International Dredging Review

International Dredging Review

When the Colorado Historical Society awarded a $225000 grant this year for restoring the Snowstorm dredge in Fairplay it was the peak of seven years of effort by a group of local people interested in preserving their mining heritage.

Gary Higgins is the guiding force for the effort. He realized that this was the last intact gold dredge in the state and set about the task of getting the support and funding for restoring it. In the process he became an expert on the design equipment operation and history of the dredge and he has envisioned the finished display including how to provide wheelchair access for viewing most of the equipment.

Fairplay is approximately the geographical center of the State of Colorado in a mountain valley that is rich in placer gold deposits. It was extensively mined starting in the late 1800’s and the tailings piles from the dredging operations are still there stretching for miles in some cases. At Breckinridge 30 miles north the tailings have been used as aggregate for construction and have almost disappeared. The historical society there is attempting to preserve some of the tailings as historical landmarks.

The dredge is at Snowstorm Sand and Gravel LLC a placer gold deposit about two miles north of Fairplay. It is at an elevation of about 11500 feet and is owned by a group of Dutch investors. Because the earth is porous after the dredge shut down for the last time in the mid-1970’s the water drained out of the pond and the dredge settled to the bottom.

Built in 1939 the all-steel dredge worked the Snowstorm placer deposit from 1941 until 1948 or 1949. It was retrofitted and worked again in the 1970’s.

The dredge is a Bodinson gold washing plant fed by a dragline on shore. The Page dragline crane was said to be the largest in the country at the time said Higgins. The huge dredge 86 feet by 42 feet has remained intact with the equipment protected inside. It is on private land which has saved it from vandals though the owners have removed equipment over the years for other purposes.

March 5 was a clear day with a brilliant blue sky. Snow capped peaks surrounded the valley as Higgins led a small tour of the dredge. After checking in with the caretaker and manager of the operation the group proceeded over a hill to the dredge.

An 18 x 23-foot hopper dominates the front of the dredge and steel I-beams form a grizzly on top of the hopper to deflect the larger boulders. At the time of the retrofit the center I-beams were removed allowing more oversized material into the trommel.

The wheelhouse contains the four winches that positioned the dredge via anchors on the bank and other controls are located here also.

Higgins led the group down several flights of stairs to the riffle tables 1000 square feet on each side of the trommel enclosed in an expanded mesh cage that was locked to prevent pilferage. As the trommel turned the gold-bearing material dropped down and dozens of water jets washed it over the riffles where the gold settled out into an underlying layer of burlap. The 65-foot-long eight-foot diameter trommel is graduated with the finer holes at the bottom. The finest material was washed by hand on a table called a “long tom.”

Higgins pointed out two 14-foot sand wheels that removed sand from the sides of the washing operation and placed it directly onto the stacker.

In the 1970’s large holes were made in the bottom of the trommel to take out the oversize ahead of the stacker.

The stacker is 135 feet long with a conveyor belt running up the center and a walkway all the way to the top (see cover). Movable bars allowed large rocks up the conveyor and prevented them from rolling back down.

Other features of the dredge:
• electrically operated by GE motors at 4000 volts stepped down to 440;

• in the hull under the riffle tables are mercury boil pots for capturing the gold fines that are not caught in the riffles;

• a boiler in the hull on the starboard side drove steam heat through the pipes to keep the riffles from freezing;

• the intake pump is a 14-inch centrifugal pump from United Iron Works Oakland California powered by a GE engine.

Though it would seem that mercury would escape and contaminate the surrounding area all the mercury was accounted for by weight said Higgins.

The group needs at least $250000 more to move the dredge; $400000 to do it right said Higgins. He has solicited quotes from several movers and the procedure would be to remove the hopper stacker gantry and pilot house remove the trommel and separate the hull into three sections. The pontoons are 50 feet long by eight or ten feet wide by six feet deep placed athwart ships.

Moving the pieces a maximum of 50-feet wide would require permits from the Colorado Department of Transportation and arrangements to raise power lines along the way.

There is no danger of pollution during the move Higgins said. There is fuel in the storage tanks but it has been tested and is not contaminated with any other substance.

The dredge will be installed at the end of historic South Park City 32 original buildings brought from other Colorado mining towns and restored to their original functions as a museum. The museum street is an extension of the actual main street of the town of Fairplay. The total moving distance would be about four miles ending with lowering the dredge down a slope to a shelf above Beaver Creek.

The project has widespread local support and the grant from the Historical Society is a tremendous validation of the project which should encourage individuals and organizations to donate matching funds to complete the project said Higgins. A silent auction fund raiser is planned for this year and the Park County Historical Society Dredge Project group will spend the coming months soliciting donations for the final push to bring the Snowstorm dredge home.