Granite Construction to operate proposed Parleys Canyon pit, now called I-80 South Quarry

Massive limestone operation faces intense opposition and tough approval process.

(Rick Egan | The Salt Lake Tribune) A Parleys Canyon property owner has proposed operating a massive limestone quarry on a 634-acre parcel at this spot in Parleys Canyon, on Wednesday, Dec. 8, 2021.

The proponent of a controversial limestone quarry in Parleys Canyon has named Granite Construction as its operator, according to a website launched this week to promote the project that has drawn intense opposition from nearby homeowners, elected officials and environmentalists.

The project, confusingly called the Silver Mine, has also been renamed I-80 South Quarry in reference to the interstate freeway running by it and to distinguish it from the Harper’s Quarry on the north side of the freeway, as well as to dispel any notion that the project would extract precious metals.

Late last year, a newly formed LLC called Tree Farm filed parallel permit applications with the Utah Division of Oil, Gas and Mining, or DOGM, to conduct a small mining operation and another proposing a large one. In response to the surprise filings, homeowners in neighboring Mt. Aire Canyon organized an opposition campaign that has drawn thousands of supporters, including Salt Lake County Mayor Jenny Wilson, who believe Parleys Canyon is no place for another massive pit and industrial operation.

(Rick Egan | The Salt Lake Tribune) Mt. Aire Canyon resident Joe Reimann, points out some of the areas that may be affected by the proposed open-pit limestone quarry, in Parleys Canyon, on Wednesday, December 8, 2021.

The new website claims the quarry and crushing plant can be developed and operated without harming the environment, wildlife, public safety or recreation and without violating air quality standards. Utah’s growth will require vast quantities of aggregates used in construction and it would make the most sense, both environmentally and economically, to produce this material close to where it would be used, the website argues.

When we talk about housing affordability, when we talk about road affordability and infrastructure affordability, all of the materials that make up those things are a big driver in the costs ultimately for those things. If we don’t have any supply, the costs are way up,” said Matt Lusty, a Utah publicist hired by Tree Farm.

Parleys is an excellent location for the mine because of its proximity to construction sites.

“The further away we build those things, to [transport] them to where they need to be driven to, the cost increases,” Lusty said. “So it has a big cost on the consumer. And then not to mention, you have trucks driving longer distances, which obviously isn’t good for air quality. It’s not good for the environment. "

He said the quarry’s production would put up to 140 trucks a day on Interstate 80, but that would result in a tiny increase of traffic on the busy freeway, which sees, on average, 60,000 vehicles a day.

Last year Tree Farm, a Utah company registered to developer Jesse Lassley, acquired the 634-acre parcel where the quarry would be excavated on the northeast flank of Grandeur Peak. In his permit application, Lassley, who sold his home in Mt. Aire Canyon about a year before news of the quarry broke last November, proposed a pit that would produce up to 2 million tons of limestone a year.

The site of the proposed quarry in Parleys Canyon. (Christopher Cherrington | The Salt Lake Tribune)

Over time the pit’s floor would expand to 153 acres, making it one of Utah’s largest and most productive quarries inside an already congested canyon. Until this week, Tree Farm declined to identify the quarry’s would-be operator. Granite is headquartered in Watsonville, Calif., and operates six plants in Utah.

Tree Farm also owns a 50% stake in the Harper quarry, which is operated by the Kilgore Companies, another major aggregate producer with several operations in Utah. Lusty said he is not aware whether the existing and proposed quarries in Parleys Canyon, which are hardly a mile apart, are connected.

The website claimed that growth in Salt Lake City region will require 258 million tons of aggregates over the next 20 years.

One potential customer for the quarry’s output could be the even more controversial Utah Lake Restoration Project, a proposal to build at least 18,000 acres of artificial islands on Utah Lake. Backers have disclosed that the islands and interconnecting causeways expect to use $357 million worth of crushed stone. At today’s prices of Utah-quarried rock, that kind of spending would buy nearly 50 million tons.

Almost immediately into the permitting process, DOGM director John Baza rejected Tree Farm’s application for a small mine, reasoning that the company’s true intent is to develop a large mine, as opposed to the maximum 20-acre footprint allowed under a small-mine permit.

Tree Farm disputed that decision, and the Board of Oil, Gas and Mining will hear the appeal at its Feb. 23 meeting. Salt Lake City and Millcreek, the two cities closest to the quarry, have intervened in the case, arguing Tree Farm should not be allowed to circumvent the state’s more robust permitting procedure for large mines. Officials from both cities fear the quarry’s dust would degrade drinking water supplies and air quality.

Salt Lake City, which provides water to 360,000 residents, including many outside its boundaries, holds extensive water rights in the canyon and has made it clear it would not provide water to the mine. In a declaration, public works director Laura Briefer said the quarry would make it difficult for the city to meet its obligations under federal law to safeguard its water resources.

Heightening Briefer’s concerns is the quarry proponents’ limited access to water, which would be needed for suppressing dust.

“This leads me to the conclusion that any water right possessed by the Tree Farms … appear to be inadequate to meet the operational demands of the mine, particularly since water quality issues and dust emissions associated with the proposed mine would be reliant on a reliable source of water to mitigate,” she wrote.

In the meantime, Salt Lake County officials have embarked on a process to amend the county’s zoning ordinances to prohibit new quarries from being developed in the Wasatch foothills. That effort could run afoul of a law passed in 2019 prohibiting counties from restricting the extraction of aggregate and other “critical infrastructure materials.”

Granite executives did not make themselves available for an interview, but CEO Kyle Larkin did offer a statement through Lusty.

“This project will serve Utahns for years to come,” the statement said, “and Granite is dedicated to operating with industry-leading practices that protect the environment and match what citizens of the ‘best-managed state’ have come to expect in their businesses.”