Data / Mines / Colorado

Mines in Colorado: 314 open mines and MSHA citations

MSHA lists 314 open mines in Colorado, run by 181 operators and employing 4,039 people. Since January 1, 2022 its inspectors issued 9,636 citations and orders there with $8,870,477 in proposed penalties, and operators reported 540 injury or illness cases, 4 of them fatal. The operators with the most open mines are Oldcastle SW Group, Inc.; Arizona Materials; Martin Marietta Materials, Inc.. Data from MSHA, November 6, 2026.

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Open mines

314

Operators

181

Employees

4,039

Intermittent

140

Active

134

Temporarily Idled

28

NonProducing

8

New Mine

4

Mines run by individuals, counted and not listed

25

Citations and orders since January 1, 2022

9,636

Significant and substantial

1,406 (14.6%)

Closure orders

113

High negligence or reckless

888

Proposed penalties

$8,870,477

Amount paid so far

$6,701,412

Inspections

3,646

Inspector hours on site

58,342

Citations per inspection

2.64 (all mines 2.30)

Accident reports

576

Injury and illness cases

540

Fatalities

4

Latest MSHA record

November 5, 2026

Operators with the most open mines in Colorado

Ranked by open mines, then by citations. Sole proprietors and individuals are not listed.

Operators with the most citations in Colorado

Citations and orders issued since January 1, 2022 at their open mines here.

Mines with the most citations

Open mines, ranked by citations and orders since January 1, 2022.

Counties

Mines by kind

Main commodities

Citations and injury cases by year

Calendar years since 2022; 2026 runs to the date of the MSHA files.

Standards cited most at mines in Colorado

Sections of Title 30 of the Code of Federal Regulations named on the citations, with the part each belongs to.

Injury and illness cases at mines in Colorado

Accident reports by degree of injury, as the operator reported them to MSHA.

What the accident reports at mines in Colorado describe

Accident classification, as MSHA codes the circumstances that contributed most directly.

Equipment named in accident reports at mines in Colorado

Updated November 6, 2026. Read from US Department of Labor, Mine Safety and Health Administration (MSHA), Open Government Data Sets. US government work, public domain. Counts come from the MSHA files published on November 6, 2026. An open mine is one MSHA lists as Active, Intermittent, New Mine, Temporarily Idled or NonProducing; 13,673 were open that day. Citations, penalties, inspections and accident reports run from January 1, 2022. A citation is an inspector's allegation and an operator can contest it; the penalty is the amount MSHA first proposed, before any contest or settlement. An operator is the legal entity MSHA assesses, and a parent company is its controller. Mines run by sole proprietors or by individuals are counted in every total and are not named. This page uses MSHA data and is not endorsed or certified by MSHA. Free to reuse with credit to SpecStream under CC BY 4.0. Spot a wrong value? Write to [email protected] with the link to this page.