SALT LAKE CITY — Utah's land, air and water were besieged by a number of challenges in 2015, with state regulators tackling all manner of concerns, such as response to the 3-million gallon Gold King Mine spill and continued monitoring of a migrating groundwater plume on Salt Lake City's east bench.

In its annual State of the Environment report, the Utah Department of Environmental Quality took a look back on the milestones accomplished over the past 12 months and the problems that are likely to persist.

With Utah's population expected to nearly double in the next 34 years, safeguarding a clean water supply, boosting air quality and cleaning up a legacy of contamination are top concerns, according to Alan Matheson, the department's executive director.

"One of the defining characteristics of Utah is our stewardship ethic," Matheson said, "a drive to leave the world a better place for those who follow."

Air quality

An infusion of money from the Utah Legislature helped regulators leverage more than $7 million in new funding to carry out 14 research projects. Scientists looked at the Great Salt Lake's role in the formation of ozone, the contribution of wood smoke to the wintertime fine particulate pollution problem and how to better predict emissions from oil and gas operations in the Uintah Basin, among other things.

The department was also given new money to help people upgrade equipment that has emissions, be it lawnmowers, snowblowers or even old school buses. Through the lawn mower exchange program, the department provided 388 electric lawnmowers at a discounted price and offered other incentives for people to trade in their gas mowers. The result was the equivalent of removing 120 passenger cars from Utah roads.

Utah also grappled with new federal mandates on ozone limits and regulations dealing with power plant emissions, in addition to developing a plan awaiting federal action to deal with regional haze impacting national parks.

Cleaning the water

In 2015, the state Division of Water Quality began requiring wastewater treatment plants to begin monitoring for phosphorus and nitrogen. An excess of these nutrients threatens to impair waterways, ruining high-quality fishing and compromising the outdoor recreation experience by creating algae blooms that cloud the water.

In the summer of 2015, state water quality regulators had to close Salem Pond, Payson Lake and Blackridge Reservoir due to toxic algae blooms and issue a public health advisory for the Lindon Marina at Utah Lake.

That same year, the division teamed up with the Utah Lake Commission and the Utah Division of Parks and Recreation for the first phase of an extensive study to better understand nutrient pollution and its impacts at Utah Lake.

Protecting the land

The year 2015 marked a significant turn in the history of the former 446-acre Midvale smelter slag site, which was removed from the EPA's National Priorities List as a Superfund site. What has now become Bingham Junction generates $92 million in employee income each year, with a variety of businesses, office space and a supermarket.

The department also obtained funding from the U.S. Environmental Protection Agency to further its plans for the Meadowbrook industrial area straddling South Salt Lake and Murray. The goal is to have a transit oriented station, neighborhood retail, high-density housing and open space.

The agency continues to wrangle the issue of depleted uranium, the byproduct of the uranium enrichment process that has critics hot over its potential storage in the western desert of Tooele County.

Depleted uranium, while classified as low level radioactive waste, grows hotter over time, leading to fears its shallow burial in the desert will be insufficient to protect public health.

The Utah Department of Environmental Quality hired its own consultants to review a lengthy site-specific performance assessment done by EnergySolutions on disposal considerations. The separate review, a safety evaluation, was released earlier this year, with additional conditions recommended. Both company and agency remain in the negotiating stage.

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