MINE DETAILS
Hermosa Mine
LOCATION
Mine location
1 of 1 mine with usable MSHA coordinates. Select a marker to open a mine.
Mine coordinates
- Hermosa Mine31.46306, -110.72500Open map ↗
Quarterly trends
2025 Q1 – 2026 Q4
Database snapshot · 2026-10-18. MSHA quarterly production and employment reports.
Coal production
0reported short tons
Hours worked
730,833reported employee hours
Tons per hour
0.00production ÷ 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 | 0 | 103,027 | 0.00 | 150 | 1/1 mines reporting |
| 2025 Q2 | 0 | 149,112 | 0.00 | 159 | 1/1 mines reporting |
| 2025 Q3 | 0 | 128,871 | 0.00 | 160 | 1/1 mines reporting |
| 2025 Q4 | 0 | 95,897 | 0.00 | 161 | 1/1 mines reporting |
| 2026 Q1 | 0 | 123,615 | 0.00 | 168 | 1/1 mines reporting |
| 2026 Q2 | 0 | 130,311 | 0.00 | 174 | 1/1 mines reporting |
| 2026 Q3 | — | — | — | — | No report |
| 2026 Q4 | — | — | — | — | No report |
Safety and enforcement
2025-01-01 – 2026-10-18
Violations
6510 significant & substantial (S&S)
Accident records
200 records classified as fatality
Proposed penalties · USD
57,449.0062 of 65 violations with amounts
On-site inspection hours
664.7521 inspections · 21 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 | 14 | 6 | 13,162.00 | 4 | 0 | 3 | 53.0 |
| 2025-Q2 | 4 | 1 | 1,051.00 | 2 | 0 | 2 | 86.0 |
| 2025-Q3 | 13 | 0 | 30,656.00 | 1 | 0 | 3 | 103.8 |
| 2025-Q4 | 6 | 0 | 2,550.00 | 2 | 0 | 1 | 76.5 |
| 2026-Q1 | 3 | 1 | 700.00 | 6 | 0 | 1 | 88.5 |
| 2026-Q2 | 12 | 1 | 4,386.00 | 3 | 0 | 2 | 145.0 |
| 2026-Q3 | 13 | 1 | 4,944.00 | 2 | 0 | 7 | 90.0 |
| 2026-Q4 * | 0 | 0 | — | 0 | 0 | 2 | 22.0 |
Most cited CFR sections
All violations issued in the selected period. Counts combine subsections.
Safety activity
HANDLING OF MATERIALS · NO DYS AWY FRM WRK,NO RSTR ACT
Accident narrative
A mechanic was working on a pump in the vent shaft drill connex, the mechanic bent over to pick up a bolt off the floor and hit their head on the metal bench causing a laceration. The mechanic received staples to close the laceration.
HANDLING OF MATERIALS · NO DYS AWY FRM WRK,NO RSTR ACT
Accident narrative
Employee was parking the forklift at Hermosa Main Shaft. After securing the equipment by placing the wheel chocks, the employee reported pain in their lower back. Employee was prescribed a muscle relaxant.
MACHINERY · DYS AWY FRM WRK & RESTRCTD ACT
Accident narrative
Employee was assisting with landing a tugger on the 3680 level. Two employees were pulling the tugger on to the level as it was lowered, two employees pulled from one side of the tugger and a third employee was pushing on the opposite side of the tugger. The tugger rolled over in the rigging, trapping and breaking the right arm of the employee between the tugger and the rigging.
SLIP OR FALL OF PERSON · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
Employee slipped and fell on their left knee while pouring a concrete slab. Injury was diagnosed as a sprain, and the employee was prescribed anti-inflammatory medication.
HOISTING · ACCIDENT ONLY
Accident narrative
A programming issue resulted in the temporary suspension of all hoisting operations at the Main Shaft.
HANDTOOLS (NONPOWERED) · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
The injured employee was attempting to remove an O-ring seal while repairing a jackleg. The pick that the employee was using to remove the O-ring slipped and punctured the thumb on the employees gloved Left hand. The puncture became infected, incisions were made in the thumb in order to clean the wound, the employee also has been receiving IV antibiotics.
HOISTING · ACCIDENT ONLY
Accident narrative
At approximately 12:54 am, an electrical component failure caused a power outage at the shaft pad.
HOISTING · ACCIDENT ONLY
Accident narrative
At 09:28 hours, we experienced a loss of power from the generator plant, resulting in an immediate power outage at the shaft pad.
HOISTING · ACCIDENT ONLY
Accident narrative
At approximately 9:30 am, an electrical component failure caused a power outage at the shaft pad.
HOISTING · ACCIDENT ONLY
Accident narrative
At 2:43pm on 3/8/2026 both hoists lost power. 12 miners were working in the vent shaft, 7 miners were working in the main shaft. Power was re-established to the vent shaft at 3:31PM. Power was re-established to the main shaft at 3:45. No injuries sustained due to loss of power.
