Dave Burdeniuk says about $2 million dollars worth of natural gas was burned during the week-long fire at the Transgas storage facility near Prud'homme this month.
He says there are also the costs of specialized fire teams, a destroyed wellhead, and other infrastructure damage at the surface.
But Burdeniuk told radio station CKOM that the Crown corporation is only on the hook for $500,000 — its insurance deductible.
Burdeniuk added that any rise in premiums resulting from the fire will be negotiated with the insurer going forward.
As for the investigation into the Oct. 11 explosion, Burdeniuk said no cause has been determined.
He says the damaged wellhead has been sent to Calgary for analysis, but in order to examine the casing pipe leading down into the cavern, the remaining natural gas will have to be removed.
"Right now all the other caverns at Prud'homme, the other six caverns are full. So we don't have anywhere to put that gas," he said.
Once space is freed up, crews will have to fill the cavern with water to displace the gas, a process which could take up to six weeks. The dropping temperatures make this process unfeasible until spring.
SaskEnergy estimates that 665 terajoules of natural gas was lost during the fire, or about 90 per cent of the cavern's capacity. Burdeniuk said the company has already purchased the replacement supply.
Four families within two kilometres of the site were forced from their homes for a week after the explosion.
TransGas is a subsidiary of SaskEnergy.