How We All Benefit From Construction Aggregates

Every day, almost every person touches and benefits from construction aggregates. Aggregates are the literal foundation to vital, life-sustaining infrastructure across industries. Modern transportation, energy, housing, and water systems are not possible without an economic supply of aggregate. The United States utilizes more than 2 billion tons annually in the form of granite, limestone, trap rock and other materials. [i]

In the past decade, Utah’s population has grown at the fastest rate in the country, adding more than half a million residents in the last ten years.[ii] This population explosion has been concentrated in the areas near Salt Lake City, with Wasatch County growing by 48%, Utah County by 30%, and Salt Lake County by 15% over the decade. With annual per-capita aggregate demand around 9-10 metric tons,[iii] the rapidly growing Salt Lake City area will require 258 million tons of various aggregates over the next 20 years.[iv]

Failing to develop new, local aggregate sources will have serious consequences. Materials will need to be transported longer distances, increasing air emissions, road wear, and fuel use. Long-term importation of aggregates is not a sustainable practice.

Granite is one of the nation’s oldest and largest civil infrastructure contractors and construction materials producers. Active in Utah for decades, Granite operates quarries and other construction materials facilities throughout the state. Granite’s operations consistently win awards for safety and environmental excellence, and the company operates under a code of conduct that demands ethical behavior in all actions.    

[i] https://www.nssga.org/who-we-are/our-products

[ii] https://www.sltrib.com/news/2021/08/12/new-census-numbers-are/

[iii] https://www.usgs.gov/publications/sociocultural-dimensions-supply-and-demand-natural-aggregate-examples-mid-atlantic

[iv] https://gardner.utah.edu/demographics/population-projections/

The I-80 South Quarry FAQ

  • What will be mined at the I-80 South Quarry?

    The facility will produce limestone hard rock, sand, and gravel to supply construction aggregates for projects throughout Salt Lake and Summit Counties. These construction aggregates are typically used for residential, commercial, and transportation facility construction. Ninety percent (90%) of the aggregates mined from the Quarry will be used east of I-15.

  • Will operations at the I-80 South Quarry meet all federal, state, and local air quality standards in Parleys Canyon?

    Yes. Operations from the quarry will meet all Utah Department of Air Quality (DAQ) and Environmental Protection Agency (EPA) air quality standards. The quarry will include design and mitigation measures so that strict government standards will not be exceeded. Specific regulations have been established and implemented by state and federal agencies to mitigate impacts to air quality from mining, construction, and development operations. Granite will strictly adhere to local, state, and federal air quality requirements, as is required in new source review permitting. DAQ regulations for emissions will be closely monitored and mitigated as required. Granite will obtain an air quality approval order from DAQ, ensuring no detrimental impact to the surrounding public health and air quality and ensure that operations would meet National Ambient Air Quality Standards. Moreover, Granite will strive to reduce emissions beyond UDAQ and federal requirements.

    Q. What about fugitive dust pollution?

    A. Before operations commence at the site, Granite will develop and implement a regulation-compliant Fugitive Dust Control Plan, defining the necessary controls to mitigate fugitive dust emissions, managed by DAQ. These controls will include, but are not limited to:

    • Water application to establish/maintain stabilization of surface soils;

    • Water application to vehicle traffic areas in staging areas and unpaved roads;

    • Application of typical dust suppressants with the watering plan;

    • Vegetation on berms, stockpiles, and other disturbed areas;

    • Reduced vehicle speeds; and

    • Opacity tests conducted by trained and certified personnel to ensure compliance.

    Q. What type of dust mitigation will occur on the site?

    A. Examples of mitigating actions include:

    • Water sprayers on conveyor transfer points, crushers, and screens to reduce or even eliminate airborne dust at the points of origin;

    • Road dust controls, including paving, sweeping, watering unpaved roads, and other proven forms of suppression; and

    • Road track-out controls including continual sweeping, a tire wash, and paving haul road to highway on ramps.

    This list is not exhaustive but is representative of the types of control measures to be utilized. These control measures are approved by the DAQ and are proven as Best Available Control Technologies (BACT). Implemented control measures will be monitored by on-site employees and state regulators to ensure they meet the UDAQ requirements.

  • Will blasting cause rock fragments to leave the site or shake rocks loose off the site?

