Full-scale construction began in 2005 with production originally planned for 2007, but the mine experienced a catastrophic water inflow in October 2006, which flooded the mine. A second inflow occurred in 2008 during the first attempt at dewatering the mine after sealing the initial inflow. Remediation efforts continued, and re-entry was successfully accomplished in 2010. Production was delayed several times with the startup dates being announced for 2011, 2013, and 2014. On 13 March 2014, ore production began at the mine, with the mining system and underground processing circuits operational and
uranium ore transported to the
McClean Lake mill operated by
AREVA Resources Canada located northeast of the minesite. The deposit is located at depth of , surrounded by and isolated within a layer of water-impermeable
illite-
chlorite clay, within the Athabasca Sandstone
formation. Its age is estimated to be 1.3 billion years. Due to natural containment and lack of any traces of radioactive elements on the surface, the deposit is used as an example of an effective natural
deep geological repository. During 2020, production was temporarily suspended over two periods due to the risks posed by the
COVID-19 pandemic: from March until September; and then from 14 December 2020. Production at
Orano's McClean Lake uranium mill, which processes the ore from the Cigar Lake mine, was also suspended. The
Canadian Nuclear Safety Commission took regulatory action against owners
Cameco in October 2022 due to the volume of waste material placed on waste pile C.
Cigar Lake Airport, which services the mine, is located southwest of Waterbury Lake. == Reserves and resources==