Robert H. Harris, a scientist with the Environmental Defense Fund, is expected to be named to a seat on the three-member Council on Environmental Quality, administration sources said yesterday.

Harris, 37, has been a leading spokesman on the chronic hazards of toxic chemicals and along with CEQ Chairman Gus Speth, a former environmental attorney, won a landmark case against the Environmental Protection Agency, forcing the agency to meet deadlines for water pollution standards.

Harris will fill a seat on the council left vacant when Speth succeeded Charles Warren as CEQ chairman.

In a telephone interview, Harris said the council "should be involved in looking beyond the current morass of implementing federal statutes," with an eye toward the long-term consequences of environmental problems.

Harris said the federal government has "largely ignored from a regulatory and research view the chronic effects, outside of cancer, of carcinogens" and said he would push for extensive research into consequences of continued exposure to hazardous chemicals.

"The long-term exposures of these chemicals will affect future generations and people's ability to conceive," Harris said. "There is a crying need to develop priorities of which chemicals we should investigate."

A native of West Virginia, Harris holds a doctorate in environmental sciences and engineering from Harvard University and is a former assistant professor of civil engineering at the University of Maryland.