Sole Source Aquifer Designation of the Guemes Island Aquifer System; Skagit County, Washington

I. Background

Section 1424(e) of the Safe Drinking Water Act, 42 U.S.C. 300h- 3(e), Public Law 93-523, states:

If the Administrator determines, on his own initiative or upon petition, that an area has an aquifer which is the sole or principal drinking water source for the area and which, if contaminated, would create a significant hazard to public health, he shall publish notice of that determination in the Federal Register. After the publication of any such notice, no commitment for Federal financial assistance (through a grant, contract, loan guarantee, or otherwise) may be entered into for any project which the Administrator determines may contaminate such aquifer through a recharge zone so as to create a significant hazard to public health, but a

commitment for Federal assistance may, if authorized under another provision of law, be entered into to plan or design the project to assure that it will not so contaminate the aquifer.

On August 1, 1994, EPA Region 10 received a petition from the President of the Guemes Island Properties Association requesting that EPA designate the Guemes Island aquifer system as a sole source aquifer (SSA). The petition expressed several reasons for interest in a designation, including concern that an increasing island population could adversely affect both ground water quality and quantity due to impacts from logging, road building, and onsite septic systems on aquifer recharge areas, and from the impact of ground water withdrawals from new wells; a desire to raise public awareness about the vulnerability of the aquifer system; a desire to raise awareness about existing and future problems of the water supply to Skagit County government; and the value of SSA status in future grant applications for further study of the island's ground water. A detailed review of the petition by EPA was delayed for about three years due to work on an earlier designation request. In July of 1997, the Guemes Island review was completed and the area appeared to meet all criteria for SSA designation. The legal and technical basis for the proposal was outlined in an EPA publication titled: ``Support Document for Sole Source Aquifer Designation of the Guemes Island Aquifer System,'' EPA 910/R-97-006.

II. Basis for Determination

Among the factors to be considered by EPA in connection with the designation of an area under section 1424(e) are: (1) Whether the aquifer is the area's sole or principal source of drinking water; and (2) whether contamination of the aquifer would create a significant hazard to public health. EPA Region 10 has further interpreted the statutory language so that ``sole or principal'' means that the aquifer must supply at least 50 percent of the drinking water for the area. Furthermore, there should be no alternate drinking water source(s) which can physically, legally, and economically supply all those who depend upon the aquifer for drinking water, should it become contaminated. In addition, aquifer boundaries should be delineated based on sound hydrogeologic principles and the best available scientific information. Although designation determinations are largely based on science- based criteria, the Regional Administrator may also consider the overall public interest and net environmental and public health benefits in making a sole source aquifer determination. On the basis of information available to this Agency, the Region 10 Administrator has made the following findings:

(1) The aquifer system is the principal source of drinking water (close to 100%) for people on the island and there are no alternate sources which can physically, legally, and economically supply all those who depend upon the aquifer for drinking water, should it become contaminated. Potential alternate sources considered include surface water, water piped in from the mainland, bottled water, rainwater catchment, and reverse osmosis of seawater. None of these drinking water sources are considered by EPA to be feasible replacements for the entire aquifer system due to economic barriers or because these sources are not consumed or utilized for domestic purposes in significant quantities. (2) Contamination of the aquifer system would create a significant hazard to public health. The aquifer system is vulnerable to contamination through its recharge zones from various sources and activities including onsite septic systems, stormwater runoff, animal wastes, and pumping wells which can cause intrusion of seawater into freshwater aquifers. Scientific information indicates there is a hydrogeologic interconnection between the aquifers underlying the island, and collectively, they may be considered as a single aquifer system. Because they are interconnected, there is the potential for cross- contamination from one aquifer to another.

Because the aquifer system is vulnerable to contamination and restoring ground water quality can be difficult or even impossible; and because the aquifer system is the principal source of drinking water for the area and there are no other sources which can economically supply all those who depend upon it for drinking water; EPA believes that contamination of the aquifer system would pose a significant hazard to public health. These findings are based on information from various sources including the petition, EPA guidances, a U.S. Geological Survey report, public comments, the Skagit County Health Department, and the Washington State Department of Health.

