State officials last week rejected a plan to install diesel engines at the Medical Area Total Energy Plant (MATEP), saying they have not seen evidence of sufficient safeguards for public health.

The May 27 ruling from David E. Fierra, deputy commissioner of the Department of Environmental Quality Engineering, states a new Harvard plan for the facility does not prove its contribution to nitrogen dioxide levels in certain "hot spots" will be insignificant.

Hot spots are areas of heavily congested traffic with already-high nitrogen dioxide levels. "The plan and the record did not identify all the hot spots and didn't outline the impact operating the plant would have on those areas," Fierra said last week.

Baker's Dozen

MATEP, designed to provide chilled water, steam heat and electicity to 13 institutions in the medical area, needs the diesels to be cost-and energy-efficient. But community fears of harmful levels of nitrogen dioxide and carcinogenic emissions have blocked DEQE approval for four years.

L. Edward Lashman, director of external projects, said in a memo last week Fierra had not interpreted the plan's data correctly. He added that he will request Fierra reconsider the case before appealing the ruling through state Superior court.

"With the exception of this unresolved hot spot issue, Mr. Fierra has found that MATEP, in its entirety, would operate safely and would in no way endanger public health," Lashman said. "He has rejected all the arguments by plant opponents to the contrary," he added.

Willard R. Pope '63, general counsel for the DEQE, said last week Fierra could decide simply to review the data himself, or conceivably open the plan to more debate in open hearings.

Anything but....

"We could start the whole hearings process over, but we don't want to do that," Pope added.

Fierra also denied a request by Mission Hill residents that he reopen the hearings to consider further evidence on possible carcinogenic emissions. The ruling says MATEP already has the proper equipment to screen out harmful levels of carcinogens.

Mitchell Hilton, president of the Mission Hill Planning Commission, said yesterday he welcomes the ruling, but added that it may leave the door open for MATEP officials to submit another proposal.

"Their duty was to say 'yes' or 'no' and I hope now they've said 'no'," Hilton said. "If they were allowed to submit a new plan without being required to go through regulatory channels, we would consider that improper," he added.

Mission Hill residents plan to attend a Boston City Council meeting tomorrow night to urge the City to reopen tax and zoning negotiations with MATEP. The residents hope to drive up the plant's operating costs and force it to move.