Findings & Recommendations for the Remediation of Historic Pesticide Contamination - Final Report March 1999
Table of Contents

I. Introduction

      Farmers, orchardists, homeowners, turf growers, local governments and others have used a wide variety of pesticides over the last 100 years in an effort to control pests and increase crop yield. Many pesticides were used in limited circumstances, others became widely used, and some became the "pesticide of choice" for entire crops or industries. Some of these pesticides are persistent in the environment, and thus may be present in the soil long after they have been applied. As a result, residues of a number of pesticides (including arsenical pesticides, DDT and dieldrin) can be found in soils at levels that may pose a human health risk. The New Jersey Department of Environmental Protection ("the Department") estimates that up to 5 percent of the state’s acreage may be impacted by the historical use of arsenical pesticides alone. The primary concern with historical pesticide residues is human health risk from inadvertent ingestion of contaminated soil, particularly by children.

      As more and more agricultural land is developed, developers, municipal officials, homebuyers and others are becoming increasingly aware of the possible presence of pesticide residues in soils. Some municipalities now require environmental assessments of land as part of their site approval process. Banking institutions take environmental risk factors into consideration in their lending decisions. Developers and builders sample soil more frequently to determine whether or not to purchase land or how to develop land they already own. Homebuyers are also considering pesticide residues along with a myriad of other environmental factors such as indoor air radon levels, the presence of lead paint in the home, and the quality of potable water. The presence of pesticide residues is also a consideration in non-residential property uses including day care centers, schools, parks and general commercial and municipal usage.

A. Creation of the Task Force

      Increased numbers of people have been requesting technical and remedial advice from the Department. Numerous questions regarding historic pesticide impacts and the appropriate course of action have been raised. At the request of Department Commissioner Robert Shinn, an informal, interagency task force started meeting in July 1996 to address these questions. It was determined that additional expertise and a more formal structure would facilitate a thorough review of these questions. Commissioner Shinn then memorialized the Historic Pesticide Contamination Task Force ("the Task Force") by Administrative Order 1997-09 (April 1997).

      The mission of the Task Force was to develop strategies and recommend implementation plans that will assist the Department in establishing and achieving an environmental course of action for sites with contamination due to historical use of certain pesticides. Nine task force members were chosen with appropriate backgrounds from the stakeholder groups listed below. (See Addendum 1).

      The Task Force developed a number of specific goals. These included:

• Evaluation of potential adverse human health effects and environmental impacts from historic pesticide contamination.
  
  
• Identification of technically and economically viable alternatives and strategies to limit human and environmental exposure to contamination from historic pesticide use at sites that have been developed and that will be developed in the future.
  
  
• Identification of any barriers to the implementation of these options including cultural, institutional and legal barriers, and recommendations regarding removal of those barriers.

      The Task Force met under the direction of Richard J. Gimello, Assistant Commissioner for the Department’s Site Remediation Program. Other individuals who attended meetings and served in an advisory role were representatives from various state agencies (exofficio members) and members of the public. Representatives from the following groups served as exofficio members of the Task Force as needed:

      In addition, the Department has comments made by Task Force members on file regarding historic pesticide contamination and the findings and recommendations contained in this report.

B. Selection of the Pesticides of Concern

      In early 1996, a developer approached the Department with soil sampling data that showed that homes in two Burlington County developments were built on soil containing pesticide residues with concentrations of arsenic, DDT and its metabolites, and dieldrin above the Department’s residential soil cleanup criteria. About the same time, the Department was conducting an investigation of a Superfund site in Monmouth County and identified several areas with similar levels of arsenic, first thought to be related to the Superfund site. Further analysis indicated a significant contribution of arsenic contamination due to pesticides used in the former apple orchards adjacent to the site (Barringer, et al. 1998). Investigations were complicated by the fact that some soils (glauconitic soils) in the region of the sites being investigated contained elevated concentrations of naturally-occurring arsenic (Barringer, et al. 1998). This information, along with additional analytical data from other sites, led the Task Force to initially focus on these pesticides as the pesticides of concern.

      After additional discussion, these pesticides were kept as the pesticides of concern based on several factors including their extensive agricultural use over a number of years in New Jersey, their persistence in the environment and the fact that they have been detected at levels that exceed the Department’s residential soil cleanup criteria at various sites.

      The amount of analytical data upon which this report is based is very limited. The Task Force and the Department decided that it was important to proceed with this report and to develop recommendations to address the health risks associated with historic pesticide contamination to assist developers and others to make appropriate decisions concerning properties with pesticide residues. The Task Force decided it could meet its goals by focusing on select pesticides of concern.

      The chemical analysis for the organochlorine pesticides of concern (DDT and its metabolites, aldrin and dieldrin) is accomplished with what is referred to as a pesticide scan. The pesticide scan (USEPA method SW 846-8081A) detects twenty-one pesticides including the pesticides noted above. A list of all of the compounds detected by this analytical method is provided in Addendum 2. It is possible that concentrations of other commonly used pesticides, such as chlordane, BHC, endrin and others will be detected in soil when additional properties are investigated. Therefore, pesticide use and human health risk information for these additional pesticides identified by the pesticide scan are provided in Addendum 3 of this report.

      The guidance and recommendations contained in this report are intended to be applicable to the historical pesticide contamination resulting from routine agricultural applications. Because site conditions will vary, individual sites must be evaluated and remediated on a site specific basis.