A Tacoma tideflats paper mill that specializes in packaging has been fined $52,500 by the state Department of Ecology (DOE) for failing to adequately treat hazardous air pollutants. WestRock Co., which occupies the end of the peninsula between the Puyallup and Middle waterways, failed a performance test on April 17 when it insufficiently reduced hazardous air pollutants in the mill’s wastewater streams, DOE said in a press release. Those levels must meet levels set in WestRock’s air quality permit. The permit requires WestRock to treat hazardous air pollutants dissolved in certain wastewater streams generated during the paper-making process. The main pollutant is methanol, DOE said.