MINE DETAILS
Glenrock Mine 01
MSHA MINE ID4801891
LOCATION
Mine location
1 of 1 mine with usable MSHA coordinates. Select a marker to open a mine.
Mine coordinates
- Glenrock Mine 0142.85111, -105.83250Open map ↗
Quarterly trends
2025 Q1 – 2026 Q4
Database snapshot · 2026-10-17. MSHA quarterly production and employment reports.
Coal production
—reported short tons
Hours worked
—reported employee hours
Tons per hour
—production ÷ hours worked
Missing values appear as —. Totals use available reports. Tons per hour requires production and hours for the same quarters and a nonzero hours total. * Striped bars mark partial mine coverage or an incomplete quarter. See the table for coverage.
Quarterly data and reporting coverage
| Quarter | Coal (short tons) | Hours worked | Tons / hour | Avg. employees | Coverage |
|---|---|---|---|---|---|
| 2025 Q1 | — | — | — | — | No report |
| 2025 Q2 | — | — | — | — | No report |
| 2025 Q3 | — | — | — | — | No report |
| 2025 Q4 | — | — | — | — | No report |
| 2026 Q1 | — | — | — | — | No report |
| 2026 Q2 | — | — | — | — | No report |
| 2026 Q3 | — | — | — | — | No report |
| 2026 Q4 | — | — | — | — | No report |
Safety and enforcement
2025-01-01 – 2026-10-17
Violations
165 significant & substantial (S&S)
Accident records
40 records classified as fatality
Proposed penalties · USD
10,866.0016 of 16 violations with amounts
On-site inspection hours
91.007 inspections · 7 with hours
Counts are published records, including contractor records. * The quarter was incomplete at the snapshot date; recent counts may rise as reports arrive. — means no reported amount or hours. Portfolio totals use current membership.
Quarterly safety data
| Quarter | Violations | S&S | Proposed USD | Accident records | Fatality records | Inspections | On-site hours |
|---|---|---|---|---|---|---|---|
| 2025-Q1 | 6 | 2 | 8,928.00 | 1 | 0 | 2 | 37.5 |
| 2025-Q2 | 0 | 0 | — | 0 | 0 | 0 | — |
| 2025-Q3 | 4 | 2 | 957.00 | 1 | 0 | 2 | 27.0 |
| 2025-Q4 | 4 | 1 | 679.00 | 1 | 0 | 1 | 15.5 |
| 2026-Q1 | 0 | 0 | — | 1 | 0 | 0 | — |
| 2026-Q2 | 1 | 0 | 151.00 | 0 | 0 | 1 | 11.0 |
| 2026-Q3 | 1 | 0 | 151.00 | 0 | 0 | 1 | 0.0 |
| 2026-Q4 * | 0 | 0 | — | 0 | 0 | 0 | — |
Most cited CFR sections
All violations issued in the selected period. Counts combine subsections.
Safety activity
Compliance Follow-up Inspection · 0.0 on-site hours
50.20-1 · $151.00 proposed
56.14100(c) · $151.00 proposed
Regular Safety and Health Inspection · 11.0 on-site hours
STEPPING OR KNEELING ON OBJECT · NO DYS AWY FRM WRK,NO RSTR ACT
Accident narrative
Employee stepped on a nail. puncturing through EE's left boot into EE's left big toe.
MACHINERY · NO DYS AWY FRM WRK,NO RSTR ACT
Accident narrative
Employee was welding wear iron on an excavator bucket when a wind shift reduced ventilation, leading to fume inhalation. The employee reported shortness of breath and chest pressure and received first aid on site before being transported to the ER. The employee was released the same day, cleared to return to work the next day, and diagnosed with airway irritation.
56.14109 · S&S · $226.00 proposed
Regular Safety and Health Inspection · 15.5 on-site hours
56.14132(a) · $151.00 proposed
56.14206(b) · $151.00 proposed
56.3430 · $151.00 proposed
56.9101 · S&S · $151.00 proposed
56.11001 · S&S · $504.00 proposed
103 (g) Written Notification Hazard Complaint Inspectio · 11.5 on-site hours
MACHINERY · DAYS AWAY FROM WORK ONLY
Accident narrative
Employee was Operating a haul truck being loaded by an excavator. Employee stated that the Excavator struck the haul truck on the back and caused an injury to Employees Neck/Back. Employee refused first aid and or urgent care. Employee later turned in medical paperwork to MSHA.
