The city will perform maintenance on grinder pumps used for the piped sewer system. The charges will only be assessed if repair is attributed to negligence, as determined by the public works utilities maintenance foreman. At the time the customer receives service to rebuild, repair or replace a grinder pump, the customer will be billed for the following charges in relation to the annual frequency with which a grinder pump is rebuilt, repaired or replaced: If the property that receives the repair or replacement is a multi-dwelling unit, then the person whom the water account’s name is in is responsible for the expense.