III. Description of the Guemes Island Aquifer System

The following is a summary of information from the Support Document available upon request from EPA Region 10. Much of the hydrogeological information in the Support Document is taken from the petition and from ``Hydrogeology and Quality of Ground Water on Guemes Island, Skagit County, Washington,'' U.S. Geological Survey (USGS) Water-Resources Investigations Report 94-4236, by Kahle and Olsen, 1995. Guemes Island is a small island in Puget Sound, located north of the City of Anacortes in the western part of Skagit County, Washington. The total area of the island is approximately 8.2 square miles. The year-round population of the island is approximately 540, with a summer population which nears 2,200. The southeastern part of the island is hilly and composed of bedrock and fractured rock; the remainder is gently rolling and overlain by glacial drift. There are eight distinct geologic units present on Guemes Island: consolidated bedrock, glacial deposits comprised of the Double Bluff Drift, Whidbey Formation, Vashon advance outwash, Vashon till, and Everson drift, and more recent units composed of peat and beach deposits. There is considerable variation in the thickness of individual units, and not all units are necessarily present at any one location. Glacial and recent deposits are at the land surface over most of the island, with bedrock exposed only on the southeastern end of the island. Highly permeable units within the glacial deposits also function as the main aquifers under the island. These units are hydraulically connected and thus perform as an aquifer system. Ground water quality on Guemes Island is considered to be generally of good quality. The aquifer system underlying the island is considered to be vulnerable to contamination due to the highly heterogeneous nature of the sand and gravels making up the aquifers, and the inconsistent confining nature of the surficial confining unit and the Whidbey confining unit. Chlorides and nitrates are the contaminants of the most concern. High chloride concentrations in well water on the island are due to either the presence of relict seawater in aquifer materials, or seawater moving inward from Puget Sound (seawater intrusion). Excessive ground water withdrawal in a near-shore area can cause large local movement of the freshwater-seawater interface especially if the aquifer is thin. Nitrates in ground water can originate from septic tanks, animal wastes, and fertilizer. The Guemes Island SSA boundaries are representative of an aquifer system that encompasses the entire Guemes

Island area. The aquifer system is bounded on all sides by Puget Sound. The vertical extent of the aquifer system at depth includes all potable water-bearing geologic units underlying the island, including both the unconsolidated glacial deposits and the bedrock unit. Please see the Support Document for a more detailed hydrogeologic description.

IV. Project Reviews

The Safe Drinking Water Act authorizes EPA to review proposed Federal financially-assisted projects which have the potential to contaminate a designated SSA. Federal assistance may be denied if EPA determines that a project may contaminate the SSA through its recharge zone so as to create a significant hazard to public health. Outright denial of Federal funding is rare as most projects pose limited risk to ground water quality or can be feasibly modified to prevent ground water contamination. Proposed projects that are funded entirely by state, local, or private concerns are not subject to SSA review by EPA. EPA does not review all possible Federal financially-assisted projects, but tries to focus on those projects which pose the greatest risk to public health. Memorandums of Understanding have been developed between EPA and various Federal funding agencies to help identify, coordinate, and evaluate projects. EPA relies to the maximum extent possible on existing local and state mechanisms to protect SSAs from contamination. Whenever feasible, EPA coordinates project reviews with local and state agencies that have a responsibility for ground water protection. Their comments are given full consideration in the Federal review process.

