THE head of the Esperance Port Authority, which was at the centre of the southern Western Australian town's lead contamination crisis, has announced he is retiring.

A parliamentary inquiry this month investigated why mining company Magellan Metals transported and exported lead carbonate through the port in the powdered form rather than in pellets.

More than 4000 birds have died from lead poisoning around Esperance since December and 13 residents, including two infants, have recorded high lead levels.

High readings of lead and nickel have also been found in rainwater tanks around the town.

Last month, Planning and Infrastructure Minister Alannah MacTiernan, who is coordinating the government's response to the crisis, told parliament the Port Authority had failed in its handling of the lead.

The Authority's chief executive officer Colin Stewart announced today he would retire at the end of July.

"In order to best pursue the challenges facing the port, I am of the view that by stepping aside the board and my successor will be best able to plan and implement changes," Mr Stewart said.

"I particularly thank all employees for their great support and assistance during the recent difficult times experienced by all Esperance residents."

The parliamentary inquiry is due to report back to the Legislative Assembly by August 16.