With the Sonoma-Marin Area Rail Transit district ready to sell bonds and go out to bid for construction, its interim general manager is returning to the position of full-time chief financial officer for those critical tasks.

Day-to-day administration duties, meanwhile, will be turned over to Marin County's public works director, who will temporarily become SMART's executive director, said Sonoma County Supervisor Valerie Brown.

The personnel changes were approved Monday by SMART's executive committee.

"The workload has gotten overwhelming," said Brown, who serves as chairwoman of the SMART board. "We believe that we need to have a different strategy to get things completed."

David Heath, who was hired as SMART's chief financial officer a year ago, has served as interim general manager since Lillian Hames' abrupt resignation in January, while continuing to work as its financial officer with temporary help.

The SMART board on June 15 will interview the top candidates for the general manager's position, Brown said. The position has paid $175,000 annually.

At that June 15 meeting, the SMART board will also work on its construction budget, get a progress report on the sale of construction bonds and go out to bid for the construction of the initial line, Brown said.

Brown said Heath needs to concentrate on those crucial financial issues.

SMART plans to build an initial line from Railroad Square in Santa Rosa to downtown San Rafael, which is estimated to cost $470 million to build and operate over the next 13 years. It is scheduled to open in 2014.

The cost is $109 million more than SMART expects to have from the sale of construction bonds and in local, state and federal funds.

To make up the difference, SMART has approved $88.2 million in cost-saving measures and is working with the Sonoma County Transit Authority, the Transportation Authority of Marin and the Metropolitan Transportation Commission to fill the remaining $21 million gap.

To temporarily run SMART's administration, SMART will be negotiating with Marin County for the services of its public works director, Farhad Mansourian.

Brown said Mansourian will remain a Marin County employee, but spend 90 percent of his time as SMART's top administrative officer. The position is temporary.

"We are a small staff, 14 people, and we need to put them in the right spots," Brown said. "We are doing that today."

SMART will be negotiating with Marin County on Tuesday to determine when Mansourian could start and the cost. Mansourian will not be a candidate for the general manager's position, Brown said.