As it prepares for permanent closure this spring, the Pactiv Evergreen paper mill in Canton has received two new notices of violation from the N.C. Division of Air Quality, bringing its total violations  since May 2021 to 13.

The first NOV, issued March 24, followed emissions stack testing conducted on the Smelt Dissolving Tank Dec. 6-8, 2022. The mill’s permit limits emissions of black liquor solids to 0.1 grams per kilogram, but the stack test yielded an average rate of 0.15 grams per kilogram, exceeding the federal limit.

The second new violation, issued April 26, came because a monitor installed on the Riley Coal boiler that measures particulate emissions was out of operation far more often than environmental regulations allow. The Division of Air Quality considers monitors that are down more than 6% of the time in any given calendar quarter to be operating with improper operation and maintenance practices. The mill’s third quarter report showed downtime of 9% and the fourth quarter report showed downtime of 17% — nearly triple the allowed amount.

In an April 12 letter, General Manager John McCarthy wrote that the high black liquor reading in the December stack test occurred because the black liquor flow meter for the No. 10 Recovery Boiler was reading artificially low during the testing. This resulted in the smelt dissolving tank being under a heavier load than the meter indicated. The meter is calibrated yearly and had been calibrated on Nov. 1, 2022, about a month before the stack test.

“The fact that a month later the flow meter was already showing signs of decreased flow, came as a surprise,” McCarthy wrote.

The meter has been recalibrated and the boiler cyclone washed since the flow meter issue was identified, and a subsequent stack test in January confirmed that the mill is now in compliance, McCarthy wrote.

“To assure future and current compliance, the facility has held to production limits established by the January 2023 testing and will continue to operate in accordance with the established production limits through the anticipate (sic) shutdown of the mill in late 2023.”

In a May 1 letter, McCarthy wrote that four separate events spurred the excessive downtime behind the second new notice of violation. First, in July 2022 the monitor’s purge blower motor “unexpectedly and suddenly” failed, but a spare was not available locally. The new one took four days to arrive, accounting for 90 of the 198 downtime hours. The second lengthy downtime occurred Aug. 25-29 when the motor failed a second time, requiring a rebuild from a third-party service provider, accounting for 107 of the 198 downtime hours.

Two “consecutive but separate” events spurred the 355 downtime hours recorded in the fourth quarter. Downtime occurred Dec. 16-24 due to a tubing failure that kept the mill from passing daily calibration. Delivery time for replacement tubing “far exceeded our expectation,” McCarthy wrote. Later that same day, an “exceptionally hard and prolonged freeze” is believed to have caused the monitor’s calibration gas regulators to fail prematurely, resulting in downtime through Dec. 29.

During all four outages, scrubber parameters, precipitator voltages and visual emission checks all showed normal operation, McCarthy wrote.

The mill took the Riley Coal burner offline for major mechanical issues with its ID fan on Feb. 21, but after the mill announced its impending closure March 6 it was decided not to repair the fan, so the Riley Coal boiler has not been in use since Feb. 21.

“As such, the facility expects future compliance with the referenced conditions to be maintained via the shuttering of both the source and the mill,” McCarthy wrote.