De Beers has determined that a raw sewage spill under a dormitory at its Gahcho Kue mine site last month was caused by a crack in a pipe.

A worker at the site reported a "sewage-like smell" inside a dorm on Feb. 16, according to the company's incident summary.

The diamond mine is located about 280 kilometres northeast of Yellowknife at Kennady Lake.

The report says, upon investigation, it was determined that about 1,000 litres of excrement had "formed a frozen sheet" below the dorm.

Access to the dormitory's washroom and laundry facilities were immediately restricted to stop the source of the spill, the report says. The damaged section of the pipe was then replaced and, in order to mitigate the smell, lime was spread over the frozen puddle.

The report says there was no indication that the spill had migrated to other areas of the camp.

De Beers says that a 15 centimetre crack in a sagging plastic pipe, which brings sewage from the dorm to a treatment plant, was to blame for the spill.

The company says an internal investigation revealed that the pipeline was improperly installed.  Measures were taken to prevent more stress on the pipe.

In January, a worker at the site spoke out about safety concerns in the dormitories, including disconnected water lines and mould.