By contrast, other sources claim that the fire had started the previous day, when a trash hauler dumped hot ash or coal discarded from coal burners into the open trash pit. The author of "The Day the Earth Caved In" noted that borough council minutes from June 4, 1962, referred to two fires at the dump and that five firefighters had submitted bills for "fighting the fire at the landfill area." The borough, by law, was responsible for installing a fire-resistant clay barrier between each layer of the landfill, but fell behind schedule, leaving the barrier incomplete. This allowed the hot coals to penetrate the vein of coal underneath the pit and start the subsequent subterranean fire.