Cleanup plan gets nod

Boliden (BOL-T), whose Los Frailes mine was shut down by a tailings dam failure on April 25, now estimates that repairs to the dyke and remedial work downstream from the break could put the mine back into production in about six months.

Boliden’s cleanup plan, approved by national and Andalusian provincial authorities, centres on excavating and hauling sludges and on treating soils with lime wherever there is significant residual acidity. The agencies authorized Boliden to dispose of the sludges either in a repaired tailings impoundment or in the mined-out Aznalcollar open pit.

Boliden concluded an agreement with the Andalusian Federation of Farmers and with local authorities to advance funds to compensate for the loss of marketable crops. Boliden will hire an independent consultant, to be supervised by the Andalusian government, to determine the losses suffered by farmers downstream.

Consumers had been avoiding local produce for fear of contamination, making it almost impossible to sell. The farmers’ federation had previously estimated the loss at US$10 million, but Boliden estimated it might be required to pay out US$6.5 million under the agreement.

Boliden said satellite imagery of the area showed a 21-sq.-km area had been inundated by the 5-million-cubic-metre spill. The total land under cultivation in the area amounts to about 5,000 sq. km.

The failed dam, built by a previous operator to store wastes from the Aznalcollar copper-zinc mine, dates to the late 1970s. Aznalcollar, opened in 1979, was bought by Boliden in 1987 and operated until 1996.

The Los Frailes dam is the third tailings-containment structure to fail at a Canadian-owned operation overseas. In March, 1996, a concrete seal in a drainage tunnel beneath a mined-out open pit failed at the Marcopper mine in the Philippines, where Placer Dome (PDG-T) then owned a 39.9% interest.

About 1.5 million cubic metres of tailings stored in the pit escaped, silting up the Makulapnit and Boac Rivers.

At the Omai gold mine in Guyana, owned by Cambior (CBJ-T) and Golden Star Resources (GSC-T), a tailings dam failure in August of 1995 released about 3 million cubic metres of waste water, containing 28 parts per million cyanide and large quantities of suspended silt, into watercourses that flowed into the Essequibo River. A Commission of Enquiry appointed by the Guyanese government subsequently found no criminal liability attached to the owners or contractors, but left the door open for civil actions.

One such action is to be heard May 28 in Quebec Superior Court: a class action claiming damages of $69 million on behalf of 23,000 residents downstream from the mine. The action is being managed by Recherches Internationales Quebec, an advocacy group formed “to represent the interests of the Omai victims.”