CALGARY -- The Alberta Energy Regulator says it doesn't agree with a presentation given by a senior executive earlier this year that pegged the cost of cleaning up after the oil and gas industry at $260 billion.

In an email, it says it currently calculates the sector's accumulated environmental liability at $58.65 billion.

The $260-billion figure comes from speaking notes for a presentation in February by Robert Wadsworth, vice-president of closure and liability, as first reported by the National Observer.

In a graphic illustrated by a huge cartoon bag of money, the presentation estimates Alberta's liabilities at $130 billion for mining projects, $100 billion for conventional oil and gas and steam-driven oilsands, and $30 billion for pipelines.

In its response, the AER said the numbers represent a scenario that's "highly unlikely" to develop and points out that regardless of estimates, the industry will ultimately be responsible for paying for its environmental damage.

Premier Rachel Notley says issues emerging from the presentation are being examined by Environment Minister Shannon Phillips, adding the industry's environmental liabilities have accumulated over the past 47 years and can't be repaired overnight.