The New Jersey Agriculture Department questioned the validity of a new federal study showing ground water under southern New Jersey farms is contaminated with higher levels of nitrate than anywhere else in the nation.
Ferdows Ali, a water specialist at the Agriculture Department, said the study was not conducted over a long enough time or wide enough area for such sweeping conclusions to be drawn.
He added that the study area covered only 10 percent of southern New Jersey and that agricultural monitoring involved only 15 wells tested in 1996.
"It is alarming to know there are some hot spots," Ali said. "But before generalizations are made, one has to study other areas."
The U.S. Geological Survey (USGS), found nitrate levels in shallow monitoring wells under southern New Jersey farms were the highest of 47 studies nationwide.
Unless farming practices change, nitrate is expected to contaminate drinking-water wells throughout the region over the next 50 years, according to the report.
"We believe the information we are presenting is accurate, and we think our interpretation of the information is statistically sound," said Eric Evenson, chief of the USGS New Jersey District.
The New Jersey Farm Bureau, an industry group, also questioned the findings Tuesday.
Bill Wolfe, policy director for the Sierra Clubs New Jersey chapter, said farming interests are trying to discredit the USGS findings because they are nervous they will be held liable for polluting an irreplaceable public resource.
High nitrate levels in drinking water can cause a form of anemia in pregnant women and babies, commonly called blue-baby syndrome. In coastal bays, excess nitrate can lead to harmful algae blooms, oxygen depletion and fish kills.
Nitrate in water also creates radioactive water by releasing naturally occurring radium from its natural bonds in the soil, according to a prior USGS study.