The directive was contained in an environmental protection order to Coal Valley Resources and Sherritt International (TSX:S).
The order comes almost three weeks after an earth berm broke at the Obed Mountain mine near Hinton, allowing coal waste to spill into two creeks that feed the Athabasca River.
Alberta Environment spokeswoman Jessica Potter said the companies have been taking steps to remediate the spill.
Potter said the environmental protection order formalizes the cleanup and gives timelines and deadlines.
"It offers us an opportunity to clearly outline expectations," she said. "It's a tool to ensure action is taken."
Potter said no decision has been made on whether environmental charges will be laid.
"We are investigating and, if we feel environmental laws have been broken, it is something we can consider doing."
The spill on Oct. 31 sent clay, mud, shale and coal particles into Apetowun and Plante creeks.
An Environment Canada database says the spill contained damaging compounds such as arsenic, mercury, cadmium, lead and manganese.
The pollutants have been found to exceed safety levels as far as 40 kilometres downstream of the spill.
The province has advised all downstream communities not to draw water from the river while the slurry floats by.
Farmers have been advised to not let livestock drink from the river.
The spill is now within 180 kilometres from Fort McMurray, but has been dissipating as it travels.
NDP critic Rachel Notley said a three-week lag to get an environmental protection order in place is not good enough. She suggested the government has not been forthcoming on the types of pollutants.
"It appears after they found out there was arsenic in the water, it still took them 18 days to disclose that to the people of Alberta," said Notley.
"Albertans simply cannot count on this government to keep our air, our land and our water safe."
The order requires Sherritt and Coal Valley to put together plans for recovering the solids, mitigating effects on wildlife and managing mine waste and waste water. The companies must also develop a remediation strategy and a way to assess short- and long-term impacts.
Sherritt must also take steps to prevent waste-water solids in the creeks from entering the Athabasca River and develop and implement water sampling and monitoring.
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