You don’t have to travel far out of Jackson proper to see one of the most unique historic mining features in the world – The Kennedy Tailing Wheels. If you haven’t seen them, I would recommend you do so. However, you will need to wait until the effort to save Wheel No. 1 is complete, as the area has been closed off to visitors for the time being for safety reasons. The wheel is listing and there is a good chance that it will fall and suffer irreparable damage if measures are not taken to stabilize it. Although Wheel No. 4 has been encased and is now safe from the elements, preservation of any remaining features of this piece of Amador history is a plus. You see, it took four of those wheels to move mine waste from the Kennedy to Indian Gulch and a dam to hold it in place.
The impetus for the waste relocation project was the result of environmental legislation passed by the State of California, the first laws of this type in the nation enacted to protect against pollution. The Kennedy, and other mines along the gold belt, were required to have a method to impound tailings in place no later than December 1, 1914. If they failed to meet the deadline, they would be subject to paying out large fines and a substantial cash settlement to farmers who sued the mines in response to their farmlands being contaminated by mine waste during a heavy rainy season. While other Mother Lode mines opted to build dams, and transport their waste via gravity flumes, or dumped it in nearby natural valleys and depressions, the Kennedy mine faced the challenge of lifting the tailings over the hill to Indian Gulch. They chose to facilitate this via an ancient engineering method - overshot wheels of the type that had been used in Central Asia and the Middle East for centuries.
Designed by engineer James Spears, construction of the Kennedy Tailing Wheels began in February 1913 and was completed by December when they were set into place. At the same time, the wheels were being constructed the flume that would carry the tailings was also being built but was not yet finished when the wheels were raised. The Amador Ledger of December 5, 1913 reported, “The plant for the storage of tailings is all finished as far as the carpenter work is concerned. The wheels, supplied with buckets for the lifting of the debris, are in place. There are four lifts. The motors for operating these lifts have not yet been received but they are expected here in a short time.” The motors soon arrived, and in mid-January 1914, the first wheel was started. The newspaper reported that “it proved all right, did the work mapped out for it in a manner that met all expectations.” The buckets lifted the tailings and deposited them in the flume 50-feet above. The three remaining wheels were not yet in operation, as they were waiting on the long belts that would operate them to be delivered from the east coast. It was expected that by February, all four wheels would be in motion and the tailings that were lifted by the first wheel would travel through the 2 percent grade flume delivering them to the next wheel several hundred feet distant.
Owners of the Kennedy Mine also recognized additional benefits from impounding the tailings. They estimated, at the lowest, the tailings carried away, in the slimes and sulphurets, at least one dollar per ton in gold. Based on recovery operations in Jackson Creek several miles west of Jackson, the gold in the tailings could be recovered through amalgamation or cyaniding. At that time, the Kennedy was crushing 500 tons of ore per day. If their estimates were correct, they would be able to recover nearly $200,000 of gold per year from the tailings that would be deposited behind the dam.
In March 1914, the flume was completed and all four wheels were in operation. Each wheel captured the tailings and raised them nearly 50 feet, driven by 15-horse power electric motors. The plan went off without any hitches or leaks along the course. The distance from where the first wheel captured the tailings to where they were deposited in Indian Gulch was nearly a ¼ mile distant. Although the tailings were being transported to Indian Gulch as planned, construction on the settling reservoirs and the dam that was to impound them had not yet began. For the time being the tailings were being dumped into the middle fork of Jackson Creek.
By the end of May, the tailing wheels were enclosed in their metal-sheeted buildings supported by iron framework and the operation was running under the direction of engineer George Wrigglesworth who had moved his employment to the Kennedy Mine from the Zeile Mine where he had worked for many years. The engineering plans for the dam were finished and on April 30th Colonel William Henry Heuer of the Corps of Engineers arrived in Jackson to inspect the plans and the dam site. A newspaper reported that his visit was not in his official capacity but rather to give an individual expert opinion on the subject.
The work at the Kennedy Mine was not going unnoticed by those outside of Amador County. In 1915, San Francisco was to host World’s Fair, The Panama-Pacific Exposition. The theme of the fair was “Honor the American Workman.” The Kennedy Mine, acknowledged as the deepest gold mine in the United States was to be recognized at the fair with the commissioning of a moving picture about the mine. The announcement of this recognition was given to the citizens of Amador in May, 1914 by Robert Kerr, Amador County’s Exposition Commissioner. The film was to be made by Harold J. McCurry who was the official photographer for the Exposition Commission. Yes, that same McCurry for whom McCurry’s camera shop in Sacramento is named. In addition to filming the Kennedy Mine, McCurry was assigned to take still photos of various landmarks and places of scenic beauty in Amador to be displayed at the Exposition. This writer found no further reference to McCurry’s visit to the county in the newspapers of the day and has no knowledge of whether or not that film was actually made. I defer to the Kennedy Mine Foundation for those interested on further information on the subject. However, the Kennedy Mine and other mines did exhibit samples of ore in the Palace of Mines and Metallurgy building.
