AFS is proposing the Spur Amendment on AFS property located in Clear Creek County north and east of where U.S. Highway 6 intersects with Interstate 70. The Spur Amendment is an extension of the existing AFS Walstrum Quarry that has supplied aggregate construction materials for Colorado’s industrial, commercial, and residential uses since 1983.

Spur Amendment Overview Map. Click to view a larger version

The existing Walstrum Quarry permitted area covers 286 acres of land. The Spur Amendment adds 225 acres of quarry disturbance area and 239 acres of undisturbed area to serve as a buffer around the disturbance area.

The purpose of the Spur Amendment is to extend the life of the existing Walstrum Quarry operation to allow the facility to continue to meet the construction material needs of Clear Creek County, the Front Range, and surrounding areas well into the future. The Walstrum Quarry provides a significant amount of the Front Range’s aggregate supply. It is the only active aggregate supply in Clear Creek County and one of only four large-scale sources of hard-rock aggregate on the Front Range.

The name Spur Amendment is a nod to the mining and railroad history of the local area. In the 1870s, a 3-foot narrow gauge line was built through Clear Creek Canyon to Idaho Springs and up to Silver Plume to serve the mines in the area.

Safety is Our Priority

AFS promotes a safe culture for visitors, customers, contractors, and employees of the Walstrum Quarry. AFS adheres to stringent safety standards and training as required by the Mine Safety and Health Administration for operating quarries. At AFS, we are committed to developing and maintaining programs that meet and/or exceed all the requirements of the law.

Environmental Protection

AFS demonstrates an ongoing commitment to environmental responsibility through the way the Walstrum Quarry is operated. Water sprays, enclosures, sight berms, water trucks, and sweepers are used to minimize dust emissions from crushers and roads, and detention basins are used to protect water quality. AFS also uses the most advanced, environmentally friendly aggregate truck load-out system in the United States. This quicker, more accurate loading process results in shorter wait times and less truck idling. These methods will continue to be used with the Spur Amendment as part of AFS’ commitment to environmental stewardship.

The Spur Amendment is designed to minimize impacts on the environment and wildlife. Reclamation being performed concurrent with mining has produced valuable bighorn sheep habitat with high-quality native forage. Bighorn sheep favor steep terrain without trees, referred to as “escape terrain” that quarry reclamation produces. AFS will ensure environmental impacts are minimized through the use of mining best management practices and controls. Following mining, AFS will continue to implement their innovative revegetation practices that have helped achieve successful vegetation on reclaimed areas.

Several regulatory authorities will require permits for the Spur Amendment, including permits from the Colorado Department of Public Health & Environment; Colorado Division of Reclamation, Mining and Safety; Colorado Parks and Wildlife; and Clear Creek County. Permit reviews by these entities will ensure the Spur Amendment is being mined in accordance with industry best practices to minimize environmental impacts. Additional information on permitting can be found here.

Reclamation Plan

Restoration and Reclamation Activities in Progress Example

Reclamation and revegetation prevent erosion by effectively stabilizing the soils while improving the visual aesthetics of the previously mined area. Revegetation actively takes place under the guidance of reclamation specialists who regularly evaluate the conditions to improve the likelihood of success. Soil amendments are applied to address plant nutrient requirements and facilitate soil-water retention. AFS also tests new reclamation methods based on the latest advancements in reclamation science.

AFS will continue to reclaim disturbed lands on an ongoing basis as mining is completed in various areas of the Spur Amendment. AFS’ plans for reclamation of the Spur Amendment include four end uses:

1.Undisturbed land will continue to function as privately owned open space and wildlife habitat.

2.Reclaimed slopes and benches will function as privately owned natural resource areas.

3.Two areas of relatively flat land will be designated for commercial/industrial/ public gathering use, including the existing floor of the Walstrum Quarry where the processing plant is currently located. Views into the two commercial/ industrial/public gathering areas will be limited by the quarry design that utilizes ridges and hills to screen views of the quarry floor from the public right-of-way.

4.Two areas will be designated for future water storage reservoirs.

Facility Operations

The Walstrum Quarry processing plant and distribution facilities generally operate during daylight hours and maintenance occurs overnight. These hours of operation will not change as a result of the Spur Amendment. The Spur Amendment will also not make any changes in operations that would increase the average vehicle daily trips from what the Walstrum Quarry is currently allowed under its existing CDOT permit.

Homestead Parcel

Homestead Parcel

As part of the Spur Amendment, AFS desires to mitigate potential impacts caused by the larger quarry footprint by dedicating the approximately 18-acre parcel, aka, the Homestead Parcel of the Floyd Hill Meadow for land conservation. Plans for the conservation of the Homestead Parcel are in progress.

Homestead Parcel Location
Historical Railroad built through Clear Creek County to Idaho Springs (Source:

For additional information, or to provide questions and comments:
Contact Us
Call: 720-739-2053

We look forward to hearing from you.