But no penalties will result because the blowout didn't contravene any regulations, Darin Barter, spokesman for the Energy Resources Conservation Board, said Wednesday.
"There weren't any specific regulations. We require companies to operate safely, but regarding this one, (a rule) wasn't in place at the time."
The board has drafted new rules to cover such situations. The proposed regulations are now being reviewed.
Midway Energy didn't follow its own guidelines when it began pumping high-pressure fluids underground Jan. 13 near Innisfail, Alta., in an attempt to release oil deposits.
"Midway did not conduct the fracturing operation in compliance with its own internal procedures," concluded the board's investigation.
The result was a geyser of oil, natural gas, process water and fracking fluids from an adjacent well owned by Wild Stream Exploration. The mixture tainted the field and left a thin film on nearby trees.
The board found both wells were targeting the same formation about 1,800 metres underground.
Midway's internal guidelines say its drill hole should have been at least 135 metres from any other well. At their closest point, the two well bores were 129 metres apart.
As a result, pressure from the Midway well blew fluids up the Wild Stream bore hole.
A passerby spotted the discharge and notified the board. Alberta Health Services, Alberta Environment, Alberta Emergency Management and the County of Red Deer all responded.
The spill affected 4.5 hectares and required the removal of just over 1,000 tonnes of soil and snow. The board concluded ground water wasn't affected.
Shortly afterwards, the board issued a bulletin to industry that said drillers would need to understand their surroundings before beginning to frack. A draft directive was issued last week.
"As soon as this draft directive is no longer draft and the rules come into force, it would be enforceable," said Barter.
Midway Energy has since been bought out by Whitecap Resources (TSX:WCP).
— By Bob Weber in Edmonton