groundwater

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The question I have deals with Florida's supply of groundwater. Flordia wants to collect rainwater and deposit it into the ground. If Florida gets the approval to do this wouldn't the lakc of ater on the surface lead to drought in the upperwestern part of Florida? With the rain water being collected the air could not get saturated.

April 13, 2001 Florida, Low on Drinking Water, Asks E.P.A. to Waive Safety Rule By DOUGLAS JEHL

MIAMI, April 12" In a bid to head off drinking-water shortages, Florida is nearing approval of a plan that would allow billions of gallons of untreated, partly contaminated water to be injected deep into the ground in what would serve as subterranean water banks. Aides to Gov. Jeb Bush say that the approach, which would involve capturing rain water before it flows to the sea, would save the state hundreds of millions of dollars in treatment costs, and that extensive precautions would be taken to avoid any danger to human health. With the aquifers that are Florida's main source of fresh water already at dangerously low levels, the aides say the severity of the problem demands fresh solutions. State officials say that bacteria in the tainted water could not survive underground or at least that the contamination would not spread through ground water. Opponents say that studies are not conclusive and that the plan, which goes far beyond anything tried in the United States poses far too great a danger, particularly for private wells. To proceed with the plan, state officials have asked the Environmental Protection Agency for a waiver of the federal rules that, under the Safe Drinking Water Act, require that any water pumped into the ground be treated first to meet drinking-water standards. The governor included such an appeal in a January letter to his brother President Bush. The agency has not said whether it will approve the request. In his letter, Governor Bush noted that Florida's plan would require that the stored water be treated before it was made available for humans and he asked that the agency demonstrate "a willingness to abandon conventional processes as long as the environmental results are achieved." "E.P.A's insistence that naturally occurring surface water should be treated to `drinking water standards' prior to being placed underground," the letter continued, "only to be retreated again to the same standard when pumped out of the ground for use, is nonsensical." Among the issues in dispute are whether the untreated water might contaminate private wells, where drinking water is typically not treated, and whether the high-pressure injection process might disturb the underground geology and affect the purity of the existing aquifers. "This is something that really has not been studied yet with respect to the injection of untreated surface water," said John Vecchioli, who recently retired as the district director in Florida of the United States Geological Service. "I think the state could be opening the door to a lot of problems." To a limited extent, other states, like Arizona and Utah, have begun to use the underground water-banking procedure, which is known as aquifer storage and recovery. But they have followed the federal guidelines and pumped only treated water into the ground. With hundreds of wells planned for South Florida and, potentially, in other parts of the state, Florida's effort would be a departure in scope and substance, as the State Senate made clear on Thursday in approving a measure that would specifically authorize injection of untreated water. The House is expected to follow suit, with Governor Bush prepared to sign the measure into law. The plan, designed to capture as much as 1.7 billion gallons of water a day that would otherwise flow into the ocean in South Florida alone, would be the latest of several unusual approaches by Florida to the problem of adequate fresh water. A plan nearing final approval by state regulators calls for construction in the Tampa Bay area of a seawater- desalination plant that would be the second-largest such plant in the world. "Clearly, we're at the point where demand is creeping up and supply is not, and that's why we're beginning now to look at plans that will make sure that we look at plentiful supplies 20 years from now," David Struhs, who heads Florida's Department of Environmental Protection, said in a telephone interview today. The state is in the midst of a drought that is the worst in 50 years. With its population projected to grow to 20 million from 15 million over the next 20 years, forecasts say that without new sources of supply Florida by 2020 would face a water deficit of as much as 30 percent. In large part, the decision to turn to aquifer storage and recovery is a product of the $7.8 billion state-federal plan to restore the Everglades, the vast natural ecosystem that is greatly in need of new supplies of fresh water. The plan calls for construction of 333 wells that would be used to store rain runoff, with the stored water to be pumped up during the dry season to flow across the Everglades. Water users in South Florida would also benefit from that plan, because the new flows would help to recharge natural aquifers, adding as much as much as 20 percent to available supplies of drinking water. Still, in a recent report, the National Academy of Sciences warned that many questions remained about the potential effects of water-banking, whether or not the water injected into the ground was treated first. And across the state, environmentalists and scientists have raised concerns that the injection of untreated water in particular could foul existing underground supplies. "This is a resource that we shouldn't mess up," said Dr. Harold R. Wanless, chairman of the department of geological sciences at the University of Miami, who called the state's plan "idiocy." Among the substances that would be introduced into ground water under the Florida plan is fecal coliform bacteria, which is commonly found in agricultural water runoff but could pose health hazards if ingested. Some studies cited by the state have suggested that the bacteria would die underground, and the state's plan calls for monitoring to ensure that. The plan also calls for tests to detect toxic substances, which would not be permitted in any water to be injected underground. It also envisions that the injected water would be kept separate from the Floridian and Biscayne aquifers, the state's main sources of water, because fresh water tends not to mingle with the saltier ground water in the aquifers. If drinking water supplies are fouled, existing treatment would purify it, state officials say. And private wells would be monitored to guard against contamination. Critics, including John H. Hankison Jr., who served under President Bill Clinton as the E.P.A.'s administrator for Region 4, which includes Florida, have expressed skepticism about claims that the bacteria would die underground. They have also suggested that the high-pressure injection process might disrupt the subterranean geology in a way that could cause unwanted mixing between fresh-water supplies in some aquifers and the brackish water that has begun to intrude into other aquifers near the Gulf of Mexico and Atlantic coasts. A safer, more conventional means of storing untreated water would be above the ground, in reservoirs or other surface impoundments. But Florida has shied from that approach because the state's generally hot weather would cause much of the water to be lost to evaporation. Under the current Everglades plan, about $1.7 billion of the total $7.8 billion cost is set aside for construction and maintenance of the underground water banks, and of that, about $700 million is set aside for water treatment. State officials say the latter cost, which would be split equally between the state and federal governments, could be reduced by $500 million if the pre-storage treatment is not carried out.



-- Kimberly Corkran (corkran@oswego.edu), April 19, 2001


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