AUGUSTA – Bath Iron Works has notified union officials that it plans to lay off 90 production workers next month.

The shipyard employs about 5,900 people in all. The production force can rise and fall depending on fluctuations in workload.

BIW spokesman Jim DeMartini confirmed late Friday that the planned layoffs would affect 40 electricians, 35 preservation technicians and 15 welders.

Layoffs would take effect Oct. 10.