Vulnerability Assessment of Missouri Public Drinking Water to Chemical Contamination

Background

The Federal Safe Drinking Water Act requires that each public water supply routinely monitor for specific chemicals. The Public Drinking Water Program in the Missouri Department of Natural Resources (MoDNR) has the responsibility for testing each public water supply. However, if MoDNR can prove, with a reasonable degree of certainty, that a chemical is not present in an area which would affect a water source, then the test for that chemical at that water source can be waived. Issuance of testing waivers can result in considerable cost savings.

Objectives

• Determine the locations of public drinking water supplies and potential sources of chemical contamination.
• Spatially compare the locations of water supplies and contamination sources to determine whether a test waiver is justified.

Methods

• Methods are based on guidelines developed by the U.S. Environmental Protection Agency (USEPA) and reviewed and approved by MoDNR and USEPA.
• Two major geographic data layers are developed: one containing all public water sources in the state and another containing the potential sources of chemical contamination in the state.
• Locations of contamination sources are determined based on existing state and Federal databases.
• Where locational information is insufficient, additional information is obtained from the MoDNR regional office staff and the Missouri Department of Agriculture.
• Water source information is obtained from the MoDNR regional office staff.
• All geographic information are placed on 1:24,000-scale U.S. Geological Survey topographic quadrangles and incorporated into a Geographic Information System (GIS).
• The GIS is used to determined whether issuing a testing waiver for each public water supply in Missouri is justified.

Waivers are issued based on the following guidelines:

Wellheads:

• Each chemical within a one-mile radius is reported.
• Each highway and railroad within 500 feet is reported to determine the threat posed by the transport of a chemical.
• The percentage of the county planted in seven major crops is reported to determine the threat posed by agricultural chemical use.
• The characteristics of soils and geology within a one-mile radius are reported.

Impoundment intakes:

• Each chemical within the drainage area is reported.
• The length of each highway and railroad within the watershed is reported to determine the threat posed by the transport of a chemical.
• The percentage of the county planted in seven major crops is reported to determine the threat posed by agricultural chemical use.
• The characteristics of soils within the drainage basin are reported.

River intakes:

• Waivers are not issued for river intakes because the chemicals present in extremely large drainage areas cannot be accurately assessed.

Major Findings

• The testing costs for monitoring the public water supplies in Missouri can be reduced from an estimated cost of $16 million to $1.8 million for the 1994-1995 testing period. The testing costs for the 1996-1998 testing period, which includes additional chemicals and classes of public drinking water supplies, can be reduced from $24.1 million to $2.9 million.
• The majority of public drinking supplies are not threatened by potential sources of contamination from the evaluated chemicals.
• Surface water supplies are more likely to be affected by chemical contamination than groundwater supplies.
• The databases used to determine the contamination source locations often contain poor locational information. Assistance of people with local area knowledge is required to map the sites.

Major Products

• A report listing which water supplies should be tested for which chemicals.
• GIS data layers are available via FTP, click here for information.
• A variety of maps ranging from 8.5" x 11" full color "reconnaissance" maps of each wellhead and intake, 17" x 24" county maps and 36" x 48" regional wall maps. View a screen capture of the Bates County Map.

Publications

Fulcher, Chris. Vulnerability of Missouri Drinking Water to Chemical Contamination. Proceedings: Third Annual Water Quality Conference, Center for Water Quality, University of Missouri-Columbia, MO, February 4-5, 1993.

Barnett, Chris, Steve Vance and Chris Fulcher. Vulnerability Assessment of Missouri Drinking Water to Chemical Contamination. Proceedings: Fourth Annual Water Quality Conference, Center for Water Quality, University of Missouri-Columbia, MO, February 3, 1994, pp. 94-99.

Barnett, Chris and Steve Vance. Vulnerability of Missouri Drinking Water to Chemical Contamination. Proceedings: Fourteenth Annual ESRI User Conference, Palm Springs, CA, May 23-27, 1994.

Barnett, C. Vulnerability of Missouri Public Drinking Water to Chemical Contamination. Proceedings: 16th Annual ESRI User Conference, Palm Springs, CA, May 20-24, 1996.

