The U.S. Environmental Protection Agency (EPA) has announced a proposed plan to clean up the ground water at the NL Industries Inc. Superfund site in Pedricktown, N.J., that is contaminated with heavy metals, including lead and cadmium. The 44-acre site is a former lead smelting facility where lead from old automotive batteries were drained of sulfuric acid, crushed and processed for lead recovery. The Delaware River is approximately 1 1/2 miles from the site. The Cape May aquifer underlies the site, and serves as a source of drinking water and water for crop irrigation. Some area homes are connected to a municipal water supply that provides a safe source of drinking water. Other residents in the area receive their drinking water from private wells, which are monitored to ensure that they meet drinking water standards.

Lead is a toxic metal that can cause damage to a child’s ability to learn and a range of health problems in adults. Even at low levels, lead in children can cause I.Q. deficiencies, reading and learning disabilities, impaired hearing, reduced attention spans, hyperactivity and other behavior problems. Lead exposure also can cause health problems in pregnant women, and harm fetuses. Excessive exposure to cadmium can cause cancer.

EPA has proposed an approach to clean up the contaminated ground water by injecting an non-hazardous additive into the ground water to absorb the metals instead of using the more traditional method of pumping the ground water to the surface and treating it to remove contaminants. EPA held a public meeting on July 7 to explain the proposed plan, and will accept comments until July 21, 2011.  

“Making sure that people have a safe source of drinking water is one of EPA’s top priorities,” said EPA Regional Administrator Judith A. Enck. “The treatment of contaminated ground water at the NL Industries site will keep the contamination from polluting drinking water supplies and causing more damage to this important natural resource. EPA encourages public input on the proposed plan.”

The NL Industries site was added to the Superfund list of the most contaminated hazardous waste sites in 1983. Because of the nature and complexity of the contamination at the site, EPA divided the investigation and cleanup into multiple phases. Previously, EPA removed contaminated waste, soil, sediment, piles of lead, debris and standing water; demolished contaminated buildings on the site; secured other areas; and conducted sampling and monitoring activities. Cleanup work at the site has been conducted by both EPA and the party responsible for the contamination, with EPA oversight.

EPA had originally planned to pump the contaminated ground water to the surface, treat it, and discharge the treated ground water into the Delaware River. This type of treatment no longer is needed because pollutant levels in the ground water have gone down significantly as the sources of the contamination have been removed. EPA conducted a review of newer treatment methods, and now is proposing to inject a non-hazardous additive into the ground water that will absorb metal compounds such as lead and cadmium and remove the dissolved contaminants from the ground water. EPA will conduct a study to determine the type and quantity of the additive to be used. Sampling and further study also will be conducted to ensure the effectiveness of the remedy.

EPA is requesting public comments on the proposed plan, which will be accepted until July 21, 2011.