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Prospect Hill Aquifer - Clarke County, Virginia

Mid-Atlantic Sole Source Aquifers

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Federal Register Notice
Volume: 52
, Issue: 110 , Page: 21733 (52 FR 21733)
Tuesday, June 9, 1987


AGENCY: U.S. Environmental Protection Agency.

ACTION: Notice.

SUMMARY: Notice is hereby given, that, pursuant to section 1424(e) of the Safe Drinking Water Act, the Administrator of the U.S. Environmental Protection Agency has determined that the ground water system of the Stonehenge and Conococheague Limestone formations of the Appalachian Valley Region, which underlies part of Clarke County, Virginia in and around the towns of Boyce and Millwood (denominated the "Prospect Hill Spring Aquifer"), is the sole source or principal source of drinking water for that part of Clarke County, and that such aquifer, if contaminated, would create a significant hazard to public health. This determination is in response to a petition submitted by the Clarke County Board of Supervisors requesting that the Administrator of EPA make a determination pursuant to section 1424(e) of the Safe Drinking Water Act, 42 U.S.C. 300h-3(e), as amended, that the Prospect Hill Spring Aquifer is a sole or principal source of drinking water for the area. As a result of this action, Federal financially assisted projects in the designated area will be subject to EPA review pursuant to section 1424(e) to ensure that these projects are designed and constructed so that they do not contaminate this aquifer so as to create a significant hazard to public health.

DATES: This determination shall be promulgated for purposes of judicial review at 1:00 p.m. eastern standard time on June 23, 1987. This determination shall become effective on July 23, 1987.

ADDRESSES: The data on which these findings are based are available to the public and may be inspected during normal business hours at the U.S.Environmental Protection Agency, Region III, Drinking Water/Ground Water Protection Branch, 841 Chestnut Building, Philadelphia, Pennsylvania 19107. [Information is out-of-date.]

FOR FURTHER INFORMATION CONTACT: Stuart Kerzner, Drinking Water/Ground Water Protection Branch, U.S. Environmental Protection Agency, Region III at the above address or at (215) 597-3527. [Information is out-of-date.]

SUPPLEMENTARY INFORMATION: Pursuant to section 1424(e) of the Safe Drinking Water Act, 42 U.S.C. 300h-3(e), the Administrator of the U.S. Environmental Protection Agency has determined that the aquifer, known as the Stonehenge and Conococheague Limestone formations is the sole or principal source of drinking water for the areas in and around the towns of Boyce and Millwood. This aquifer supplies drinking water to public water systems and individual (single family) wells. Pursuant to section 1424(e), Federal financially assisted projects, constructed on the denominated "Prospect Hill Spring Aquifer" or within its stream flow source zone, will be subject to EPA review.

I. Background

Section 1424(e) of the Safe Drinking Water Act states:

(e) 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 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 financial assistance may, if authorized under provision of law, be entered into to plan or design the project to assure that it will not so contaminate the aquifer.

On June 27, 1985 the Board of Supervisors of Clarke County, Virginia, petitioned the Administrator of EPA, pursuant to section 1424(e) of the Safe Drinking Water Act, to designate portions of the Stonehenge and Conococheague Limestone formations in Clarke County, Virginia, denominated "Prospect Hill Spring Aquifer", as the sole or principal source of drinking water for an area, which, if contaminated, would create a significant hazard to public health. A notice of receipt of this petition, together with a request for comments, was published in the Federal Register on October 31, 1985 (50 FR 45484).

The single public comment received recommended the designation. Because there were no requests for a public hearing and the one public comment received was favorable, a public hearing was deemed unnecessary. Upon review of the petition, EPA has determined that the stream flow source zone of the designated aquifer is a portion of the drainage basin of Page Brook.

