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Show V 8 SALT FLAT NEWS, MAY 1975 by Richard N. Goldberger Note: This is the third in a series about the Bonneville Salt Flats and the problem of thirteen million tons of missing salt. ' "During this (the brine) concentration process , large quantities of salt are deposited on the primary pond floor and the result of this salt buildup is a limitation on the economic ' " a ten life of pond to about years. Thu excerpt was extracted from a report called Production Plan For Pond System V Division. " The report was At Kaiser Aluminum And Chemical Corpomtion-Bonnevill- e prepared in April, 1974 , by G.A. Longtid , a Kaiser engineer, for submission to the United States Geological Survey, divisidn of Mineral Classification Office in Salt Lake City. The purpose behind this report is Kaiser's intention to relocate their primary collecting ponds in 1979. The proposed new location is on federal lease land, thus federal compliance is required. -- Muriate of potash and mag-- , nesium chloride are produced at the Wendover plant by the solar mining process. The controlled release from the brine of various salts by precipitation and by transferring more concentrated brines to specific ponds to achieve additional precipitation of minerals is the basic principle behind a. solar mining operation. In this process, sodium chloride first precipitates out on the the present time, three ponds have been retired, the avenge lifespan of an evaporating pond being ten years. Each year the ponds, according to Mr. Lallman, general manager of the At- - Bonneville Division, collect six to seven inches of sodium chlo- ride (table salt). After ten yean, when approximately five feet of 'salt have accumulated, the primary pond must be retired and a new collecting pond built. floor of the pond. Next, the brine is transferred to a harvest- ing pond where sylvanite (Au,Ag)Te2 is allowed to precipitate from the now denser brine. This mineral is then loaded into trucks by a scraper and hauled to the mill, also located at the Wendover riant. By the method of flotation, muriate of potash is concentrated to 96.5 percent and then taken to a drier; for commercial sales.- The self-propell- ed - amount' of potash actually recovered is about 85 percent, the remaining percentage bring recycled back into the primary ponds in the form of a slurry. Thus there is no waste in this system. After the. brine has precipitated sylvanite, the next alt that releafed is carhallite is (KMgCl36H20). It is important that the brines be very carefully monitored; otherwise, the cap nallite will settle out in the harvest pond intended for sylvanite. If this happens, the production' of potash is limited, since carnal-- . lite has noplace in the flotation method of concentrating muriate of potash. When the solution is 35 carnallite, the brine is theptrans-ferire- d to another pond called the magnesium chloride holding pond. This solution is . transferred by truck to another pond that is lined ' to prevent loss of this product through leaching. Another reason for the lined ponds is to insure a constant grade of magnesium chloride for shipping purposes. The four steps of solar mining then are: 1 COLLECTION or HAR: VESTING 2T CONCENTRATION 3 SELECTIVE, PRECIPITATION & COLLECTION . , sub-surfa- ce 4 CONCENTRATION & DRYING Covering approximately 87,000 acres, Kriaers operation, at Wendover spans various jurisdictions in the area of land ownership. The ownership breakdown of the land covered by the ponds is as follows: acres owned by Kaiser 57,518 . 24,699.83 acres owned by the federal government and administered by the Bureau of Land ' Management anT the . Division of Mineral Classifica- tion of the United States Geological Survey 6,238.44 acres of lind owned by the State of Utah with the lease revenues going to edu-- ' cation. This land is called ' School Lands, which are ad ministered by the Divirion of State Lands of the State of o . . .Utah; Production figures of potash ate a closed secret, but the NEWS has learned that 90,000 tons would be a conservative figure on an average production year. Potash sells on the world market at over forty dollars a metric ton. Production figures for magnesium chloride and sodium chloride are not available,' but if six or seven inches a year are precipitated, we assume the figure is large. Incidentally, the Utah Salt Company, situated approximate- . ly a mile and a half east of the Bonneville operation produces 100,000 tons of sodium chloride from brine it buys from Kaiser. Compared to the thirteen mil-- ; lion tons of salt lost from the Salt Flats during the past fourteen years, this figure is not even a drop fa the' bucket, according1 source at' the to a Kaiser plant. Three, primary ponds collect the brine taken from the northern portion of the Salt Flats. The brine is pumped to these ponds, via canals that reach out for miles across the Flats. When the brine enters the primary: ponds, the percentage of sodium chloride. is sixteen percent, but. after the brine is transferred to the sylvanite pond, the percentage has dropped to twelve percent What has happened to that four percent of salt? It has set- tied on the bottom of the ponds . at a minimum rate of six inches a year. Every ten years the primary ponds are retired! In four yearn, the present three primary ponds will reach their holding quota of sodium chloride and pond V will go into operation. The United States Geological Survey, under the direction of Gordon Whitney and Bruno Alto, "engineers of the mineral classification branch, are preparing an environmental impact' analysis of the Kaiser request. This EIA will be completed in a month, according to Mr: Alto. The EIA must then go to Wash-- ' ington. for final approval, and, that phase should take another month, according to agency , - -- . sources Kaisers request to relocate their primary ponds must be held in salty abeyance until . Washington grants, approval of the EIA What the EIA will state is not known, although the NEWS has learned unofficially that -- approval will be given to Kaiser to relocate these ponds. ' How' much salt is accumulated in a primary pond before it goes "into retirement? That, is a thirteen million ton question.. well-plac- ed . . . . . . d)3QSG Vol. No.1 1 $5.00 V These copies are extremely rare Selected back issues are available : for$1.00each . fi r!SIl3&"Wff&tS Aerial view of Kaiser's evaporating ponds. ' . 9 |