A Senate committee voted yesterday to reject Gov. Robert L. Ehrlich Jr.'s nominee to head the Maryland Department of the Environment, escalating tensions between the new Republican governor and the environmental community and setting up a high-profile fight on the Senate floor.

Ehrlich had personally lobbied members of the Executive Nominations Committee, calling some at home over the weekend to ask them to support Lynn Buhl, a former automotive industry lawyer and environmental official from Michigan.

After questioning Buhl for nearly an hour, however, the committee voted 10 to 9 to recommend that the Senate reject her. Opponents of the nomination said they fear she would weaken environmental regulations and steer the department too much toward the service of big business and other polluters.

"She is nice. She is very personable. She is very articulate. But in my opinion, she is not the right person for the job," said Senate President Thomas V. Mike Miller Jr. (D-Prince George's), who was among those voting against Buhl. "If she is confirmed, the field will be tilted in favor of people who are not environmentalists."

On the job for nearly a month, Buhl will continue to lead the department unless a majority of the 47 senators vote against her, administration officials said. If that happened, Buhl would be the first Cabinet nominee to be rejected in Maryland since the cabinet system was established in 1969. The full Senate is expected to vote this week.

J. Lowell Stoltzfus (R-Somerset), the Senate minority leader, warned his colleagues not to reject Buhl, saying it would create unnecessary tensions between the General Assembly and Ehrlich. "The Senate has never, never, never denied the appointee of a governor," he said. "If we deny this one, we are sending the wrong message."

Clearly surprised by the loss in committee, administration officials said they would mount an aggressive lobbying campaign on Buhl's behalf. Ehrlich predicted that she would win confirmation on the Senate floor.

"Nobody seems to have any specific problems with her," he said, noting that most of the criticism has been aimed at Buhl's boss at the Michigan agency and at the policies of former governor John Engler, a conservative Republican reviled by environmentalists.

"That is really unfair," Ehrlich said. "She's one of the leading experts on [redeveloping] brownfields, and she's the person I want."

Last week, members of Maryland's influential community of environmentalists announced that they would oppose Buhl, citing concerns that she had been part of the Michigan Department of Environmental Quality, known for rolling back regulations and failing to punish polluters. Their announcement prompted Ehrlich's communications director, Paul E. Schurick, to say the activists had blown their chance to have "a seat at the table" in the new administration.

Buhl's nomination has been by far the most contentious of dozens announced since Ehrlich took office in January as the first Republican governor of Maryland in more than 30 years. The majority have sailed through the Senate committee that vets gubernatorial appointments and the Democrat-controlled Senate with barely a murmur of dissent.

Yesterday, even as the committee gave Buhl's nomination a thumbs down, it approved a long list of others. Among them, Ehrlich's chief campaign fundraiser, Richard Hug, and former governor Marvin Mandel (D) were recommended for confirmation to the University System of Maryland's Board of Regents.

"You'll make a wonderful addition to the board," Sen. Ida G. Ruben (D-Montgomery) gushed to Mandel.

The senators gave Buhl a much less friendly reception, keeping her waiting in the stuffy hearing room while they heard testimony from more than a dozen other nominees.

When she finally took the witness stand, Buhl said she had an 18-year record of fighting for a clean environment as a lawyer for the federal Environmental Protection Agency and DaimlerChrysler Corp. She downplayed her four years heading the Detroit office of the Michigan environmental agency. In Maryland, Buhl said, she would continue a lawsuit over air quality against the federal government. She also made clear that despite Schurick's comments, environmentalists would be welcome at her agency.

"I have felt pretty much for the last week that I'm standing in the center of a storm of controversy," Buhl said. The rhetoric on both sides, she said, had become "a little too shrill."

Under questioning, Buhl acknowledged, however, that she believes Maryland's chief enforcer of environmental regulations has been too "heavily influenced by environmental groups, especially at the exclusion of business. There are other groups besides the environmental groups who want to protect the environment as well. They deserve a voice."

Environmental activists were quick to jump on that statement, and they recounted the story of a failed cleanup in which Buhl allowed the owners of a property leaking toxins into the Detroit River to devise their own cleanup plan. Today, the leak continues, and Buhl conceded that the "innovative approach . . . didn't work."

After voting against Buhl, Sen. Brian E. Frosh (D-Montgomery) said her nomination is a troubling sign of the direction Ehrlich intends to take on environmental policy. "The Ehrlich administration has said unequivocally that they want to turn the Department of the Environment around, that they may even want to abolish it," Frosh said. "This is supposed to be the guardian of the environment. They shouldn't be allowed to turn it into a shill for business."

Staff writer Craig Whitlock contributed to this report.

Lynn Buhl saw herself as "in the center of a storm of controversy."