The proposal drew an immediate outcry:  Wealthy environmentalists have vacation homes in the Methow. A Methow Headwaters Protection Act was introduced by Sens. Patty Murray and Maria Cantwell, D-Wash., to put 340,000 acres of federal land the upper valley off limits to mineral entry.

U.S. Agriculture Secretary Tom Vilsack, boss of the Forest Service, threw in with the opponents on Thursday.

“I support (the proposal) and believe a mineral withdrawal is the best path toward mitigating any impacts to the ecological, cultural and economic significance of the Methow Valley to the surrounding communities,”  Vilsack told the senators in a letter.

The Forest Service has begun what it calls a withdrawal application, an identification of the land and justification for blocking mining, that will take at least a year to complete.

The Methow River, at the east end of the North Cascades Highway,  boasts some of Washington’s cleanest water, and is about as far as salmon can swim upstream off the main Columbia River and its tributaries.

Sen. Cantwell, responding to Vilsack’s letter, said:  “The Methow Valley is too significant to allow mining exploration that threatens our clean water.  I’m glad to see the department working on the withdrawal application and I will stay focused on ensuring the process moves quickly to protect this pristine region.”

(A prominent opponent of the drilling, proposed by British Columbia-based Blue River Resources, held a fundraiser for Cantwell at his digs near Mazama when the senator last ran for reelection.)

Sen. Murray pledged to keep working on “all avenues to protect the ongoing salmon recovery efforts and the region’s outdoor economy.”

The Methow Valley is a bit like the Ketchum-Hailey-Sun Valley area in Idaho, a progressive, “green” redoubt in a conservative, pro-development corner of its state.

It is a fabled winter cross-country ski destination, boasts the state’s largest mule deer herd, the state’s highest road (above Harts Pass), and is summer takeoff point to such hiking destinations as Twisp Pass and Goat Peak.  (The 7,001′ summit of Goat Peak is the highest spot where a rattlesnake has been spotted in the North Cascades.)

“My business is one of the more than 135 businesses in the valley that has supported efforts to keep our valley special and the local economy strong,” said Sam Lucy, owner of the Bluebird Game Farms.

Developers’ big dreams come a cropper in the valley.

The Aspen Skiing Corp. once proposed the Methow for a major destination ski resort.  Opponents stopped it, along with subsequent smaller versions.

Several of Blue River Resources’ most adamant opponents now own land where Aspen Skiing Corp. was once going to build its golf course.