Pulp and paper manufacturers challenged EPA's adoption of regulations under the Clean
Water Act. Disputes erupted over EPA's change of calculations of the secondary waste load for mills at 487 pounds of waste to be treated per ton of product, a figure to which the industry did not object, to a lower figure of 404 pounds per ton. The EPA claimed that it arrived at the new lower figure by disregarding two factors it had taken into account in its previous determination as they canceled each other out. However, the record of the proceedings made no mention of the two factors much less their mode of being considered.