PCA closes Saskatoon mine due to heavy water inflow problem

After nearly 22 years of operation, Potash Co. of America is stop- ping operations at its Saskatoon mine, with resumption not anticipated until mid-1988.

Heavy inflow of water is the cause, says Ken Culver, manager of corporate relations for Rio Algom Ltd. which holds 87.8% of PCA.

The inflow of water is currently about 5,000 gallons per minute and further increases in the rate are probable.

The mine’s water problems became evident this past summer when inflow was approximately 300 to 400 gallons per day. With inflow gradually increasing, a $15-to-$20- million program was announced this past November to tackle the problem.

That program, which was to last approximately eight months, would have involved the construction of 14 plugs to isolate the area of water inflow from the active mine workings with minimal disruption to current production levels.

However, as the water flow increased dramatically, explains Mr Culver, it became apparent the work schedule for the 14-plug program could not be met. It was decided to save the two existing mine shafts by constructing plugs at the bottom of each shaft.

These two plugs will seal off and isolate the existing workings and keep the shafts available for access and mining of other areas of the company’s potash deposits, says Mr Culver.

It’s expected to take three or four months to complete this program, he says. In the meantime, there are a number of studies under way to determine the most economic method of redeveloping the deposit for production.

One possibility being considered is re-entering the mine via the shaft to the north and employing the standard potash mining technique. Solution mining is also being considered as a possibility. Under the second scenario the potash and water solution would be brought to the surface and the potash precipi- tated out.

It’s still too early to say which method will be put to use at the mine which last year produced 850,000 tons of muriate of potash.

The closing of the Saskatoon mine has caught many in the industry by surprise as it was PCA’s Sussex operation in New Brunswick that was under heavy scrutiny as the disappointing performer. Indeed, in 1985 PCA took a $153.3- million writedown of the Sussex operation.

However, Mr Culver reports that progress at the Sussex operation is on target with design capacity of 700,000 tons expected to be reached by mid-year after pumping in approximately $33 million for underground and surface work.

This is the second project in the past three months that has gone sour for Rio Algom. The first was the transfer in ownership of its East Kemptville tin mine to the banking group that financed the majority of the capital cost of the project. Continuing low prices following the collapse of the world market for tin late in 1985 was the culprit in that case. (N.M., Nov 24/86)

Rio purchased the outstanding shares of PCA early in 1986 for $13 million in cash and the assumption of $151 million in debt. For the nine months ended Sept 30, PCA posted net earnings of $1,006 million versus net earnings of $3.9 million in the year-earlier period. Its cash position at the end of the period stood at $2.25 million, up from $986,000 at the end of the year-earlier period.