2011 Update: Risk Reduction Planning and Environmental Assessment

SRC is managing the development of a risk reduction plan for the Lorado tailings site. To begin, a status quo risk assessment was done to determine the risks currently posed by the site to human health, aquatic and terrestrial wildlife and the environment. SRC and its consultant, Golder Associates, met with local residents in December 2010, and regulators in February 2011, to seek agreement on the desired endpoints for the site. With this information, a conceptual risk reduction plan for the site is being developed.

Several options for the remediation project are being assessed. These were discussed with the residents of Uranium City and with regulators in June of this year. Golder is proceeding with more analysis related to covering the tailings and treating the water of Nero Lake. Once a preferred option is chosen it will be discussed with the residents of Uranium City. Then an environmental assessment of the proposed project will be done and submitted to the federal and provincial regulators as an environmental impact statement for the proposed project.

Site Locations

Lorado Uranium Mines Limited operated both a mine and a mill at two separate locations near Beaverlodge Lake, in northwest Saskatchewan.  The Lorado mill site is located approximately eight kilometres south of Uranium City on the west side of Nero Lake. The Lorado mine site is located 2.5 kilometres south of Hansen Bay, Beaverlodge Lake approximately 12 kilometres south of Uranium City by road.

General Description

Lorado Mill

The Lorado mill was operated from 1957-1960 by Lorado Uranium Mines Ltd. It was designed to treat ore from the Lorado mine and from other satellite mines in the region.  Ore was hauled from the Lorado mine and satellite mines for processing at the mill.

The mill was designed to process 750 tons of ore per day; however, the actual amount processed was much less due to depleting reserves and milling problems. The treatment consisted of a sulphuric acid leach and an ion exchange process for uranium extraction.  The mill ceased operations in April 1960 due to a lack of feeder ore from the Lorado mine and satellite mines.  Estimates of the total amount of ore processed at the Lorado mill range from 305,000 to 545,000 tonnes.

Tailings from the mill were deposited in a topographic depression to the east of the mill facility. Eventually the low area filled, and the tailings extended into Nero Lake. The total volume of tailings is estimated to be 227,000m³, of which 50,000m³ is under the water of Nero Lake. The exposed tailings, covering approximately 14 hectares, are located adjacent to Nero Lake. The tailings are acid producing, in part due to the oxidation of pyrite in the tailings and also to the discharge of the acidic process solution used in the mill. The acidic conditions in the tailings result in the mobilization of soluble metals and radionuclides, which eventually drain into Nero Lake.

The Mines Pollution Control Branch of Saskatchewan Environment organized and oversaw the demolition of mill buildings on the Lorado mill site in 1990. The work involved dismantling the mill, salvaging some uncontaminated material, and burning/burying the remaining debris. The entire mill site area was then recontoured with unconsolidated material.

Lorado Mine

Lorado Uranium Mines Ltd. acquired the site in 1953 after several uranium showings had been outlined by diamond drilling. To develop the showings, a vertical shaft was started in 1954 which ultimately reached a depth of 213 metres with four horizontal working levels.

By 1959, reserves had considerably decreased because of the inability to trace mineralized zones in the deeper levels of the mine. The mine was closed in 1960.

Access to the Lorado mine was via a single, vertical shaft, measuring five by five by 214 metres deep. The condition of the shaft cap is difficult to assess as it is currently covered with waste rock. There is a large amount of waste rock in the area, some of which has been used for foundations and road construction in the area.

There are two foundations associated with the shaft that are in good condition and pose little risk. There is a small amount of debris in the shaft area including scrap material and old wooden water lines. There are no buildings standing on the site and a large portion of the debris from these buildings has been removed.
 

An aerial shot of the Lorado mill site which is located approximately 8 kilometres south of Uranium City on the west side of Nero Lake.