A federal judge has thrown out several components of a discrimination lawsuit against the Parks and Recreation Department, ruling that the city agency did not create a hostile work environment for black and Hispanic employees.

But the judge, Denny Chin of U.S. District Court in Manhattan, left intact the core of the class action lawsuit. Rejecting the city’s motion to dismiss the entire case, Judge Chin found that there is evidence to suggest that the Parks Department failed to promote or pay black and Hispanic employees on an equal basis with whites. In an 82-page decision, Judge Chin also said there is evidence to suggest that the Parks Department retaliated against employees who complained, noting that two plaintiffs were transferred to work in basements after they reported discrimination.

The whittled-down set of allegations that results from Judge Chin’s decision, which came down Friday, closely resembles the claims contained in a lawsuit the Justice Department filed against the Parks Department in 2002. That lawsuit, which the city settled last year, focused on how the department distributed its promotions. As part of the settlement the Parks Department pledged to posts all job openings and promised to take steps to ensure promotions are made on the basis of performance. The settlement did not provide compensation.

The class action lawsuit scrutinizes longtime Parks Commissioner Henry Stern, who left the post in 2002. Past statements by Mr. Stern are considered in the decision and will likely play a large role in a trial. Mr. Stern, Judge Chin notes, did not order any investigation into the appearance of three nooses hung on Parks Department property even after there were complaints. In one instance a picture of a black man was drawn on the wall behind the noose, the decision notes.

While Judge Chin did not signal what he makes of the evidence regarding nooses, the judge ruled that Mr. Stern’s statements were “insufficient to show that racial harassment was standard operating procedure at Parks.”Judge Chin also ruled threw out claims that the Parks Department underfunded parks in predominately black and Hispanic neighborhoods or only assigned minority employees to those areas.

A lawyer for the city, Kathleen Comfrey, said in a statement, “We fully expect that the plaintiffs’ remaining claims will be rejected after a review of all of the evidence at trial.”

But an attorney representing the plaintiffs, Lewis Steel, said that Judge Chin’s ruling gives substantial credibility to the claims of the 11 former and current employees named in the legal complaint.

“This is basic old-fashioned racial discrimination which has been allowed to fester in our society for years,” Mr. Steel said. “And this judge in this opinion put the city on notice that there is substantial and concrete evidence that these problems exist here.”

Judge Chin wrote that the “plaintiffs have presented substantial, concrete evidence to support their claims of discrimination and retaliation.” The Judge states that in 2000, 92.9% of the Parks employees earning less than $20,000 a year were black or Hispanic, while 14.2% of those earning between $50,000 and $60,000 were black or Hispanic.

The lawsuit represents about 3,000 current and former minority Parks Department employees, another lawyer representing the plaintiffs, Cynthia Rollings, said.