ALBANY, N.Y. (AP) — The state Department of Environmental Conservation has released its proposed plan to review the environmental impact of natural gas drilling in the Southern Tier.

The 45-page document released Monday is the first step in developing supplemental guidelines for issuing permits for gas wells using new horizontal drilling technology.

Gov. David Paterson directed the DEC in July to develop a supplement to the state’s 16-year-old generic environmental impact statement for gas wells to address issues related to the huge volumes of water used in the new technology.

In addition, regulators determined that a supplement was needed to address the impact of possible drilling in the New York City watershed, in or near the Catskill Park, and near the federally designated Upper Delaware Scenic and Recreational River.

“This is just the first step in what will be a careful process designed to look at environmental issues unique to the high-volume hydraulic fracturing of horizontal wells in these deep rock layers,” DEC Commissioner Pete Grannis said. “This review is designed to ensure that if the drilling goes forward, it takes place in the most environmentally responsible way possible.”

A generic environmental impact statement sets requirements all wells must meet, eliminating the need for separate impact statements for each permit application.

Public hearings will be held at six locations in the Southern Tier and Catskills in November and December on the document, which is posted on the DEC Web site at www.dec.ny.gov.

The prospective region for natural gas drilling using the new technology encompasses the Marcellus and Utica shales, geological formations extending from Chautauqua County eastward to Green, Ulster and Sullivan counties in the Catskills and from the Pennsylvania border north to the portion of the New York State Thruway between Schenectady and Auburn.

The DEC noted rock formations that may someday be developed by horizontal drilling exist from the Vermont/Massachusetts border to the St. Lawrence/Lake Champlain region and west along Lake Ontario to Lake Erie. Drilling is prohibited on state-owned land in the Catskills and Adirondacks.

The DEC has received applications for permits to drill horizontal wells in the Marcellus Shale region underlying Chemung, Chenango and Tioga counties and expects to receive applications for areas in Delaware and Sullivan counties. The agency said there is also potential for similar gas exploration in the Utica Shale region, including areas of Otsego and Schoharie counties.

DEC spokesman Yancey Roy said if an energy company wants a permit to drill before the supplemental impact statement is completed, it will have to do a site-specific environmental review. None has chosen to do that, he said.