MACHINERY · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
While the employee was cutting unistrut with a handheld band saw the saw unexpectedly shifted and contacted their left index finger resulting in a laceration. The employee received two stitches.
HANDLING OF MATERIALS · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
Employee noticed a lump above their belly button. After being seen at urgent care the employee was diagnosed with an umbilical hernia.
HOISTING · ACCIDENT ONLY
Accident narrative
An unanticipated power disruption occurred on the Shaft Pad, impacting both the Main Shaft and Ventilation Shaft operations.
HANDLING OF MATERIALS · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
While assisting to replace a pulley on the batch plant, an employee strained their back. The employee was holding the pulley in place with both arms above their head, while another employee secured it in place. Once they finished, the employee began to notice middle and lower back pain. The employee immediately reported it to supervision.
SLIP OR FALL OF PERSON · DAYS AWAY FROM WORK ONLY
Accident narrative
Water truck driver was discovered to be injured by another miner at the water tower. The injured driver didn't remember how EE was injured, and there were no witnesses. It's suspected the driver either fell from ground level or off the rear access ladder of the truck. The second scenario is believed to be more likely due to the nature and severity of the drivers injuries.
SLIP OR FALL OF PERSON · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
While dismounting a Caterpillar D6 Dozer on the right side, miner lost EE's grip on the handhold and fell onto the right u-frame support beam resulting in three fractured ribs.
HANDLING OF MATERIALS · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
While an employee was placing the shackle of the man basket onto the hook of the 1300 crane for the daily load test, the hook spun, pinching the fingertip of the middle finger of the employee's right hand. This caused bruising and bleeding.
HANDLING OF MATERIALS · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
During the process of installing concrete metal decking at the Main Shaft muck bin, the IP had a hold of one with both hands. When the IP began to move, the metal slipped from their hand right ring finger.
SLIP OR FALL OF PERSON · DAYS RESTRICTED ACTIVITY ONLY
Accident narrative
While installing services in the Vent Shaft an employee (EE) was on an extension ladder, tightening the band on a section of Shaft Vent Ducting. The EE detached their lanyard from the anchor above and proceeded to descend the ladder. While descending the EE lost their footing and fell approximately 10 feet. The EE landed on their right side resulting in injuries.
HANDLING OF MATERIALS · NO DYS AWY FRM WRK,NO RSTR ACT
Accident narrative
Two electricians were installing a metal stand (approx. 300 LBS.) adjacent to the surface shaft ventilation fans. While the electrical stand was being positioned to secure on the ventilation pad, the load became unstable. The electricians attempted to stabilize the stand but were unable to prevent it from falling. When the rack fell, the employee's right pinky finger was lacerated.
Safety sources and definitions
MSHA Violations (issue date), Accidents (accident date), and Inspections (begin date). Snapshot 2026-10-18.
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.
South32controlsSouth32 Hermosa Inc.operatesHermosa Mine
msha-controller-operator-history · controller/operator co-tenure derived on mine 0203398Arizona Mining InccontrolsSouth32 Hermosa Inc.operatesHermosa Mine
msha-controller-operator-history · controller/operator co-tenure derived on mine 0203398Other 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.
Accidents and injuries
46 historical accident/injury rows; 0 coded fatalities and 510 lost days across the published record.
accidentsmine-production-quarterlyViolations and penalties
193 violation rows across the full record; 26 carry an S&S flag and $93,799 appears in current assessed amounts.
inspectionsviolationsassessed-violationsorders-107aOccupational health samples
27 personal. 2 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.
personal-health-samplesQuarterly production and employment
130K employee hours and 174 summed average employees across reported subunits in the latest published quarter.
mine-production-quarterlymine-production-yearlyContests, conferences and decisions
22 contested-violation rows, 22 civil-penalty docket/decision rows, and 17 conference records linked by issuance number.
conferencescontested-violationscivil-penalty-dockets-decisionsContractors
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.
contractor-production-quarterlycontractor-production-yearlyaccidentsviolationsInspections
65 inspection events and 3K published inspection hours across the historical record.
inspectionsviolationsHEALTH SAMPLING
Silica and quartz
Coal quartz, metal/nonmetal personal samples and area samples. Snapshot Oct 18, 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.
This can mean the operation is non-coal, inactive for the annual period, or outside the EIA-7A reporting population.
RECENT PUBLIC RECORDS
Recent violations and samples
Latest records retained for inspection; aggregates above use the full source history.
Coal dust, noise and other contaminants. Silica records above ↑
SOURCE COVERAGE
Reporting dates and coverage
15 datasets contain linked records. Missing datasets are listed below.
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.