Supervisor Roger R. Stanton resigned from the Local Agency Formation Commission on Wednesday, becoming the second supervisor to quit the board in the last two months.
Supervisor Thomas F. Riley resigned last month from his position as an alternate to the commission.
Stanton had served on the commission more than seven years. He said he was resigning because he had served long enough and the work was taking an inordinate amount of his staff's time.
The commission is made up of two supervisors, two city representatives and a member of the public. There is also an alternate for each member.
Supervisor Harriett M. Wieder, newly installed chairwoman of the Board of Supervisors, is responsible for appointing the board's representatives to Lafco and other county boards.