With another round of cabinet nominations expected this week, the former commissioner of New Jersey's Department of Environmental Protection is emerging as a leading candidate for the top environmental post in the Obama administration.

Lisa Jackson, the cochair of President-elect Obama's transition team on energy and natural resources, is a top candidate to be named administrator of the Environmental Protection Agency, according to two Capitol Hill Democratic aides and New Jersey environmental and business leaders who have been in touch with members of the Obama transition team. All wanted to remain anonymous since they are not authorized to speak for the team.

Several sources, including one of the Democratic aides, however, said there has not been a final decision from the Obama team.

Along with Jackson - who stepped down as DEP commissioner on Dec. 1 to become New Jersey Gov. Corzine's chief of staff - California Air Resource Board chief Mary Nichols is said to be a top contender for the EPA job.

Meanwhile, Kathleen McGinty, the former secretary of Pennsylvania's Department of Environmental Protection, who also was on the short list for EPA administrator, has pulled out of the running because of family issues, according to close associates.

McGinty, of Philadelphia, told associates late last week that she decided not to pursue the post because of serious illnesses in her family and the demands of raising three young daughters.

Another EPA contender, Kansas Gov. Kathleen Sebelius, removed herself Saturday from consideration for a spot in Obama's cabinet, citing among her reasons her state's budget problems.

Jackson, 46, was appointed New Jersey's top environmental officer in 2006 and has won praise from environmentalist and business leaders for balancing the needs of industry with the environment.

If she is selected, Jackson would be the first African American to hold the position of EPA administrator.

Jackson holds a chemical engineering degree from Princeton University, and has spent more than 20 years in environmental work at the federal, regional and state levels.

Jackson spent 16 years with the EPA, first in Washington and then at its regional office in New York, where she helped to oversee the Superfund program, which cleans some of the nation's most polluted sites. In 2002, she joined the New Jersey Department of Environmental Protection.

During her tenure, Corzine unveiled a much-trumpeted goal to cut greenhouse gas emissions 20 percent by 2020 and 85 percent by 2050.

"Lisa is passionate about the environment while being fair-minded, practical and sensitive to the needs of business," Assemblyman John McKeon, a Democrat who chairs the New Jersey Assembly's environment committee, wrote in a letter to Obama last week.

Some environmentalists, however, have criticized Jackson, saying she has been too easy on business and failed to follow through with the substantive steps to back up her positive headlines.

They point in particular to a recent EPA report that faulted New Jersey, and the federal government, for moving too slowly to clean up contaminated sites.

Contact staff writer Amy Worden at 717-783-2584 or aworden@phillynews.com.