[acn-l] Canadian Mine Spill in Spain (fwd)

Rob Huntley (rob at acn.ca)
Sun, 10 May 1998 10:55:52 -0400 (EDT)

This is a forwarded message.
Please direct and/or copy correspondence to the original source.

---------- Forwarded message ----------
Date: Sat, 09 May 1998 12:57:55 -0300
From: "Gary Gallon, Canadian Institute for Business & Environment"
<cibe at web.net>
Subject: Canadian Mine Spill in Spain

  Canadian Institute for Business and the Environment
  Institut Canadien du Commerce et de l'environnement
    506 Victoria Ave., Montreal, Quebec H3Y 2R5
      Ph. (514) 369 0230, Fax (514) 369 3282
               Email cibe at web.net
                  May 10, 1998




A section of a mine tailings pond operated by Canadianbased
mining company, Boliden Ltd., failed April 26, 1998 spilling
waste soil containing toxic metals including zinc, lead, and
cadmium along a 20 mile section of the Guadiamar River, in Spain
contaminating the aquifers feeding the Donana wildlife reserve,
and ruining 6,000 hectares of nearby farmland. The more than
five million cubic metres of sludge contained high levels of acid
used to leachate out the precious metals from the soil before it
was disposed in the tailing pond. Called the Los Frailes mine,
the operation was opened a little more than a year ago on Spain's
"Pyrite Belt" which has been mined since Roman times for its high
grade silver, lead and zinc. The new operation was based on hightech
openpit mining designed to crush millions of tonnes of dirt containing
lowgrade amounts of zinc, copper and silver. The new tailings pond was
built on the old site which was not designed to take so much more waste
dirt from the much larger milling operation.



The environmental disaster has resulted in a huge economic loss
for the mining company and for the other economies in the region.
For the mining company and its insurance companies clean up,
restoration, and reparation costs will exceed an estimated $10
million. In addition, the mine will loss several millions of dollars
more in revenue from what it would have earned if the mine had
remained open. It is currently closed for an indefinite time while
the tailings pond dam walls are repaired and reinforced.

For the farming, fishing, and tourist industries, the spill will cost
them in excess of $200 million in revenues over the next two years.
The Spanish agricultural business association for the region called
COAG Andalucia estimated the longterm loss of productivity from
the contaminated farmland at $113 million. The question now becomes
— is Greenpeace and the other environmental organizations better
economists for the mining companies since they can help companies
avoid such expensive mining disasters?



Tailings ponds are not really ponds. They are soil containment
areas that will eventually be filled to the brim with wet crushed
dirt from the metal extraction (milling) process. However, the
waste dirt is loaded with residual water from the mill slurry process.
Then rain and snow melt can add millions of gallons more water
to the dirt turning it into muck, turning the waste site into ponds
of mud.

The proper construction and maintenance of a tailings pond is
expensive. And it is a backend expensive not involved with the
actual extraction of the minerals. Mining companies have to be
careful to allocate adequate financial resources to ensure the
integrity of the ponds. There is a tendency to cut corners and not
spend enough to build and maintain proper ponds because it is so
expensive and not a part of the cost of extracting the valuable metals.

The tailings pond wall is built like a pyramid, usually using the
tailings soil (to save money) to construct the wall. The base of the
wall is called "the toe". There is an upstream side that holds in
the watery mud, and a downstream side. At the top there is several
feet of "free board" sticking above the pond, with a "crest" on top
that includes a dirt road for driveby inspections.

"The trick," according to Geotechnical Engineer Steven Vick, a
mine waste impoundment expert, "is to ensure both physical and
chemical stability of the tailings deposit" by creating welldesigned,
permanent impoundment structures. However, Vick adds, "this is no
simple thing." Tailings impoundments are susceptible to incidents of
slope instability, foundation seepage, seasonal rainwater overflows,
structural collapse, erosion, and earthquakerelated failures, reports the
Policy Center in Washington, D.C. website 

A number of methods are required to ensure that the pressure on the
wall is not too great and to make sure that not too much water is seeping
through the wall to undermine its integrity. One such method is to use
"piezometres" to measure the water pressure build up in the pores of the
soil of the walls. When the pressure gets too high or the dirt walls too
wet, action must be taken immediately to bring the pressure down. Other
measures that can be taken to reduce the risk of spills include

o   reduction of water within the tailings impoundment
by emergency diversion of contaminated water to the river

o   beaching (placing solids on dry land) of tailings to
minimise free water against the embankment face and
enhancement of tailings consolidation and stability

o   construction of a rockfill/filter buttress against the
downstream face of the tailings wall

o   construction of a toe buttress downslope of the tailings
embankment to reinforce the original wall



