The department, whose mission it is to regulate hazardous waste, oversee cleanups and prevent pollution, will assume the role of lead agency for the Stauffer/Zeneca site, and the UC Richmond Field Station, CalEPA Secretary Alan Lloyd said in a prepared statement Monday.

The Richmond City Council and the Contra Costa County Board of Supervisors had each voted to support a request by Assemblywoman Loni Hancock, D-Berkeley, to give the toxics department ultimate oversight for the project.

"The challenges presented by these sites, as well as their close proximity to one another and nearby residences and businesses, warrant a single regulatory oversight agency," Lloyd's statement says.

Until now, the toxics department shared oversight with the San Francisco Water Quality Control Board. While the board regulates cleanup of sites posing a threat to water quality, critics complained that the agency did not have the toxicologic expertise to manage such a complex project.

"It's a wonderful sense of accomplishment to know that we, as a community, have achieved this success," said Richmond Councilwoman Gayle McLaughlin, who introduced the local resolution.

She also said the community must continue to aggressively monitor progress at the site.

Developer Cherokee Simeon is prepping the waterfront property off Interstate 580 in south Richmond, formerly Stauffer Chemical, then Zeneca, for possible development as a business park and housing to be called Campus Bay.

Years after the pesticide manufacturing operation shut down, tests revealed heavy metals, PCBs and volatile compounds in the soil and marsh mud.