    No. Blasting is strictly regulated. The site is surrounded by a self-imposed buffer area, and blasting will occur in the interior of the project area.  Moreover, modern quarry blasting operations are developed through scientific processes and controlled by carefully developed blasting patterns and sequencing of the process. Granite will design the blasting techniques to follow national blasting and vibration regulations to ensure noise and vibrations from the project are less than recommended standards.[i]

    https://www.govinfo.gov/content/pkg/CFR-2012-title30-vol3/pdf/CFR-2012-title30-vol3-sec817-67.pdf

  • Will this impact the watershed?

    No. This quarry will not impact the watershed due to it being located below the water treatment plant.

    I heard we get our water from Parleys Canyon. Does this project pose a risk to SLC drinking water?

    No. Drinking water for SLC is collected more than 1.5 miles upstream from the proposed site and is piped to the city.[i] 

    Do these operations pose a risk to groundwater?

    No. Aggregate production does not pose a major risk to groundwater. Aggregate production consists of merely pulling native materials from the ground, crushing, screening, and blending.  No chemicals are ever used to process the rock and sand.

    What about the equipment used?  Does it pose a threat?

    No. The mining equipment is typical to the construction industry.  A Spill Prevention Control and Countermeasure Plan will be developed and implemented to reduce the risk of impacts from the small quantity of petroleum products used on site. 

  • What kind of impact will this project have on threatened or endangered species?

    A first-class renowned biologist was engaged to conduct an exhaustive survey of potential wildlife impacts on the site. The project area falls within the potential range of two threatened or endangered species, the Canada lynx (Lynx canadensis; threatened) and the Western Yellow-Billed Cuckoo (Coccyzus americanus; threatened). These species have not been observed on site. The Canada Lynx’s known habitat is a great distance from the project. The current environment in Parley’s Canyon represents a poor breeding/foraging habitat for the species, and thus future migration to the area is highly unlikely but will be monitored, nonetheless. In the second instance, the project completely lacks the type of riparian habitat preferred by the Western Yellow-Billed Cuckoo.

    Ongoing efforts will be made to ensure that no species are threatened or endangered by the mine.

  • Will operations at this site eliminate or prevent wildlands access for recreation?

    No. The project site is completely located on private property with no current public recreation access. Recreation in the canyon and on Grandeur Peak will be unaffected. We are even exploring new recreation access across its private property as a benefit to the public at the end of mine-life.

  • I heard the mine will add 140 semi-trucks per day to the traffic on I-80 – won’t this mine only make traffic worse?

    No. The Annual Average Daily Traffic on the relevant section of I-80 has a five-year average of nearly 60,000 vehicles per day.[i] The addition of 140 trucks per day represents a 0.23% increase, which is about an extra 2 trucks for every 1000 vehicles. Therefore, the traffic impact of the mine’s aggregate trucking operations is negligible.

    https://drive.google.com/file/d/1rDXm0ObugGR1zXgWUuVbzWHNt-Xs1xru/view

  • I’ve heard that all mines are toxic and dangerous, won’t this one be the same?

    No. In aggregate mining, no chemical processing is used.  There will be no waste dumps, leach pads, or hazardous stockpiles generated by the quarry operations. In addition, all the material that will be produced at the quarry is marketable and will be sold as basic construction materials, or it is used as part of the reclamation of the site. Some customers will use the materials for landscaping purposes. There are not any naturally occurring deleterious or acid-forming materials on the site, meaning there are no potential impacts related to toxic tailings or outflows associated with this project.

  • Once all the material is used up, won’t this leave a huge, ugly scar on the landscape?

    No. An extensive reclamation of the site will be performed. This will include the redistribution of stored topsoil and the seeding and vegetating of the area with desirable, native species. Additional public access for recreational uses is also being explored. Adequate bonding for reclamation, regulated by DAQ, will be put in place prior to mining.

  • No. The land that is proposed for the quarry is private. Parleys Canyon has been mined since the mid-1800s.

  • Aggregates are a vital natural resource. They are essential to our quality of life and needed to build and maintain all roads, bridges, ports, levees, homes, hospitals, schools and public and private construction. Historically, communities have relied on local supplies of aggregates as the most efficient and effective way to supply materials.

    Today, we mainly transport aggregates by truck but, because it is a high bulk, heavy weight commodity, it is very costly to transport long distances and distance adds to environmental impacts. By supporting and obtaining locally produced materials, a community can help reduce consumer costs (fuel and energy costs), and reduce environmental impacts (specifically air quality emissions and greenhouse gases).