50.30(a) · $151.00 proposed
Regular Safety and Health Inspection · 15.5 on-site hours
56.4201(a)(1) · $151.00 proposed
50.30(a) · $151.00 proposed
Spot Inspection · 21.0 on-site hours
56.12017 · S&S · $165.00 proposed
56.12018 · $151.00 proposed
50.10(b) · $7,555.00 proposed
56.14105 · S&S · $755.00 proposed
56.14112(b) · $151.00 proposed
Safety sources and definitions
MSHA Violations (issue date), Accidents (accident date), and Inspections (begin date). Snapshot 2026-10-17.
Counts describe published rows, including contractor records; accident records are not distinct incidents or numbers of people injured.
Zero means no matching records in the imported sources, not proof of no events. Historical coverage differs by source; absence before a source begins reporting is not a zero incident rate. Invalid or absent dates and records after the snapshot are excluded.
S&S means SIG_SUB=Y. Fatality records use DEGREE_INJURY_CD=01. Proposed penalties are not final assessed or paid amounts; missing dollar values are omitted.
Inspection hours are SUM_TOTAL_ON_SITE_HOURS attributed to the inspection start date, without supervisor/trainee hours. Missing hours are omitted; a started inspection may still be open.
Portfolio totals use current mine membership, including events before the current owner or operator's tenure.
CFR headings link to the current Title 30 index; they are not historical legal determinations.
OWNERSHIP
Operator and controller history
Current ownership comes from MSHA Mines. Historical start and end dates come from MSHA Controller and Operator History.
—
Founders of PRP LLC et alcontrolsPowder River Proppants, LLCoperatesGlenrock Mine 01
msha-controller-operator-history · controller/operator co-tenure derived on mine 4801891—
BGD LLC et alcontrolsPowder River Proppants, LLCoperatesGlenrock Mine 01
msha-controller-operator-history · controller/operator co-tenure derived on mine 4801891Other historical summaries · source-specific periods
RECORD SUMMARY
Production, safety and enforcement
These summaries use the periods stated on each card, independently of the reporting period above.
01 / SAFETYwatch
Accidents and injuries
4 historical accident/injury rows; 0 coded fatalities and 326 lost days across the published record.
ACCIDENT + INJURY RECORD4 since 2021
accidentsmine-production-quarterly02 / COMPLIANCEwatch
Violations and penalties
20 violation rows across the full record; 5 carry an S&S flag and $11,454 appears in current assessed amounts.
ENFORCEMENT ACTIVITY20 since 2021
inspectionsviolationsassessed-violationsorders-107a03 / HEALTHcontext
Occupational health samples
5 personal. 0 personal-sample rows have a published C/E ratio above 1; 0 noise rows have an action-level or PEL dose above 100%. These are separate measures, not a silica exceedance count. Silica results and sample status are shown separately.
OCCUPATIONAL EXPOSURE5 samples
personal-health-samples04 / PRODUCTIONcontext
Quarterly production and employment
The source remains registered, but no mine-keyed quarterly production row was published.
NO CURRENT QUARTERNo published quarter
mine-production-quarterlymine-production-yearly05 / LEGALwatch
Contests, conferences and decisions
6 contested-violation rows, 6 civil-penalty docket/decision rows, and 3 conference records linked by issuance number.
POST-ISSUANCE LIFECYCLE15 linked rows
conferencescontested-violationscivil-penalty-dockets-decisions06 / CONTRACTORScontext
Contractors
Contractors are linked through this mine’s violation or accident records. Their production and hours cover all their operations, so they are not included in this mine’s totals.
ENTITY-LEVEL CONTEXT1 linked entities
contractor-production-quarterlycontractor-production-yearlyaccidentsviolations07 / INSPECTIONScontext
Inspections
8 inspection events and 262 published inspection hours across the historical record.
OVERSIGHT COVERAGE8 since 2021
inspectionsviolationsHEALTH SAMPLING
Silica and quartz
Coal quartz, metal/nonmetal personal samples and area samples. Snapshot Oct 17, 2026. 2 silica records across the mine’s published history.
Personal silica samples · concentration / limit
Quarterly mean · published C/E ratio
— No eligible measurements. * Quarter in progress. Means describe the available samples, not average exposure across the mine.
Quartz % is the sample’s quartz content; µg/m³ is its reported concentration. Personal C/E is the ratio to the limit published with that sample. Personal and area concentration units and void status are not specified in those source files.
| Date / sample | Dataset / analyte | Occupation / area | Measurement | Sample status | Published action |
|---|---|---|---|---|---|
| No silica records match these filters. Missing samples do not establish safe conditions. | |||||
Sources and interpretation
- Coal means use numeric concentrations from samples marked not voided, excluding control/invalid sample types and dates after the snapshot. Missing values remain null; reported zeroes remain zero.
