MAC: Mines and Communities

London Calling Scents Something Rotten In The North Woods - And Even Worse In Armenia

Published by MAC on 2007-03-03

London Calling scents something rotten in the North Woods - and even worse in Armenia

by Nostromo Research

3rd March 2007

It all seems a bit peculiar. But a distinct whiff of corruption is in the air as Michigan's Department of Environmental Quality (DEQ) withdraws initial approval for Rio Tinto/Kennecott's nickel-copper mine project in the state. [see BusinessWeek article below].

The significance of this project shouldn't be under-estimated. It marks the first new nickel mine promulgated for years in the USA (Norilsk's Stillwater is the only current producer). It's also Michigan's first sulphide-based one. The neighbouring state of Wisconsin has already effectively banned such mining because of the dangers of uncontrollable acid drainage.

Unusually, it's not Rio Tinto that's currently in the firing-line. Rather, the Michigan state environment agency now finds itself under scrutiny for what - at best - seems woeful negligence and at worst could be the result of a criminal act.

The evidence is that two independent reports on Rio Tinto's proposal were last year "inadequately" vetted (a euphemism for being buried) by the DEQ before conditional approval for the mine was granted in January this year. One of these reports examined the critical question of whether the "crown pillar" (bedrock above the underground excavations) might not collapse once mining was underway.

It determined that the company's design proposal did "not reflect industry best practice", while "the hydrologic stability of the crown pillar has not been considered. Therefore, the conclusions made within the ... application regarding crown pillar subsidence are not considered to be defensible."

Now that's a pretty damning conclusion and one which ought to have sent the company instantly back to the drawing board - if not had the entire proposal being thrown out of court. Mysteriously, however, the report's author later recommended that the mining should proceed while "further analysis is conducted".

Which is rather like sending a boat into the ocean while still caulking its bottom.

No wonder a spokesperson for the National Wildlife Association has demanded to know "What other reports are out there that were not to the staff's liking that have been buried?"

In fact, if the conclusions of a September 2006 report by Earthworks had not been so widely ignored within the US the validity of all pre-mine studies conducted by mining companies should now be strongly doubted.

That report, carried out by an expert team, revealed that almost every appraisal of likely water contamination at around two dozen major mines had underestimated the actual impacts.

Among the mines studied was Rio Tinto/Kennecott's Flambeau mine in Wisconsin which closed in 1997. This is perhaps the closest example to which Michigan's guardians of the environment might have come, in terms of a sulphide operation by the same company in a compatible ecological setting.

The Earthworks’ experts obtained monitoring and compliance data for the period 2000-2003 from the company's Annual Report on Groundwater and Surface Water Trends

This noted that four monitoring wells in the backfilled pit showed "exceedences [sic] of drinking water MCLs or secondary standards for iron (up to 12 mg/l), manganese (up to 37 mg/l), pH (as low as 6.1), sulfate (up to 1,700 mg/l) and total dissolved solids (up to 3,400 mg/l).”

One in-pit well “showed continued increasing or elevated concentrations of iron, sulfate, TDS and manganese”, though other wells showed decreasing concentrations. Groundwater elevations were higher in the backfilled pit than they were between the pit and the river, so water was potentially flowing from the pit to the river.” After groundwater elevations returned to pre-mining levels, concentrations of iron, manganese, sulfate and TDS increased and pH decreased." (In other words, acidity increased).

"Values for pH before pumping began were quite variable (5.8 - ~8.3). Concentrations appeared to peak in 2000 and were slowly decreasing for manganese (from a high of over 5,000 µg/l), sulfate (from a high of almost 700 mg/l) and TDS (from a high of ~1,300 mg/l).” Disturbingly, however, they were "continuing to increase for iron (up to ~6 mg/l).”, while zinc concentrations were variable and (as of 2003) still around 700 µg/l.

"Although concentrations in surface water up and down gradient of the mine showed no temporal water quality trends, a report from the Great Lakes Indian Fish and Wildlife Commission stated that water parameters measured have changed from those measured during mine operation, and that the change makes it impossible to compare during- and post-mining water quality

"The concentrations of copper, iron, manganese and sulfate in the backfilled pit were predicted using geochemical modeling in the EIS. The modeling apparently used concentrations from short-term leach tests, but the details of modeling were not provided in the EIS. Predictions were also made in 1996 and 1997 as part of the mine’s backfill plan. Concentrations predicted in 1997 for copper, manganese, and iron were substantially higher than those predicted in the EIS. For example, copper concentrations predicted in 1997 were 0.18 to 0.56 mg/l, and concentrations in the EIS were 0.014 mg/l."

If that all sounds a little obscure, then consider this: "Compared to EIS-predicted post-mining concentrations in the pit backfill, post-mining concentrations in the backfill were higher by up to 45 times for copper, 70 times for manganese, 30 times for iron, and 1.25 times for sulfate."

"Therefore", concludes the Earthworks report, "modeling underestimated actual concentrations of metals and other contaminants in the pit backfill leachate. "

All things considered, that seems a pretty big under-statement.

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