The U.S. Geological Survey, after an eight-year study, found that 33 percent of the wells tested between 1989 and 1996 had unsafe levels of radium. The USGS analysis, which was released in the past month but not publicized, found unsafe levels of radium in drinking water from wells in these counties: Camden, Gloucester, Atlantic, Salem, Cumberland and Ocean. Other areas of New Jersey are being tested.
USGS officials said that unsafe radium levels were found in 65 percent of the water supplies tested in the more heavily developed areas of those six counties.
Radium is a known cause of bone and nasal cancers. It is especially dangerous to children who have developing bone tissue. When a person ingests radium, the body interprets the radioactive element as calcium and deposits it in bones, according to the USGS. "Because it accumulates in the body, radium is considered to pose a greater cancer risk than most other radioactive elements," the USGS analysis said.
People with private wells in the counties with polluted water supplies should have their water tested, say officials of the New Jersey Department of Environmental Protection. If radium levels are found to be too high, the residents should either hook into a municipal water supply, buy water-treatment equipment, or buy bottled water for drinking and cooking, the DEP said.
Eric J. Evenson, district chief for the USGS in New Jersey, said, "The issues associated with radium in drinking water are significant public health concerns. It is an issue that warrants public health attention. It is of direct concern for individual well owners."
Philip Hopke, a chemist who does radiation studies for the National Academy of Sciences, said that water with radium levels such as those identified in New Jersey should be treated before being consumed.
Hopke, a chemistry professor at Clarkson University in Potsdam, N.Y., said current safety standards for drinking water are appropriate.
"It's not overly cautious," he said. "In fact, the more we tend to learn about [ radiation ] activity, the more we tend to" make the standards tougher.
Beginning in the mid-1980s, some South Jersey townships discovered that their groundwater was contaminated with radium; those findings led to the eight-year USGS study. The results of that study show for the first time that the radium problem is widespread throughout most of South Jersey.
Most of Southeastern Pennsylvania draws its drinking water from rivers and not aquifers.
The study also found that the radium, which occurs naturally, gets into the water because of pollution from fertilizer and lime used on residential and agricultural land. When chemicals from the fertilizers seep into the aquifer, they help move radium deposits into the water, according to the USGS.
The radium-tainted water is in the Kirkwood-Cohansey aquifer, a groundwater supply that contains 17 trillion gallons of water under 3,000 square miles of southern and central New Jersey. According to the New Jersey DEP, about 200,000 private wells draw water from the Kirkwood-Cohansey aquifer.
DEP estimates that about 500,000 people drink water from those wells.
In addition to the private wells, some municipal water authorities in South Jersey draw water from the Kirkwood-Cohansey aquifer. They "mix" the aquifer water with water from other sources to lower the percentage of radium in drinking water.
Federal officials point out that such "mixing" does not eliminate radium from the water, but does bring it within acceptable EPA standards.
The USGS found that the radium content in the Kirkwood-Cohansey aquifer ranged from 0 to 30.3 picocuries per liter of water, with the highest levels in Cumberland County.
The U.S. Environmental Protection Agency (EPA) has set a limit of 5 picocuries per liter of water as the maximum amount of radium allowed in drinking water. In interviews, EPA officials in Washington said no amount of radium is safe to ingest and that a limit of 5 was set because of "economic considerations."
"We set 5 for practical reasons and because of the cost of treatment," said David Huber, the EPA's national radium expert. "Our goal is 0," he said.
The EPA says that at 5 picocuries, one in 10,000 adults who drink the water over their lifetime risks fatal cancer. As the amount of radium increases, so does the risk factor, officials said.
Using those numbers, federal officials estimate that more than 50 adults in South Jersey are likely to develop fatal cancer as a result of longterm drinking of water from the Kirkwood-Cohansey aquifer. The EPA is doing studies on the effects of radium on children.
The USGS has done similar water sampling in states across the country. It has found groundwater radium problems in Illinois and the Upper Midwest and reports it is beginning to find radium problems with groundwater in Maryland.
The findings in Illinois were too recent for scientists to do epidemiology studies about the health effects on people who drank the water.
Radium became an issue in New Jersey in 1989 when unsafe levels were first found in the Kirkwood-Cohansey aquifer. DEP officials said blending the water containing radium with clean water was an acceptable way to treat the problem.
Many residents and some town officials said they felt blending did not solve the problem because it still left radium in their drinking water. DEP said that the radium in blended water was at a level low enough to meet federal environmental standards.
State and federal officials point out that there is no simple solution to the problem.
Until the mid-1980s, many South Jersey towns drew their drinking water from a deep and shale-protected aquifer known as the Potomac-Raritan-Magothy. But, because of rapid and large-scale land development, too much water was being drawn from that source, causing salt water to move up from the ocean, threatening the purity of the aquifer's water.
In the mid-1980s, state officials cut back access to the Potomac-Raritan water, forcing many towns to find other sources. Some towns, especially in Camden County, opted to pipe in water from out of state.
Many other towns drilled into the Kirkwood-Cohansey aquifer, a larger pool of groundwater that lies much closer to the surface. Because it lies so close to the surface, any chemicals or pollutants on the ground can easily find their way into the underground water supply, officials said. Since the early 1990s, officials have found unsafe levels of mercury, nitrates and, in some places, radium.
The Kirkwood-Cohansey aquifer is an underground reservoir beneath two-thirds of the New Jersey Coastal plain. It consists of two geological formations, the Cohansey Sand and the Kirkwood formation. These are joined with the Bridgeton formation, which overlies portions of the aquifer.
The USGS studied 170 private, public and observation wells in the aquifer, looking for radium 226 and 228, the most commonly found radiums. Later, the scientists discovered radium 224, a lesser-known, but equally dangerous, radium. They then began a new study to learn how much radium 224 is in the aquifer. That study is expected to be completed later this year.
The radium discoveries come four months after the state DEP warned all private well owners using the Kirkwood-Cohansey aquifer to test for unsafe levels of mercury in their water. Mercury is a known cause of kidney failures and birth defects and was found in unsafe levels throughout the Kirkwood-Cohansey aquifer by the USGS in 1997.
The USGS mercury study tested 34 sites in Atlantic, Burlington, Camden, Cumberland, Gloucester, Ocean and Salem Counties. Thirty-two of the sites yielded water that contained mercury in concentrations exceeding the safe health standard of two parts per billion, according to a 1997 report.
Out of 2,239 wells tested, 265 -- about 12 percent -- violated safe health standards. Mercury contamination is the result of pollution from landfills, military operations, cemeteries, industrial and commercial businesses, and mercurial pesticides.
The DEP, in its warning to well owners, said that mercury contamination in New Jersey has been reported only for the Kirkwood-Cohansey aquifer.
Anthony S. Navoy, assistant district chief of USGS, said, "The Cohansey aquifer is a dilemma. It's the easiest to get water out of, but it is also the easiest to contaminate."
Click here for a map of tainted wells
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