After three years as state medical examiner, Dr. Edwin S. Sweeney says he has had enough of the long hours, low pay and poor working conditions.

"It's onward and upward for the Sweeney family from here," he said Thursday. "You could say I've read the tea leaves and saw no immediate improvements in the future."Sweeney said he will resign effective Aug. 26 and take a position with a private firm in Reno, Nev.

Sweeney said his $71,500 annual salary is very low compared to the average medical examiner salaries in the West of about $100,000.

The state medical examiner's office investigates about 2,000 cases a year and performs more than 900 autopsies, he said, He shares the duties with Dr. Todd C. Grey, assistant state medical examiner.

The office is also responsible for certifying the state's more than 9,000 annual deaths, and the two medical examiners also spend many hours testifying and presenting evidence in criminal trials.

"It's gotten really burdensome," he said. "About 200 to 250 cases per examiner would normally be considered a full load, and that's if the examiner has no other responsibilities."

The state plans to have new facilities finished in 1991, but meanwhile medical examiners will have to deal with a plant that is "too small, badly designed, the paint is cracking and there is water dripping from the ceiling," he said.

"You don't need to be an electrician to know you shouldn't have water dripping next to an X-ray machine with thousands of volts," he said.