Fire officials say damage from the fire at the Methane Collection Lagoon north of J-B-S at Marshalltown did a half million dollars in damage. The fire broke out Saturday morning about 10:30 a-m according to Assistant Fire Chief Christopher Cross. Fire crews battled the blaze for some three hours, a part of Marion Street and North 18th Avenue had to be closed to traffic for a time. The cause was unknown at last report and an investigation is underway. Crews used both attack hose lines and elevated master streams. No one was hurt and the plant remained in operation.