Irwin Thomas Gravel Mine - City of Longmont Skip to main content

Overview of the Irwin Thomas Gravel Mine Operation

 

Map Location of Irwin Thomas PropertyA gravel mining operation is expected to begin in March 2023 on the property located both north and south of Ken Pratt Boulevard, east of the Costco development. The gravel mine was permitted by the Boulder County Commissioners in 2003 and was annexed into Longmont in 2018. The gravel mine operation is permitted by the City as a PUD (Planned Unit Development). The PUD was amended in January 2022 to accommodate for the development of Costco east of Martin Street. Below is more information related to the gravel mine operation, including conditions and requirements to protect the nearby residents.

 

FAQs

 

Where is the gravel mine located?

  • A gravel mine was permitted by Boulder County in 2002 to mine a 295.6-acre parcel of land both north and south of Ken Pratt Boulevard, west of 119th Street, north of Quail Road and east of the Costco development.

 

When was the gravel mine approved?

  • The permit was approved and signed in 2003 under a development agreement with Boulder County, which gave them a vested property right for the gravel mining.
  • The property owner submitted an application for annexation into the City in 2015 and desired to maintain their gravel mining permit. They requested approval of a PUD Plan, which mirrored the mining plan and conditions of approval as set forth in Boulder County. The PUD Plan was amended in 2022 to reflect changes to the Irwin Thomas site as a result of the Costco development.

 

Was there a public notification process?

  • A neighborhood meeting was held in January 2016 and public hearings were held with Planning & Zoning Commission in January 2017 and City Council in September 2017. Notification to all property owners within a 1,000-foot radius was mailed out and signs were posted on the property. The developers of the housing projects in Harvest Junction Village were also notified of the neighborhood meetings and public hearings.
  • There is no public input/community involvement at this time. Concerns may be stated and staff are available to answer questions, but final plans have been approved.

 

Are there any protections for nearby residents?

  • The PUD Plan contains a page dedicated to conditions of approval related to traffic, noise, dust, lighting, etc.
  • One of the conditions of the PUD was that they are required to construct a berm wall on the west and south sides of the property to provide a protective barrier/buffer from the adjacent land uses. A detail sheet for the berm can be found on the right side of the map. No mining operations can commence until the berms are constructed.

 

Can I see a copy of the approved plan?

  • The Planning & Zoning Commission approved the PUD Plan in January 2017 at a public hearing on the condition that it would not be final-approved until City Council approved annexation of the property.
  • The PUD Plan is for gravel mining and reclamation only. All materials must be hauled off-site to a processing plant. No processing will take place at this site.
  • The City Council approved annexation of the property in September 2017 but the annexation ordinance was not recorded with the county clerk (and thus finalizing the annexation) until February 2018.
  • A PUD Amendment was approved by City Council in January 2022 modifying the mining area to accommodate for the Costco development. This is the most recent approved modification to the proposed scope of work.

 

Can you tell me more about the mining process?

  • Holcim Group has indicated that the mining process can take up to 6 years and the length of time depends on a number of factors, including market conditions and demand.
  • The mining pods will be mined consecutively, so that only one pod or portions of two pods and the processing site are disturbed during any phase of mining.

 

Conditions of the Project – Updated January 2022

 