While plans were underway to film the Kennedy Mine, workmen began excavation for the dam and settling ponds in Indian Gulch on June 18, 1914. The plan was for the dam to stand just about ½ mile north of Jackson proper. Prior to the onset of work on the permanent dam, a temporary earthen dam was built about 100 yards from where the concrete structure would sit. For the time being, a small ditch conveyed the tailings to the gulch that connected to the middle fork of Jackson Creek. The permanent dam, with its foundation set in bedrock, was planned to be 440 feet long and divided into eleven sections. For most of the structure, it was only necessary to excavate 6 feet below ground surface before hitting bedrock; however, at the center of the dam, in the trough of the valley, they would have to dig to about 20 feet. The dam’s sections were defined by 12 massive concrete pillars or buttresses that would set at right angles to the dam and provide the main support. The span from center to center of the buttresses would be 40 feet. Between, and resting on the buttresses, the wall of the dam would consist of 11 semi-circular arched walls of concrete, twelve inches thick and over 30 feet in height in some places. They were designed as free arches so that the majority of the pressure load on the structure would be carried by the buttresses. To prevent lateral movement, beams were run through the buttresses from end to end, terminating in a counterfort. A small 15-foot wide and 2-foot deep spillway would be installed at the west end of the dam. The engineers estimated that the dam would be able to stand the pressure of 21 tons per square foot and would be able to hold back five years’ worth of tailings, nearly 16,000 cubic feet, being produced by the 100-stamp mill at the Kennedy, as well as the water used to transport the tailings. There were no plans to separate the tailings from the water and it was thought that it would eventually disperse through seepage and evaporation.
Work on the dam began on June 10 with the Eastwood Construction Company in charge. Things slowed to a crawl in mid-July while the workmen waited for more lumber to arrive. Once work resumed, it continued steady into autumn with the number of men working on the project varying between 20 and 40. In mid-October, it was estimated that it would be completed within six weeks. Racing to meet the State mandated deadline of December 1st, construction moved at a furious pace, but in mid-November it came to a halt for several days when some of the concrete-mixing machinery broke down. All the workers were temporary laid off until parts were found and the machinery repaired. The men were back at work within a week and getting close to the finish line. By November 20, engineers were confident they would meet the deadline as they reduced the workforce to fifteen men. That day, the Amador Ledger reported “The Kennedy plant will be in complete operation before the time limit expires.” However, despite their confidence, work was not completed until a few days after the deadline when on December 4th the opening in the base of the dam was closed. Even with the late completion, the Kennedy owners were spared paying any fines and litigation compensation. In mid-December it was reported that the dam was in “full operation” and was doing its job as planned with no polluted water spilling into Jackson Creek. On December 17th, the pond was full of water, up to within 10 feet of the top of the dam. Within that short amount of time, a large lake had already formed, covering a portion of the .13 acres of the former Bright Ranch that was available to hold the tailings. Upon its completion, the dam site became quite an attraction for sightseers, most going out for a Sunday afternoon trek to view it.
In the end the cost of the tailing wheels, wheel houses, flume, and dam was nearly 3 times more than estimated during the planning phase of the project. When the project was finished, the Superintendent at the Kennedy Mine estimated that the 100-stamp mill was spewing out approximately 850 tons of tailings every day. In 1915, the California State Mineralogist’s Report described the operation thus: “Tailings from the mill [go] to hydraulic classifiers or spitz-kasten, where the coarse sands are eliminated. The overflow [goes] to the slimes plant where the slimes are distributed to sixty canvas tables, size 10’ x 12’. The washings from the canvas tables [go] to two bumping circular tables and one Gates concentrator. The overflow from these goes to eight additional canvas tables. Waste overflow joins the sands from the classifiers and flows by means of a launder (flume) 990 feet long, with a grade of 2 ½ feet per 100’ to the first tailings elevator (wheel). The diameter of the tailings wheel is 68 feet, with 176 buckets per elevator (buckets 18” x 8”) having life of 48 feet to each elevator. These elevators hand 500 tons of pulp (tailings) with a consistency of 7 to 1 (water to tailings). Sixty inches of water are used in excess of the slimes. The slimes from [the] launder flow to the first elevator, which elevates [the] pulp to the second launder that carries [the] pulp a distance of 75 feet to the second elevator wheel, where the pulp is elevated to launder 800 feet long, thence to the third elevator wheel, which raises it to [a] launder 160 feet long that conveys the tailings to the fourth elevator, where the pulp is raised to a flume 1,000 feet in length and flows to [the] storage reservoir. Here the tailings are impounded by the concrete dam 540 feet in length and 50 feet high.”
Next week…The End of an Era and Preservation Efforts
If you would like to contribute to the effort to save Wheel No. 1, contact the Kennedy Mine Foundation or send your donation to the KMF, P.O. Box 684, Jackson, California 95642.