Subject to the utility's rules setting forth the method of determining a reduced rate herein authorized, if an accidental ground is found on a customer's wiring or equipment, the utility may estimate the kilowatt-hours lost and bill for them at a reduced rate not less than the generated or purchase cost of the energy, but no such adjustment shall be made for energy supplied after the customer has been notified and has had an opportunity to correct the condition. Any demand (kilowatt) caused by an accidental ground may be billed at a rate lower than that filed for the class of service involved. The utility shall notify the customer of the ground whenever it is found or suspected.
Wis. Admin. Code Public Service Commission PSC 113.0925