Environmentalists are as unhappy as timber interests over the state Natural Resource Board’s decision to set the 10-year sustainable harvest for state timber trust lands at an annual average of 597 million board feet.

After Tuesday’s decision, North Olympic Timber Action Committee Executive Director Carol Johnson said she was disappointed the harvest level wasn’t set at 636 million board feet.

Now the Washington Environmental Council is reviewing the decision — and deciding whether to challenge it in court, said spokeswoman Becky Kelly.

Environmentalists feel 597 million board feet is still too high.

“It’s not sustainable,” she said.

Kelly said the Washington Environmental Council has a number of concerns with the harvest level decision, some possibly shared with timber interests, such as its sustainability.