Connett, Dave and Stan Wood. Vulnerability Assessment of Missouri's Public Drinking Water to Chemical Contamination. Poster. ESRI Map Book, Volume 12, June 1997.

Presentations

Fulcher, Chris. Vulnerability of Missouri Drinking Water to Chemical Contamination. Third Annual Water Quality Conference, Center for Water Quality, University of Missouri-Columbia, MO, February 4-5, 1993.

Fulcher, Chris and Chris Barnett. Vulnerability of Missouri Drinking Water to Chemical Contamination: A Spatial Analysis Approach. AWRA 29th Annual Conference and Symposium, Tucson, AZ, August 29 - September 2, 1993.

Barnett, Chris, Steve Vance and Chris Fulcher. Vulnerability Assessment of Missouri Drinking Water to Chemical Contamination. Fourth Annual Water Quality Conference, Center for Water Quality, University of Missouri-Columbia, MO, February 3, 1994.

Barnett, Chris and Steve Vance. Vulnerability Assessment of Missouri Public Drinking Water to Chemical Contamination. Missouri Section AWWA, 1994 Annual Conference, Springfield, MO, April 13-14, 1994.

Barnett, Chris, Steve Vance and Chris Fulcher. Vulnerability of Missouri Drinking Water to Chemical Contamination. Fourteenth Annual ESRI User Conference, Palm Springs, CA, May 23-27, 1994.

Vance, Steve. Vulnerability of Drinking Water to Chemical Contamination. 1994 Midwest/Great Lakes ARC/INFO Users Conference, St. Louis, MO, September 19-21, 1994.

Barnett, Chris and Steve Vance. Vulnerability of Missouri Drinking Water to Chemical Contamination. National Conference on Environmental Problem Solving With Geographic Information Systems, Cincinnati, OH, September 21-23, 1994.

Barnett, Chris. Vulnerability Assessments and Map Reading. Public Drinking Water Program/Regional Office Training, Jefferson City, MO, November 2, 1994.

Barnett, Chris. Vulnerability Assessment of Missouri Public Drinking Water to Chemical Contamination. Fifth Annual Water Quality Conference, Center for Water Quality, University of Missouri-Columbia, MO, February 2-3, 1995.

Barnett, Chris. Vulnerability Assessments. EPA Region VII State Management Plan Workshop, Kansas City, KS, April 4-5, 1995.

Barnett, Chris. Missouri's Natural Groundwater Resources. Missouri State Fair, Sedalia, MO, August, 1995.

Barnett, Chris. Vulnerability Assessment of Missouri Public Drinking Water to Chemical Contamination. Preview Mizzou, Columbia, MO, October 2, 1995.

Barnett, Chris. Vulnerability of Missouri Drinking Water to Chemical Contamination. Sixteenth Annual ESRI User Conference, Palm Springs, CA, May 20-24, 1996.

Connett, Dave and Stan Wood. Vulnerability Assessment of Missouri's Public Drinking Water to Chemical Contamination. Poster. Sixteenth Annual ESRI User Conference, Palm Springs, CA, May 20-24, 1996.

Wood, Stan.  Map Products of the Vulnerability Assessment of Missouri Drinking Water to Chemical Contamination Project. Poster. Mid America GIS Symposium, Lincoln, Nebraska, May 4-7, 1998.

Wood, Stan.  Map Products of the Vulnerability Assessment of Missouri Drinking Water to Chemical Contamination Project. Poster. Seventh Annual International Symposium on Society and Resource Management.  Columbia, Missouri, May 17-31, 1998.

Principal Investigators: Chris Fulcher, Tony Prato and Chris Barnett

Project Managers: Stan Wood and Chris Barnett

Project Staff: Jim Meyer, Yan Barnett, Dennis Reith

Funding Amount:  $1,503,671 (cumulative)

FY92 - $70,000, FY93 - $145,000, FY94 - $132,700, FY95 - $128,719, FY96 - $128,719, FY97 - $128,719, FY98 - $128,719, FY99 - $128,219, FY00 - $128,219, FY01 - $128,219, FY02 - $128,219, FY03 - $128,219

Funding Source: Missouri Department of Natural Resources (MoDNR)

Project Duration: November 1991 - June 2003