MINE DETAILS
Boron Operations
MSHA MINE ID0400743
LOCATION
Mine location
1 of 1 mine with usable MSHA coordinates. Select a marker to open a mine.
Mine coordinates
- Boron Operations35.02222, -117.70333Open map ↗
Quarterly trends
2025 Q1 – 2026 Q4
Database snapshot · 2026-10-13. MSHA quarterly production and employment reports.
Coal production
0reported short tons
Hours worked
2,253,991reported 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 | 422,344 | 0.00 | 755 | 1/1 mines reporting |
| 2025 Q2 | 0 | 315,667 | 0.00 | 744 | 1/1 mines reporting |
| 2025 Q3 | 0 | 350,265 | 0.00 | 715 | 1/1 mines reporting |
| 2025 Q4 | 0 | 376,670 | 0.00 | 701 | 1/1 mines reporting |
| 2026 Q1 | 0 | 396,646 | 0.00 | 758 | 1/1 mines reporting |
| 2026 Q2 | 0 | 392,399 | 0.00 | 755 | 1/1 mines reporting |
| 2026 Q3 | — | — | — | — | No report |
| 2026 Q4 | — | — | — | — | No report |
Safety and enforcement
2025-01-01 – 2026-10-13
Violations
12431 significant & substantial (S&S)
Accident records
140 records classified as fatality
Proposed penalties · USD
158,458.00111 of 124 violations with amounts
On-site inspection hours
535.7527 inspections · 27 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 | 2 | 0 | 377.00 | 1 | 0 | 3 | 35.0 |
| 2025-Q2 | 29 | 8 | 16,055.00 | 4 | 0 | 5 | 133.3 |
| 2025-Q3 | 2 | 1 | 89,226.00 | 3 | 0 | 4 | 35.5 |
| 2025-Q4 | 43 | 6 | 25,848.00 | 4 | 0 | 2 | 131.5 |
| 2026-Q1 | 0 | 0 | — | 1 | 0 | 2 | 3.8 |
| 2026-Q2 | 4 | 2 | 6,825.00 | 0 | 0 | 3 | 26.5 |
| 2026-Q3 | 35 | 12 | 20,127.00 | 1 | 0 | 7 | 170.3 |
| 2026-Q4 * | 9 | 2 | — | 0 | 0 | 1 | 0.0 |
Most cited CFR sections
All violations issued in the selected period. Counts combine subsections.
Safety activity
56.14132(b)(1)(i) · S&S
56.4130(a)(3)
56.12004
56.14112(a)(1)
56.16001
56.20003(a) · S&S
56.11002
56.12006
Regular Safety and Health Inspection · 0.0 on-site hours
56.14107(a)
103 (g) Written Notification Hazard Complaint Inspectio · 3.0 on-site hours
56.14100(b)
Verbal Hazard Complaint Inspections · 13.8 on-site hours
Compliance Follow-up Inspection · 1.0 on-site hours
STRIKING OR BUMPING · DAYS AWAY FROM WORK ONLY
Accident narrative
While a worker was standing near a band saw roller stand. A 1-1/2 sch 40 pipe was resting on rollers. Another worker accidentally bumped the pipe. The pipe rolled off the stand and struck the worker's right foot, causing a contusion.
Compliance Follow-up Inspection · 3.0 on-site hours
Impoundment Spot Inspection · 3.0 on-site hours
56.12032 · $226.00 proposed
56.18002(a) · S&S · $3,184.00 proposed
56.16001 · S&S · $432.00 proposed
56.12004 · S&S · $1,431.00 proposed
56.12032 · S&S · $3,184.00 proposed
56.12032 · $193.00 proposed
56.20003(a) · $151.00 proposed
56.11002 · S&S · $3,184.00 proposed
Safety sources and definitions
MSHA Violations (issue date), Accidents (accident date), and Inspections (begin date). Snapshot 2026-10-13.
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.
—
Rio Tinto GroupcontrolsU S Borax IncoperatesBoron Operations
msha-controller-operator-history · controller/operator co-tenure derived on mine 0400743Other 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
346 historical accident/injury rows; 0 coded fatalities and 8,712 lost days across the published record.
ACCIDENT + INJURY RECORD46 since 2021
accidentsmine-production-quarterly02 / COMPLIANCEwatch
Violations and penalties
2,029 violation rows across the full record; 347 carry an S&S flag and $1,632,488 appears in current assessed amounts.
ENFORCEMENT ACTIVITY443 since 2021
inspectionsviolationsassessed-violationsorders-107a03 / HEALTHwatch
Occupational health samples
50 personal; 14 area. 1 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 EXPOSURE64 samples
personal-health-samplesarea-samples04 / PRODUCTIONcontext
Quarterly production and employment
392K employee hours and 755 summed average employees across reported subunits in the latest published quarter.
