Vulnerability Assessment of Missouri Drinking Water Supplies to Atrazine Contamination--Phase II

Background

The Federal Safe Drinking Water Act requires that each public water supply be routinely monitored for specific chemicals, including atrazine. Tests show that atrazine is present in drinking water in Missouri. To better understand why atrazine is found in certain drinking water supplies, an investigation of the potential sources of atrazine in Missouri is required.

Objective

Collect, evaluate and document data related to atrazine use, storage, manufacture or transport in Missouri, and determine the proximity of these activities to public water sources.

Methods

The methods and information are based on those developed in the project Vulnerability Assessment of Missouri Public Drinking Water to Chemical Contamination. For each water supply, the number of water sources potentially affected by atrazine was determined based on the following guidelines.

Wellheads

• Within one mile of an atrazine site
• Within 100 feet of a highway or railroad
• The percentage of the county planted in corn and sorghum

Impoundment intakes

• Drainage basin contained an atrazine site
• A road or railroad is present in the watershed
• The percentage of the county planted in corn and sorghum

River intakes

• Excluded because of the inability to accurately assess the large drainage basins.

Major Findings

• A more accurate method for locating point sources of atrazine (e.g., a warehouse) is highly desirable.
• A statewide land use map could be used to better determine the sub-county locations of cropland and atrazine use. This would greatly reduce the large number of systems potentially affected by the use of atrazine on cropland.

Major Products

A report was developed for EPA which includes a listing of each public water supply and the factors which might affect the water supply.

Investigators: Chris Fulcher, Lois Lenkner and Chris Barnett

Funding Amount: $45,000

Funding Source: U. S. Environmental Protection Agency

Project Duration: October 1992 - June 1993