  1. The Development consists of open mining and reclamation on approximately 120.5 acres of a 346 acre area on the Irwin Thomas property located at the northwest intersection of Quail Road and North 119th Street.
  2. Roads/Parking – The following roads shall serve the Development subject to the conditions and limitations as further set forth: N. 119th Street; Quicksilver Rd; and State Highway 119. Access to the site from State Highway 119 is shown on Sheet 269 of the Colorado Department of Transportation’s construction drawings for State Highway 119, prepared by Carter and Burgess, and revised on March 13, 2002. This access may be revised only upon the approval of the Colorado Department of Transportation and the City of Longmont. The use of Quicksilver Road is subject to approvals of the City of Longmont and Boulder County. The Developer shall obtain an access permit from the City of Longmont before utilizing North 119th Street for truck hauling. The Developer shall provide written consent from the Colorado Department of Transportation before conducting any construction work within any portion of the State Highway 119 right-of-way. Employee parking will be located in a designated gravel parking area adjacent to the scale house. See note 14 for requirements regarding the St Vrain and Left Hand Creek riparian Setbacks.
  3. Landscaping/Reclamation – The Developer shall provide revegetation for the development in accordance with the City and Colorado Division of Reclamation, Mining and Safety (DRMS) approved mining and reclamation plans. This revegetation shall include the installation of a seeded temporary screening berm, on the western edge of the property between any mined areas and Harvest Moon Drive and along the southern limits of the mining to screen the activity from the existing homes along Quail Road. The berm and seeding shall be completed before any mining is commenced south of State Highway 119 as shown on the Mining Plan. The berm shall be removed at the completion of mining activities on the south side of HWY 119. Final reclamation of any City owned property to be reviewed and approved by the City. Any changes to the plans as presented for the City owned property to be coordinated with the mining operator.
  4. Signage – All signs for the Development shall comply with the applicable provisions of the Longmont Land Development Code. The Developer has posted one sign along N. 119th Street and one sign along Quail Road stating that mining will take place on the site in the future. The content, size, and location of the signs must be approved by the City of Longmont prior to installation.
  5. The Developer shall pay City of Longmont Transportation Investment Fees at the time of Building Permit.
  6. Enforcement – The City may conduct a periodic review of the Development as necessary to assure compliance with the Final Development Plan for Gravel Mining and Reclamation. This right includes the right to enter upon the property included within the Development at any time, without prior notice, to inspect for compliance with the terms of the PUD. All site visitors to the active mining site will be required to go through appropriate Mine Safety and Health Administration (MSHA) training, wear required safety equipment and check in at the scale house prior to entering the site.
  7. The proposed mining pods range in size from 6 to 19 acres and will be mined in the numbered sequence indicated on the PUD plan.
  8. The final reclamation plan includes five irregularly shaped ponds totaling about 73 acres with the area between the St. Vrain Creek and Burlington Northern Railroad consisting of about 25.5 acres of wetlands. The exact number and configuration of the ponds may vary based on the gravel resource and available fill material.
  9. The main access to site will be located on N. 119th Street, directly across from Quicksilver Road. No traffic will leave the site traveling south on N. 119th Street beyond Quicksilver Rd and trucks entering the site must not travel between Quail Road and Quicksilver Rd. There is a prohibition on truck hauling on Quail Road and south of Quicksilver Rd on North 119th Street. Access to the mining cells located north of St Vrain Creek will be via the existing easement and access road onto North 119th Street.
  10. If sustained winds exceed 30 MPH at mining sites, loading and hauling operations will cease until the wind speed drops below 30 MPH. Conveying, and drilling operations may continue. Wind speed shall be measured at the mine site. The applicant will utilize the following additional measures to manage dust during mining and reclamation of the property:
    1. Emissions from all material handling (i.e. removal, loading and hauling) will be controlled by watering unless natural moisture is sufficient to control emissions).
    2. On site haul roads will be watered as often as needed to control fugitive particulate emissions.
  11. Any ditch crossings or relocations shall be done only upon the consent of the ditch companies and in accordance with all applicable regulations.
  12. The Applicants shall obtain all applicable permits as required and necessary. This includes, but is not limited to: Floodplain Development permits, National Pollution Discharge Elimination System permits, Air Pollution Control Emission permits, Construction Materials Regular Operation (112) Reclamation permits, Water Discharge permits, City of Longmont Stormwater Construction Activity Permit and any well permits or temporary substitute supply plans required by the State Engineer.
  13. This use must comply with all applicable state and local noise standards and state and local fugitive dust standards.
  14. The St Vrain Creek and Left Hand Creek riparian setbacks shall be marked with permanent monuments on the ground for the duration of the mining period. No mining activities shall occur within this defined area. The applicants must reclaim all adjacent areas in accordance with the plans approved by the City before removing any monument.