II. Basis for Determination

On the basis of the information which is available to this Agency, the Administrator has made the following findings, which are the basis for the determination noted above:
1. The "Prospect Hill Spring Aquifer" underlying the designated area is the sole drinking water source for this area. The Clarke County Sanitation Authority derives above 35,000 gallons per day (gpd) from the Prospect Hill Spring to serve about 575 people. The water is chlorinated. The remaining residents in the designated area, approximately 125 people, have private wells, which supply, collectively, about 8,000 gpd. EPA has determined that the "Prospect Hill Spring Aquifer" supplies 100 percent of the drinking water to the population.

2. There is no existing alternative drinking water source which provides 50 percent or more of the drinking water to the designated area. This is because this area is rural in nature and the nearest existing alternative supply, the Shenandoah River, is at such a distance that its use would be technically and economically impractical.

3. The designated portion of the "Prospect Hill Spring Aquifer" is susceptible to contamination, through the recharge or stream flow source zone, from abandoned wells, septic tanks and agricultural activity in which fertilizers, herbicides, and pesticides are applied directly to the soil surface. In 1981 the local Health Department discovered the presence of high nitrate levels in two municipal water source wells in the Town of Berryville. Other tests revealed the presence of several types of herbicides in one well and two or three types of phenols which may originate from pesticides in both wells. These wells are recharged by the same stream flow zone as that of the "Prospect Hill Spring" aquifer. Since the ground water contamination can be difficult or impossible to reverse, and because this aquifer system is heavily relied upon for drinking water purposes by the general population, contamination of the aquifer would pose a significant hazard to public health.

III. Description of the Designated Portions of the Stonehenge and Conococheague Limestone Formations and their Stream Flow Source Zones

The Stonehenge formation of lower Ordovician age is approximately 700 to 800 ft. thick and consists predominantly of thin to medium bedded, light to dark gray pure limestone. The older Conococheague formation of Upper Cambrian Age, consists of gray to dark gray limestone with interbeds of dolomite and sandstone. The Conococheague is approximately 2300 ft. thick. The area over which Federal financially assisted projects will be reviewed includes both the designated portions of the Stonehenge and Conococheague formations, encompassing the "Prospect Hill Spring Aquifer" and their stream flow source zone. This designated area consists of the following: the area directly overlying the Stonehenge and Conococheague formations in and around the towns of Boyce and Millwood and their stream flow source zone. The stream flow source zone includes the drainage basin of Page Brook from its headwaters to a point on Page Brook 3000 feet north of its confluence with Roseville Run. The majority of this drainage basin consists of the Rockdale Run limestone and dolomite formation, with portions of the Oranda, Edinburgh, Martinsburg and Lincolnshire limestone and dolomite formations comprising the remainder.

The surface area of the "Prospect Hill Spring Aquifer" is about one square mile, and the area of the stream flow source zone is approximately twelve (12) square miles. An enlarged map of the area and all the information utilized in this determination, which includes the petition, written comments, and various technical publications, are available to the public and may be inspected during normal business hours at the office of the U.S. Environmental Protection Agency, Region III, 841 Chestnut Building, Philadelphia, Pennsylvania 19107. [Information is out-of-date.]

IV. Project Review

On September 29, 1977 EPA proposed regulations for implementing section 1424(e) of the Safe Drinking Water Act (42 FR 51620). The proposed regulations contain procedures for review of Federal financially assisted projects which could contaminate "sole or principal source" aquifers through the recharge zone so as to create a significant hazard to public health. They are being used as interim guidance until final regulations are promulgated.

EPA Region III is already working with the Federal agencies which may in the future sponsor projects in the area of concern in order to develop interagency procedures whereby EPA will be notified of proposed commitments for projects which could contaminate the designated aquifer. EPA will evaluate such projects, and, where necessary, conduct an indepth review, including soliciting public comments where appropriate.

Although the project review process cannot be delegated, the Regional Administrator in Region III will rely to the maximum extent possible upon any existing or future State and local control mechanisms in protecting the ground water quality of the aquifer underlying the designated area. Included in the review of any Federal financially assisted project will be coordination with the State and local agencies. Their comments will be given full consideration and the Federal review process will function so as to complement and support State and local mechanisms.

Dated: May 21, 1987.

James M. Seif,
Regional Administrator.

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