As the nation's 155 bleached pulp mills begin digesting the abysmally technical EPA "cluster" rule-it is only 1 pages long notes a bemused Georgia-Pacific executive-it is the packagers using bleached board who may develop heartburn. One official at Procter & Gamble Cincinnati OH cleared a formal statement for Packaging World through a number of company executives only to have the public relations department quash it at the 11th hour. Besides being a behemoth buyer of paperboard packaging P&G has its own pulp mill too. It mostly manufactures products like toilet tissue and paper towels but it also makes corrugated boxes. Announced in mid-November the cluster rule is a double whammy of sorts: It requires bleached pulp mills to reduce both air and water emissions. The rule forces mills to get sulfur emissions out of the air and the chlorine out of the water just to mention two of the many chemicals targeted. The big cost for the mills will be the elimination of elemental chlorine (and substituting chlorine dioxide) in the bleaching process.