Why would Canada's Boliden Ltd., fire one of its professional
engineers, Manuel Aguilar Campos, who worked for the
Spanish subsidiary of the Los Frailes mine for 19 years? He
wrote a detailed report describing the problems with the tailings
pond and the need to make major costly improvements to ensure
the integrity of the dam walls. Instead of being let go, he should
have been retained and his recommendation acted upon. It would
have saved the company millions. In separate warnings, Pablo
Arambarri and two other Spanish scientists warned in a scientific
publication in 1996 that the residues from the old mine tailings
pond site were already leaking into the river representing a "chemical
time bomb for the nearby Donana National Park.



Marcopper Copper Mine, Philippines

>From March to June 1996, 4 million tonnes of toxic tailings
sludge containing toxic metals including copper and zinc
discharged from an old drainage tunnel from the tailings pond of
Marcopper Copper Mine, in the Philippines to the main river system
of Marinduque Island south of Manila. Marcopper was operated by
Vancouver's Placer Dome Ltd., which also owned 40% of Marcopper.
The Philippines Government filed criminal charges against three of the
mine executives. A subsequent United Nations assessment mission
found that there was a "total loss of the use of the rivers for livestock,
fishing, laundry, bathing and agriculture", for the villages along the rivers.

Omai Gold Mine, Guyana

In August 1995, the Omai Gold Mines 65% owned by Montreal
based Cambior Inc., experienced a major tailings spill in Guyana,
severely polluting the Omai and Essequibo rivers with cyanidelaced
contaminants.  A tailings pond dike crumbled spilling an estimated
3 million cubic metres of contaminated mine wastes, enough to fill
a onekilometerhigh tank with a base as wide as a football field.
Three days after the accident, Guyanese President, Cheddi Jagan,
declared 80 kilometers of the Essequibo River an environmental
disaster zone. There were warnings that the tailings pond dike was
not properly maintained when there had been three smaller cyanide
spills in the first half of 1995.

Galactic Resource Corp., Colorado

In 1991, Summitville Mine in Colorado, owned by Vancouver's
Galactic Resource Corp., gave the United States one of its largest
tailings disasters in history. It was a continuous spill over a one year
period from a heapleach gold mining processing site where cyanide
was dumped onto huge outdoor piles of lowgrade ore over a 50 acre
area."Literally, there was 1,000 to 2,000 pounds of heavy metals daily
leaving the site in dissolved form flowing into Colorado's Whiteman
Fork River that flows into the Alamosa River. There was no life in the
river for 17 miles."  It was "the Exxon Valdez of the American mining
industry," stated Thomas Hilliard, formerly of the Washington, D.C.
based Mineral Policy Center. The U.S. Environmental Protection Agency
shutdown the mine in 1992, initiated legal action and requested the company
pay for the millions of dollars in clean up and reparations. The operation
went bankrupt.



When mining companies and local governments collaborate to get a
mine up and running, the proper strict enforcement of environmental
law will result in long term economic gain, even though it will cost
the mining company more up front. Canada has not experienced the
same kinds of mine tailings ponds disasters as its Canadian companies
have overseas in the past ten years. That's because the federal
government and the provinces have been enforcing strong environmental
laws in this country. Designed to protect fish, wildlife and water quality,
the environmental laws, have had the collateral effect of protecting and
enhancing the economies of the mining companies and the local



Management of tailings ponds is an expensive environmental responsibility.
Built and maintained properly tailings ponds don't spill. It is important
that the Mining Association of Canada (MAC) develop voluntary
environmental measures for its companies to apply across all of their
operations inside and outside Canada. Sitting on the Executive Committee
of the Board of Directors of MAC are Louis Gignac, Cambior Inc., and
Jay Taylor, Placer Dome. It may be that ISO14000 Environmental
Management Systems may have to be applied Or, it maybe it is time
for Environment Canada and the Canadian Environmental Assessment
Agency to step in and provide assessments and guidelines for the proper
management of Canadian mining operations overseas. The Mining
Association of Canada website  http//www.mining.ca/english/. Contact
Mrs. Justyna Laurie-Lean, Vice President, Environment and Health,
e-mail  jlauriel at mining.ca



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      Copyright (c) 1998 Canadian Institute for
       Business and the Environment, Montreal
              All rights reserved.

Gary Gallon
Canadian Institute for Business and the Environment
506 Victoria Ave.
Montreal, Quebec H3Y 2R5
Ph. (514) 369-0230, Fax (514) 369-3282
email: cibe at web.net