- Quarterly means describe available samples, not mine-wide or worker-average exposure. Quarters with no eligible measurements remain empty; the current quarter is partial.
- Personal C/E is MSHA's published concentration-to-limit ratio. A value above 1 is not by itself a citation or a determination under the 2024 silica rule. Personal and area files do not publish a void-status field.
- Area records include bulk-dust analyses and are kept separate from personal exposure results. Their concentration units are not specified in the source dictionary.
- Missing samples do not establish safe conditions. Coal quartz percentage and concentration are separate measures. No compliance threshold is inferred for coal samples.
Coal quartz field definitions ↗Metal/nonmetal personal field definitions ↗Metal/nonmetal area field definitions ↗
EIA + TITLE 30
EIA production and cited regulations
EIA annual figures are reported separately from MSHA. Regulation links use the current eCFR snapshot.
Not present in the 2024 EIA coal workbook.
This can mean the operation is non-coal, inactive for the annual period, or outside the EIA-7A reporting population.
30 CFR 50.20-1General instructions for completing MSHA Form 7000-1.1 recent row ↗30 CFR 56.14100Safety defects; examination, correction and records.1 recent row ↗30 CFR 56.14109Unguarded conveyors with adjacent travelways.1 recent row ↗30 CFR 56.14132Horns and backup alarms.1 recent row ↗30 CFR 56.14206Securing movable parts.1 recent row ↗30 CFR 56.3430Activity between machinery or equipment and the highwall or bank.1 recent row ↗30 CFR 56.9101Operating speeds and control of equipment.1 recent row ↗30 CFR 56.11001Safe access.1 recent row ↗
RECENT PUBLIC RECORDS
Recent violations and samples
Latest records retained for inspection; aggregates above use the full source history.
973263250.20-1Citation
503353656.14100(c)Citation
503371456.14109S&S
503371356.14132(a)Citation
503371256.14206(b)Citation
503371156.3430Citation
973243656.9101S&S
973243556.11001S&S
Coal dust, noise and other contaminants. Silica records above ↑
Respirable dust, <.1mgLaborer, Bullgang
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgLaborer, Bullgang
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgLaborer, Bullgang
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
SOURCE COVERAGE
Reporting dates and coverage
14 datasets contain linked records. Missing datasets are listed below.
DATASETROWSWINDOWSTATUS
Accident, Injuries, and Illnessessafety · contractors4Mar 11, 2025—Jan 10, 2026mine-keyed
Addresses of Recordidentity · logistics1Nov 9, 2024—Nov 9, 2024mine-keyed
Assessed Violationscompliance · legal20Nov 13, 2024—Aug 3, 2026mine-keyed
Civil Penalty Dockets and Decisionscompliance · legal6Not published—Not publishedmine-keyed
Coal Dust Sampleshealth · safety—No published rowsabsent / not applicable
Conferencescompliance · legal3Mar 2, 2026—Mar 2, 2026mine-keyed
Contested Violationscompliance · legal6Sep 17, 2025—Oct 14, 2025mine-keyed
Contractor Employment and Production — Quarterlycontractors · production · safety63Not published—Not publishedentity-linked
Contractor Employment and Production — Yearlycontractors · production · safety17Not published—Not publishedentity-linked
Controller and Operator Historyidentity · compliance2Nov 8, 2024—Nov 8, 2024mine-keyed
Mine Employment and Production — Quarterlyproduction · safety · compliance—No published rowsabsent / not applicable
Mine Employment and Production — Yearlyproduction · safety · compliance6Not published—Not publishedmine-keyed
Inspectionssafety · compliance8Nov 12, 2024—Aug 3, 2026mine-keyed
Minesidentity · production · logistics1Not published—Not publishedmine-keyed
Metal and Nonmetal Area Sampleshealth · safety—No published rowsabsent / not applicable
Metal and Nonmetal Personal Health Sampleshealth · safety5Mar 19, 2025—Mar 19, 2025mine-keyed
Noise Sampleshealth · safety · equipment—No published rowsabsent / not applicable
Quartz Samples — Coalhealth · safety—No published rowsabsent / not applicable
Violationscompliance · safety · legal20Nov 13, 2024—Aug 3, 2026mine-keyed
107(a) Orders Issuedsafety · compliance—No published rowsabsent / not applicable
NOTES
Limitations
- Contractor production is entity-level and is never represented as mine-attributable.
- Missing rows can mean no event, publication delay, identity mismatch, or inapplicability.