, Exxon announced it was abandoning its plans to dump treated waste water into the Wolf River. Instead, the company said that it would build a 40-mile pipeline and divert the waste water into the Wisconsin River near Rhinelander.  Because the Wisconsin River is not as protected as the Wolf, the company would not have to spend as much treating the discharge.

b. this new plan threatens pollution of both the Wolf and the Wisconsin rivers. The threat to the Wolf remains because the mine wastes would still be stored at the headwaters of the Wolf. The discharge of waste water into the Wisconsin could result in the bioaccumulation of heavy metals in aquatic organisms and changes in the natural species composition of the river.(38)   The Wisconsin State Council of Trout Unlimited has said that "Wastewater that is unacceptable to an 'Outstanding Resource Water' like the Wolf River is no more appropriate to discharge below a paper mill and hydroelectric dam on Wisconsin's namesake river."(39) 

c. the plan could actually increase groundwater depletion in the area of the mine because of the amount of water necessary to pump the wastes to Rhinelander.

d. the DNR has already gone on record as saying that the biochemical oxygen demand (BOD), which is necessary for fish to survive and reproduce is already "fully allocated" at the proposed discharge point, meaning that no further BOD can be allowed. The only way that Exxon would be allowed to discharge pollutants would be if other industries upstream would lower the amount of pollutants they discharge. Rather than tell Exxon they can't use the Wisconsin River as a sewer for their mine waste, the DNR is studying a "reallocation" of existing discharges to see if there is room for Exxon's new pollution.(40) 

e. the DNR  is also ignoring evidence that sediment in the Wisconsin River contains high levels of mercury. Previous to Exxon's plan to dump its mine wastewater, mercury had been listed as a dangerous, poisonous pollutant in the Petenwell and Castle Rock flowages downstream from Exxon's proposed discharge. The addition of sulfates from Exxon's mine wastewater would increase the level of mercury in the river and in the fish.(41) 

f. The planned discharge would involve transferring waters of the state from the Great Lakes basin (Wolf River Watershed) into the Wisconsin River within the Mississippi watershed for a period up to 30 years. It is not clear what will happen to the water levels and temperatures in the Wolf in times of drought and low flows. The Wolf River is a world class trout stream and water temperatures are critical to the survival of sensitive species.

g. Federal law, namely, The Water Resources Development Act of 1986 (WRDA) prohibits "any diversion of Great Lakes water by any State, Federal agency or private entity for use outside the Great Lakes basin unless such diversion is approved by the Governor of each of the Great Lakes states." Exxon claims that because it is withdrawing groundwater instead of surface water, Great Lakes water is not being diverted. The WRDA, however, makes no such artificial distinction between groundwater and surface water.  The Wisconsin DNR supports Exxon's unique interpretation of the WRDA and claims that Wisconsin has sole decision-making authority regarding this international issue. The Army Corps of Engineers also determined that the interbasin transfer of water is legal.(42) 

h. Eight environmental groups filed a lawsuit charging that the Army Corps of Engineers ignored federal law when it ruled that Exxon's plan to pump ground water from its proposed underground mine is not covered by the 1986 federal law governing diversions of water from the Great Lakes or any of its tributaries. "It is a very simple lawsuit," said Albert Ettinger, an attorney for the Environmental Law and Policy Center in Chicago, one of eight plaintiffs. "The Corps has taken a very narrow reading of the statute to protect the Great Lakes...Ground and surface water in the area of the proposed mine are interconncted so removal of ground water will prevent it from reaching streams and lakes that are a tributary of the Great Lakes."(43) 

i. Under increasing criticism for its wastewater pipeline to the Wisconsin River, Nicolet Minerals Co. has proposed to treat the water at the mine site and put it into a seepage basin, from which it would return to the groundwater.(44)   Rio Algom's proposal assumes that it would be possible to significantly reduce the amount of water flowing into the mine by placing grout (a cement mixture) over the entire ore body. If the mine inflow can be reduced, there would be less water to treat and discharge into the seepage basin. However,the company's grouting tests failed to stop the inflow of water. Returning treated mine wastewater to a seepage pond is based upon the unfounded assumptions that the Nicolet Minerals Company can accurately predict the mine inflow from the surrounding bedrock and that this inflow can be redued by grouting. The company has never performed adequate testing, such as an aquifer pumping test, to figure out where the water draining into the mine will come from, or where it will go after mining. Instead, the company has relied upon faulty computer models to make projections that independent experts have consistently rejected. Regardless of the amount of water to be treated, the discharge of mine wastewater into seepage basins would ultimately allow pollutants to contaminate water flowing into the Chippewa's wild rice lake and the Wolf River watershed. Rio Algom's proposal is simply going from the fire into the frying pan. 

j. Nicolet Minerals is still treating the wastewater pipeline as a possible alternative to the seepage ponds which may be resurrected if ongoing problems in the company's groundwater model cannot be resolved to the satisfaction of the Army Corps of Engineers and the U.S. Geological Survey.
Environmental Aspects Socio-Economic Aspects Cultural Aspects Sources


Wisconsin Resources Protection Council | MAIN OFFICE: Box 263, Tomahawk, WI 54487 
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