V. Public Participation and Response to Comments

The following is a summary of information from the ``Response to Public Comments for the Guemes Island Sole Source Aquifer Proposal'' available upon request from EPA Region 10. EPA used various methods to notify and involve the public and others in the Guemes Island SSA designation process. The outreach effort included briefings to local and State government, distribution of EPA facts sheets, placing information in local libraries, a public advertisement in the local newspaper, and providing information for several newspaper and newsletter articles. A public comment period was in effect from August 27 to October 11, 1997, and a public meeting was conducted on the island by EPA staff on September 19, 1997. The purpose of the meeting was to present information about the proposal, answer any questions, and take public comments directly from the island community or other interested parties. About 40 people attended the meeting. Written comments were accepted on the proposal until the end of the public comment period. All comments were reviewed and considered by EPA, but did not lead to any changes to EPA's determination that Guemes Island qualifies for SSA status. During the comment period, EPA received fourteen written comments in the mail and ten oral comments at the public meeting. Of the written comments, ten persons expressed support for the designation, while four opposed it. Formal comments at the public meeting were evenly split with five persons supporting the designation and five opposed. Individuals submitted most of the comments, but a community organization and a State agency also commented. The primary reason given for supporting the proposed action was a belief that the designation would increase protection of the islands ground water. Many cited the educational benefit that SSA status would have on island residents and on Skagit County government on the source of the island's drinking water, its value and vulnerability, and the need for protection and conservation. Some people commented that protection of the island's ground water was important because there are no feasible alternate sources of drinking water. Some people felt that ground water would be better protected because of additional environmental review of proposed projects, or because it could hinder the siting of future landfills on the island. Some supported the designation because they felt that added protection of the island's drinking water could help to protect property values. Several people opposed the designation because they did not want an increase of Federal involvement in local affairs. In response, the SSA program can increase Federal involvement, but only in a very limited way--if Federal assistance is proposed for a project, EPA can review the proposal and ask for changes if drinking water supplies are endangered. This review process is meant to support and enhance, rather than duplicate or supplant, local ground water protection measures. Many communities welcome the technical assistance and coordinating services they receive from EPA to protect their drinking water. Some people commented that the designation would not contribute to further ground water protection. In response, the SSA program is not intended to be a comprehensive ground water protection program. EPA authority is limited to the review of Federal projects, which are likely to be minimal in number and scope for the island. However, there are many other benefits from an SSA designation, that can be locally- driven, such as greater awareness and stewardship of a community's drinking water supply. This can lead to an increase of both individual and local governmental actions to protect the resource. Two persons commented that SSA designation was unnecessary because the island's ground water was not already contaminated. In response, the SSA program is a pollution prevention program. Experience has shown that it is much smarter, and considerably less expensive, to prevent ground water pollution in the first place, rather than trying to clean up a degraded water supply after a problem is discovered. Two persons objected to the designation because they believed that the petitioner had requested a part of the island be excluded from the designated area. In response, the original petition correctly identified that at least one portion of the island (a bedrock tip area that discharges ground water to Puget Sound) could be viewed as a hydrogeologically separate part of the island. However, the petition specifically requested that the entire island be designated as a sole source aquifer. EPA concurred that it made better technical and programmatic sense to designate the entire island. One person raised questions on the technical basis for the designation, claiming that the extent and accuracy of the data used in the petition and in EPA's Support Document was lacking and flawed. In response, EPA used the best available scientific information and best professional judgement and believes that the technical basis for the designation is based on sound hydrogeologic principles.

VI. Economic and Regulatory Impact

Pursuant to the provisions of the Regulatory Flexibility Act (RFA), 5 U.S.C. 605(b), I hereby certify that this final determination will not have a significant impact on a substantial number of small entities. For purposes of this Certification, the ``small entity'' shall have the same meaning as given in section 601 of the RFA. This action is only applicable to Guemes Island. The only affected entities will be those businesses, organizations, or

government jurisdictions that request Federal financial assistance for projects which have the potential for contaminating the aquifer system so as to create a significant hazard to public health. EPA does not expect to review small isolated commitments of Federal financial assistance on an individual basis, unless a cumulative impact on the aquifer is anticipated. Accordingly, the number of affected small entities will be minimal. For those small entities which are subject to review, the impact of today's action will not be significant. Major projects subject to this review will be proceeded by a ground water impact assessment required pursuant to other Federal laws, such as the National Environmental Policy Act (NEPA) as amended 42 U.S.C. 4321, et seq. Integration of those related review procedures with SSA review will allow EPA and other Federal agencies to avoid delay or duplication of effort in approving financial assistance, thus minimizing any adverse effect on those small entities which are affected. Finally, today's action does not prevent grants of Federal financial assistance which may be available to any affected small entity in order to pay for the redesign of a project to assure protection of the aquifer system. Under Executive Order 12866, EPA must judge whether a regulation is ``major'' and therefore subject to the requirement of a Regulatory Impact Analysis. This action is not major because it will not have an annual effect of $100 million or more on the economy, will not cause any major increases in costs or prices, and will not have significant adverse effects on competition, employment, investment, productivity, innovation, or the ability of United States enterprises to compete in domestic or export markets.

VII. Summary

This determination affects only the Guemes Island aquifer system located in Skagit County, Washington. As a result of this determination, all Federal financially-assisted projects proposed in the designated area will be subject to EPA review to ensure that they do not create a significant hazard to public health.

Dated: November 18, 1997. Chuck Clarke, Regional Administrator,U.S. Environmental Protection Agency, Region 10. [FR Doc. 97-31273 Filed 11-28-97; 8:45 am] BILLING CODE 6560-50-F