Mike Terry, Deseret News
A group of workers at the Holly Refinery in West Bountiful, Utah, March 20, 2008.

SALT LAKE CITY  — With haze-filled skies dominating much of the Wasatch Front, some clean air advocates are renewing their criticism of plans by Holly Refinery to nearly double the amount of crude oil it can process at its Davis County plant.

A hearing to solicit public input on the permit modification is set for 6 p.m. Thursday in the board room of the Multi Agency State Office Building, 195 N. 1950 West.

The state Division of Air Quality has been accepting public comment since early December on Holly's proposal to modernize its refinery and increase its processing capacity in West Bountiful from 31,000 barrels of oil a day to 60,000 barrels a day.

Under the proposed modification, the refinery wants to add a crude processing unit and implement technology that will allow it to process crude that is produced in Utah's Uinta Basin.

The state Division of Air Quality said the crude has a lower sulfur content than other oil and that it will be processed with equipment that will result in emission reductions for PM2.5, or very fine particulate pollution. Other pollutants such as volatile organic compounds and sulfur dioxide will be significantly reduced, according to Utah air quality regulators, under the modification proposal submitted to the state.

"In this particular case, the modifications result in a benefit to the air shed," said Martin Gray, the division's new source permitting manage. "There is a reduction in the criteria pollutants that contribute to our winter-time haze pollution." On the flip side, emissions would be increased for carbon monoxide.

With cold settling in, snow on the ground and a high pressure system parked over much of the state, some critics are wondering why the state would contemplate any sort of modification that includes increasing production capacity, and therefore some type of pollutant.

"Their permit says nothing about the about the expected 350 daily truck trips to and from the refinery," said Terry Marasco, with the Utah Clean Air Alliance. "The pollution from this permit is in addition to the increased pollution from the Tesoro expansion ... added to the expansion at Kennecott and on and on and on. The results are what you are breathing this week."

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