Sunday, August 10, 2014

Alaskan Cripple Creek shows plenty of color



Mining at the Cripple Creek mine covered about one square mile beneath and south-southeast of the town of Ester, Alaska. 


By Rob Carrigan, robcarrigan1@gmail.com

As it turns out, there are about 15 different streams in Alaska that are called 'Cripple Creek,' but as usual, the one most remembered — is the one where the gold was.
That one, first recorded in 1904, was very rich and flows down Chena Ridge into the Chena River, not far from Fairbanks.
The mining at the Cripple Creek mine covered about one square mile beneath and south-southeast of the town of Ester, Alaska.
The Cripple Creek pay channel was described as an ancient channel of Ester Creek which branched from the present course of Ester Creek roughtly opposite the mouth of Ready Bullion Creek.
"The auriferous gravels at Cripple Creek are very deep; they are overlain by several hundred feet of barren gravel and reworked loess or so-called muck that washed into valley from the surrounding hillsides. Beds of clay several feet thick were found at various elevations. Subsequent to deposition of the gravels there had been considerable faulting and tilting that has resulted in grades of 5 to 8 percent on the surface of the gravel as well as the bedrock The gravels vary in thickness from 60 to 167 feet; these are overlain by muck that varied in thickness from 100 to 187 feet. 
There was almost certainly deep, early drift mining on Cripple Creek in the early days of mining in the Fairbanks district but it was probably attributed to Ester Creek mine (FB034) or simply Ester," according to J.C.. Boswell, in his book "History of Alaskan operations of United States Smelting, Refining and Mining Company published by Mineral Industry Research Laboratory, University of Alaska, (1979).
United States Smelting, Refining, and Mining Company (U.S.S.R. and M) consolidated most of the property in Ester and Cripple Creeks in 1930, and this was one of the major centers of placer mining in the Ester area until the dredges stopped mining in the late 1960s. U.S.S.R. and M. began extensive churn drilling on the Cripple Creek pay channel in 1933; they began stripping muck in May 1935 and barren gravel in September 1939. Dredge No. 10 started digging in August 1940 and, except for a closure during World War II, it continued on working Cripple Creek until 1964. It was the last dredge U.S.S.R. and M. operated in the Fairbanks area and remains in its pond south of Ester, says Joylon Ralph, founder of Minedat.org.
One interesting aspect about the Cripple Creek, Alaska, mining operation was the role that water and hydraulic mining played.
The Chena Pump House is emblematic of the engineering expertise and expense expended to make hydraulic mining work in the region.
Around 1930, the chief engineer of the company (Fairbanks Exploration Company, a subsidiary of U.S.S.R. and M) derived a scheme of mining Cripple Creek by pumping water from the Chena River up over Chena Ridge.
"This provided enough pressure to operate the hydraulic giants which were used to strip the overburden. The pump was completed and began operation in 1933," according to the Pump House application to National Historic Record.
"Inside the building were ten, 14", double suction centrifugal pumps rated at 6000 gallons per minute against 220 foot head and direct connected 400 hp electric motors. These pumps were mounted in a series, with tow each unit, through three, 26" pipelines against a total head of 440 feet. Water was delivered from there through a three mile ditch to the site of the mining operations where it was used for stripping and thawing and for make-up water for the dredge pond when needed."
According to Register application, The Fairbanks Exploration Company ceased operation about 1958, and the building set empty, surrounded by junk pipe, and rusting equipment, overgrown with willows,   until 1978. It was reconstructed by its present owners as a restaurant and bar.
"The basic structure of the building remains unchanged, and the original corrugated siding has been retained. On the interior, the main portion of the original building remains as an unbroken space housing the restaurant and bar,"  according to 1982 Register application that was subsequently approved.
In describing the significance of mining in this location, the Register information goes on:
"The dredging of the Cripple Creek drainage was one of the most complex undertaken by the company. The time, effort, and equipment put into developing the prospect suggest that it was probably one of the richest area mined. The huge Dredge No. 10, constructed for the project in 1940 was the largest ever operated by the company, and the walking dragline, specially constructed for the stripping of barren gravels unique to the area, was the largest in North America at the time of its construction."


















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