Chapter 6

Source Water Assessment Reports

The final step in the assessment process will be to develop a report of the assessment findings. Assessment reports will summarize information gained from each step in the assessment process. These assessment reports will be made available to the public.

Assessment reports will include the delineated source water area for each well or intake used by the public water system, major potential sources of contamination within the source water area(s) identified during the inventory, and the susceptibility of the public water system to contamination from identified potential sources of contamination. Because public water systems will often have multiple wells or intakes, an assessment report may include information about more than one water source. Assessment reports will be presented using a combination of maps and brief narratives.

The size of the delineated source water assessment area and the complexity of the contaminant inventory will dictate the type of map that will be provided to the public water system. For example, in most cases, the source water area for a surface water system will be larger than that of a groundwater system and may require the use of a small scale map to reduce the number and size of maps needed for the report. Conversely, source water areas with a high density of potential sources of contamination will require the use of a larger scale map to show all the necessary detail.

Assessment maps will be created in electronic form using either small or large scale data, 1:100,000 or 1:24,000, respectively. The United States Geologic Survey has spatial data, such as section lines, roads, towns, political boundaries, and hydrography available in both of these common mapping scales. United States Geologic Survey 7.5 minute topographic quadrangle maps which have been scanned and converted to digital form are also available. These maps are known as digital rastor graphic maps and contain all the information visible on the original topographic maps.

Assessment reports are, by nature, a summary of the entire assessment process. In addition containing general information, some information will be omitted. Precise intake and well locations will be omitted for security reasons. The entire list of potential sources of contamination identified within the source water assessment area may prove too large to include in its entirety. In such cases, only the potential sources of contamination which pose the greatest threat to the water supply will be indicated on the assessment report map. Likewise, information such as the identity and ownership of these potential sources of contamination are not necessary to assess impacts on a public water system and will not be presented. Complete assessment information will be available upon written request from DEQ.

6.2 Public Water System Involvement

Public water systems will be encouraged to assist with the source water assessments. Their help will be especially beneficial during the contaminant inventory process. Public water systems can verify information compiled by DEQ and help complete the contaminant inventory by providing information about local or historic contaminant sources. Public water systems will be asked to contribute to the assessment report and will also have the opportunity to review the report before finalization. Because the Source Water Assessment Program is a state responsibility, the DEQ will make final determinations regarding information included in the assessment reports. All public water systems will receive a copy of the final assessment report. In addition, public water systems will be expected to publicize the availability of the assessment reports.

6.3 Updating Assessments

Once the initial assessment has been done by DEQ, it will be the responsibility of the public water system to update the source water assessment. DEQ recommends that an assessment be updated every 2 years or whenever significant changes to the system occur. Updating the assessments will be necessary if: a water source is added or removed; significant development within the source water area occurs; land use changes within the source water area are made; or remediation of contaminant sources is completed. Additionally, future federal rules such as Chemical Monitoring Reform, Alternative Monitoring, Ground Water Disinfection, and Enhanced Surface Water Treatment Rules may affect source water assessments. Assessments may need to be updated to reflect changes occurring as a result of these new rules. DEQ will assist with technical aspects of the assessment updates to the extent that funding and resources are available.

6.4 Making The Reports Available To The Public

Section 1453(a) of the 1996 Safe Drinking Water Act Amendments requires states to ensure that source water assessment results are made available to the public. DEQ encourages all public water systems requesting assessments to make the assessment report available to all their customers.

DEQ will provide guidance to the public water system on how to format the notices of availability. A number of different methods will be used to publicize the availability of assessment results. The method used in each case will depend on public water system type.

Community water systems should make and keep several copies at central and easily accessible locations throughout the community. For instance, copies of the report could be kept at the public water system office, county or municipal offices, or the library. Newspaper and radio public service announcements should be developed to make the public aware of the assessment reports and their availability. Similarly, an insert in the monthly bills or even a separate mailer could help advise the public of assessment report availability. Beginning in October, 1999, community public water systems are required to send out a Consumer Confidence Report. Consumer Confidence Reports contain information about both the raw and treated water delivered to public water system customers. As soon as Source Water Assessment results are available, the public water system must include this information about the raw water in the Consumer Confidence Report. The format used for reporting assessment results in the Consumer Confidence Report will be developed by the EPA.

Nontransient noncommunity systems should keep a copy of the report at the business office or work site and post notices of the report availability in locations easily noticed by employees or customers. Transient noncommunity systems should post a copy of the report or a notice of report availability in a conspicuous location.

A copy of all assessment reports will be kept at the main DEQ office and the appropriate district offices. Copies of the assessment report will be available upon written request from these offices. Assessment reports will also be available on the DEQ Internet site. DEQ will publish a list of available assessment reports and where to obtain a copy in its quarterly newsletter as they are completed and become available

Chapters
1 | 2 | 3 | 4 | 5 | 6 | 7
Glossary | Acronyms
Appendices
A | B | C | D
Wyoming's Source Water Assessment Guidance Document Contents