The construction of offshore ''electric generating stations'' is legally restricted inside the five state-designated ocean sanctuaries.

Pritchard, who recently left his environmental post to work on Gov. Mitt Romney's Big Dig safety review, also noted that Cashman's sites are home to a primary nesting area for the federally endangered roseate tern, as well as other threatened bird species.

Yesterday, a spokesman for Cashman said the state's concerns came as no surprise.

''It wasn't unexpected, so it doesn't really deter us,'' said Todd Presson, director of wind energy development for Patriot Renewables, the renewable energy subsidiary of Jay Cashman Inc. ''It lays out a little more clearly what we need to do and the questions we need to answer in order for a project like this to go ahead.'' The Buzzards Bay project would include three clusters of turbines off Fairhaven, Dartmouth and Naushon Island, one of the Elizabeth Islands.

The state first raised concerns about the sanctuary status at a Fairhaven public hearing in July. At the time, Cashman said the project might be permittable under a section of the sanctuary act that allows offshore power cables and gas pipelines.

In his 23-page report, Pritchard flatly ruled that Cashman's proposal did not fall into that category.

Still, Presson said the law is unclear and that some state lawmakers are pushing legislation that might establish improved guidelines for offshore renewable projects within sanctuary areas.

''Clearly there's some ambiguity in the law that we're going to have to address,'' he said.

State Sen. Robert O'Leary, D-Barnstable, has been pushing ocean management legislation on Beacon Hill since 2005. His bill passed the Senate in July but did not pass the House before the legislative session ended.

Last night, he said his bill would allow only small-scale renewable energy projects in the designated waters.

''No one would define the Cashman project as small-scale,'' O'Leary said, adding that amending his bill to accommodate the developer's proposal would be ''a mistake.''

The other option, he said, would be for Cashman to seek legislation specifically approving the proposal - a move the senator called ''a Pandora's box.''

The Cape Wind proposal, which would include 130 turbines in the federal waters of Nantucket Sound, has not faced the same hurdle at the state level.

''The issues the Cashman site are dealing with right now are not the same as the Cape Wind project,'' explained Cape Wind spokesman Mark Rodgers. ''The federal portions of Nantucket Sound are not part of the Cape and Islands Ocean Sanctuary.''

Cashman has said that Cape Wind developer Jim Gordon's site is the best location for an offshore wind farm along the Massachusetts coastline because of the winds, the shallow ocean depths and the footprints federal status.

The Buzzards Bay developer has a personal interest in the Cape Wind proposal, which remains under federal, state and local review. If Cape Wind ultimately did receive permits to move forward, Cashman, who has a home in West Falmouth, has expressed interest in overseeing construction.

Seth Kaplan, a senior attorney at the Conservation Law Foundation, said Cashman's Buzzards Bay proposal demonstrates the need for state officials to update and clarify the 35-year old Ocean Sanctuaries Act. The outlook for Cashman under the current law, he added, will likely make financing the $750 million project a particular burden.

The next step for Cashman, according to environmental affairs spokesman Vanessa Gulati, would be filing a draft environmental report that addresses the issues raised in the state report.

Presson, the project's spokesman, said some of the research the state has requested - including bird studies - is already under way. ''We're not slowing down,'' he said.

David Schoetz can be reached at dschoetz@capecodonline.com.