2026-Q20 tons
mine-production-quarterlymine-production-yearly05 / LEGALwatch
Contests, conferences and decisions
211 contested-violation rows, 211 civil-penalty docket/decision rows, and 91 conference records linked by issuance number.
POST-ISSUANCE LIFECYCLE513 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 CONTEXT60 linked entities
contractor-production-quarterlycontractor-production-yearlyaccidentsviolations07 / INSPECTIONScontext
Inspections
235 inspection events and 16K published inspection hours across the historical record.
OVERSIGHT COVERAGE57 since 2021
inspectionsviolationsHEALTH SAMPLING
Silica and quartz
Coal quartz, metal/nonmetal personal samples and area samples. Snapshot Oct 13, 2026. 3 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 56.14132Horns and backup alarms.1 recent row ↗30 CFR 56.4130Electric substations and liquid storage facilities.1 recent row ↗30 CFR 56.12004Electrical conductors.1 recent row ↗30 CFR 56.14112Construction and maintenance of guards.1 recent row ↗30 CFR 56.16001Stacking and storage of materials.1 recent row ↗30 CFR 56.20003Housekeeping.1 recent row ↗30 CFR 56.11002Handrails and toeboards.1 recent row ↗30 CFR 56.12006Distribution boxes.1 recent row ↗
RECENT PUBLIC RECORDS
Recent violations and samples
Latest records retained for inspection; aggregates above use the full source history.
516675056.14132(b)(1)(i)S&S
516608256.4130(a)(3)Citation
516674956.12004Citation
516674856.14112(a)(1)Citation
516632656.16001Citation
516534956.20003(a)S&S
516534856.11002Citation
516534756.12006Citation
Coal dust, noise and other contaminants. Silica records above ↑
Respirable dust, <.1mgLaborer, Bullgang
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Nuisance dust, total, <1% QtzBagging Operator
C/E: 00.00Concentration: 0000.00 · limit: 0010.00Source unit unspecified
Nuisance dust, total, <1% QtzHammer Mill Operator
C/E: 03.37Concentration: 0033.68 · limit: 0010.00Source unit unspecified
Nuisance dust, total, <1% QtzDry Screen Plant Operator
C/E: 00.21Concentration: 0002.13 · limit: 0010.00Source unit unspecified
Unlisted Particulate, total, <1% QtzTruck Driver
C/E: 00.00Concentration: 0000.31 · limit: 0000.00Source unit unspecified
Unlisted Particulate, total, <1% QtzTruck Driver
C/E: 00.00Concentration: 0000.22 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgTruck Driver
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Unlisted Particulate, respirable, <1% QtzUtility Man
C/E: 00.00Concentration: 0001.41 · limit: 0000.00Source unit unspecified
SOURCE COVERAGE
Reporting dates and coverage
16 datasets contain linked records. Missing datasets are listed below.
DATASETROWSWINDOWSTATUS
Accident, Injuries, and Illnessessafety · contractors346Jan 10, 2000—Aug 25, 2026mine-keyed
Addresses of Recordidentity · logistics1Oct 8, 1975—Oct 8, 1975mine-keyed
Assessed Violationscompliance · legal2,003Feb 22, 2000—Jul 23, 2026mine-keyed
Civil Penalty Dockets and Decisionscompliance · legal211May 27, 2005—Aug 21, 2026mine-keyed
Coal Dust Sampleshealth · safety—No published rowsabsent / not applicable
Conferencescompliance · legal91Mar 30, 2000—Sep 23, 2026mine-keyed
Contested Violationscompliance · legal211Jul 14, 2004—Aug 21, 2025mine-keyed
Contractor Employment and Production — Quarterlycontractors · production · safety6,896Not published—Not publishedentity-linked
Contractor Employment and Production — Yearlycontractors · production · safety1,349Not published—Not publishedentity-linked
Controller and Operator Historyidentity · compliance1Jan 1, 1950—Jan 1, 1950mine-keyed
Mine Employment and Production — Quarterlyproduction · safety · compliance318Not published—Not publishedmine-keyed
Mine Employment and Production — Yearlyproduction · safety · compliance81Not published—Not publishedmine-keyed
Inspectionssafety · compliance235Feb 22, 2000—Oct 5, 2026mine-keyed
Minesidentity · production · logistics1Not published—Not publishedmine-keyed
Metal and Nonmetal Area Sampleshealth · safety14Nov 7, 2014—Jul 17, 2020mine-keyed
Metal and Nonmetal Personal Health Sampleshealth · safety50Dec 27, 2000—Sep 10, 2026mine-keyed
Noise Sampleshealth · safety · equipment—No published rowsabsent / not applicable
Quartz Samples — Coalhealth · safety—No published rowsabsent / not applicable
Violationscompliance · safety · legal2,029Feb 22, 2000—Oct 7, 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.