  15. Outside storage, and the storage of fuel, oil, and grease, as well as the repair of equipment and machinery, are accessory uses to this approval, provided the applicants meet all applicable local, county, state and federal regulations. Accessory activities shall take place within active mining cell and will be relocated as mining and reclamation proceed. Accessory activities may take place between 7am and 7pm or dawn to dusk (whichever is more restrictive) Monday through Saturday. No activity is permitted on Sunday. Maintenance of equipment may take place before or after normal working hours if required to repair equipment necessary for operations (i.e. conveyor) or to respond to an emergency.
  16. The property will comply with the City of Longmont’s requirements for drainage.
  17. Development on the property shall comply with the City’s Flood Plain Regulations based on the best floodplain data available at the time of development.
  18. This approval recognizes the following: Mining of approximately 3.5 million tons of material; A total of 150 average daily trips to the site, not to exceed 200 trips per day; Accessory processing of sand and gravel including screening and stockpiling. The mining operator may install a portable screening plant in the bottom of an active mining cell to sort material prior to removal from the site.
  19. The Applicants shall mitigate adverse impacts on neighboring wells caused by de-watering or other mining operations that result in lower ground water levels outside of mining boundaries. To meet this requirement, the Applicants shall install piezometers adjacent to residential areas sufficient to determine the effect on adjoining properties. If mining operations cause a reduction by more than 10% in water quality or quantity, the Applicants shall provide replacement water equal to or better in quantity and quality to the original conditions. In fulfilling this condition, the Applicants shall be responsible for conducting industry recognized water quality/quantity analyses at least four times a year. The Applicants commit to monitor groundwater wells quarterly throughout the life of the mine.
  20. The mining pods will be mined one at a time so that only one pod or portions of two pods and the processing site are disturbed during any phase of mining. The mind portion of any mining pod in any phase shall be limited to that shown on the approved plan. If mining is underway in more than one pod at a time, the combined mining area shall not exceed 35 acres. For purposes of interpreting this condition, “combined mining area” shall mean any area that has been disturbed in preparation of mining, or in which mining is underway, or in which grading for reclamation for is underway. once grading of a reclaimed mining pod is completed it will no longer be considered as part of the combined mining area. Revegetation and weed management within reclaimed pods will be ongoing throughout the life of the mine.
  21. The Applicants shall obtain an access permit from the City of Longmont before using North 119th Street for any truck hauling. Before issuing the access permit, the City may determine what, if any, mitigation measures to North 119th Street and Quicksilver Road are necessary. Mitigation measures may include, but are not limited to, payment by the Applicants of a pro-rata share of the costs of any acceleration or deceleration lanes, pavement rehabilitation, traffic control devices, or other measures necessary to correct adverse impacts to the street. Any costs associated with determining the proper mitigation measures are the responsibility of the Applicants.
  22. The Applicants shall obtain written consent from the Burlington Northern Railroad before conducting any construction work within any portion of railroad right-of-way.
  23. The Applicants shall require all sand and gravel loads hauled from the site in any Applicant-owned or leased trucks, or by haulers under contract to the Applicants to be covered with tarps, to prevent fugitive dust and gravel from escaping during hauling.
  24. Mining operations and truck hauling are limited to Mondays through Fridays: during the period of daylight savings time the hours of operation shall be 7:00 a.m. to 7:00 p.m., and during the period of standard time the hours of operation shall be 7:00 a.m. to 7:00 p.m. or daylight to dark (whichever is more restrictive). On Saturdays, work is restricted to equipment maintenance, maintenance necessary to ensure compliance with required permits, and hauling. Hauling on Saturdays is restricted to the hours listed above and separate City staff approval. No work at the site can occur on Sundays.
  25. The applicant shall require all Applicant-owned or leased trucks and all trucks under contract to the Applicants to utilize “white noise” back up beepers as opposed to standard back up beepers. All mining and loading equipment associated with the mining and reclamation shall also utilize “white noise” back up beepers.
  26. Site access onto N. 119th Street and Mining operations shall not inhibit safe use of the St. Vrain Greenway unless approved by the City of Longmont. Per the existing MOU between the City and the gravel operator, the City will install a 6′ tall chain link fence 10′ to 15′ south of the St. Vrain Greenway trail to limit access from the trail into the mining site. Timing of the installation of the fence shall be coordinated with the operator to assure that the fence is in place when the operator is ready to begin mining the area north of HWY 119.
  27. All mining activities shall comply with the Memorandum of Understanding between the applicants, Aggregate Industries and the City of Longmont dated December 20, 2005.
  28. This PDP/FDP is conceptual in nature. Exact configuration of Mining and Reclamation may change subject to site conditions and material available for fill. Any changes will be coordinated with the landowner and the City of Longmont. Revisions to the mining and reclamation plan that do not require an amendment to the DRMS permit may be approved through the administrative Staff review process at the City of Longmont. The operator will submit any required Technical Revision to the DRMS.

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