MSHA DATABASEMSHA records · 11 contributing sources · snapshot Oct 13, 2026

MINE DETAILS

HARD ROCK QUARRY

ActiveSurfaceConstruction Sand and Gravel
MSHA MINE ID1700705
LOCATIONKnox, ME
PUBLIC RECORD568 linked rows

LOCATION

Mine location

1 of 1 mine with usable MSHA coordinates. Select a marker to open a mine.

Mine coordinates

2025-01-01 – 2026-10-13Applies to production, safety and portfolio metrics. Silica samples have separate filters.

Violations

23

7 significant & substantial (S&S)

  1. 2025 Q14
  2. 2025 Q20
  3. 2025 Q39
  4. 2025 Q46
  5. 2026 Q10
  6. 2026 Q24
  7. 2026 Q30
  8. 2026 Q4 *0

Accident records

0

0 records classified as fatality

  1. 2025 Q10
  2. 2025 Q20
  3. 2025 Q30
  4. 2025 Q40
  5. 2026 Q10
  6. 2026 Q20
  7. 2026 Q30
  8. 2026 Q4 *0

Proposed penalties · USD

6,053.00

22 of 23 violations with amounts

  1. 2025 Q12,330
  2. 2025 Q2—
  3. 2025 Q31,949
  4. 2025 Q4923
  5. 2026 Q1—
  6. 2026 Q2851
  7. 2026 Q3—
  8. 2026 Q4 *—

On-site inspection hours

42.50

8 inspections · 8 with hours

  1. 2025 Q14.75
  2. 2025 Q2—
  3. 2025 Q314.00
  4. 2025 Q413.00
  5. 2026 Q11.75
  6. 2026 Q29.00
  7. 2026 Q3—
  8. 2026 Q4 *—
Quarterly safety data
QuarterViolationsS&SProposed USDAccident recordsFatality recordsInspectionsOn-site hours
2025-Q1412,330.000024.8
2025-Q200—000—
2025-Q3941,949.0000214.0
2025-Q461923.0000113.0
2026-Q100—0011.8
2026-Q241851.000029.0
2026-Q300—000—
2026-Q4 *00—000—

Most cited CFR sections

All violations issued in the selected period. Counts combine subsections.

Safety activity

  1. inspectionF03E598

    Compliance Follow-up Inspection · 1.0 on-site hours

  2. violation5075454

    56.14100(b) · $151.00 proposed

  3. violation5075453

    56.14132(a) · S&S · $398.00 proposed

  4. violation5075452

    56.14100(b) · $151.00 proposed

  5. violation5075451

    50.30(a) · $151.00 proposed

  6. inspectionF03E593

    Regular Safety and Health Inspection · 8.0 on-site hours

  7. inspectionF02C744

    Compliance Follow-up Inspection · 1.8 on-site hours

  8. violation5071862

    56.14132(a) · $151.00 proposed

  9. violation5071861

    47.41(a) · $151.00 proposed

  10. violation5071860

    56.14100(b) · S&S · $151.00 proposed

  11. violation5071859

    56.12025 · $151.00 proposed

  12. violation5071858

    56.14107(a) · $151.00 proposed

  13. inspection6926696

    Regular Safety and Health Inspection · 13.0 on-site hours

  14. violation5073050

    Description not reported · $168.00 proposed

  15. inspectionF021850

    Spot Inspection · 5.5 on-site hours

  16. violation5073044

    46.12(a)(2) · $151.00 proposed

  17. violation5073043

    46.11(a) · S&S · $504.00 proposed

  18. violation5073042

    56.14107(a) · $151.00 proposed

  19. violation5073041

    56.16007 · S&S · $165.00 proposed

  20. violation5073040

    46.5(a) · S&S · $233.00 proposed

  21. violation5073039

    56.11001 · S&S · $443.00 proposed

  22. violation5073038

    Description not reported

  23. inspectionF011E8B

    Regular Safety and Health Inspection · 8.5 on-site hours

  24. violation5072326

    56.4201(a)(2) · $151.00 proposed

  25. violation5072325

    50.30(a) · $151.00 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.

CURRENT HIERARCHYPeter C Overlock → Peter Overlock Inc → HARD ROCK QUARRY
HISTORY RECORDS39 relationships
INTERVAL CHECKPASScontroller/operator overlap
—

Peter C OverlockcontrolsPeter Overlock IncoperatesHARD ROCK QUARRY

msha-controller-operator-history · controller/operator co-tenure derived on mine 1700705
—

Dwight OverlockcontrolsD L Overlock Excavation LLCoperatesHARD ROCK QUARRY

msha-controller-operator-history · controller/operator co-tenure derived on mine 1700705
—

Dwight OverlockcontrolsD L Overlock ExcavationoperatesHARD ROCK QUARRY

msha-controller-operator-history · controller/operator co-tenure derived on mine 1700705
Other 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 / SAFETYneutral

Accidents and injuries

0 historical accident/injury rows; 0 coded fatalities and 0 lost days across the published record.

ACCIDENT + INJURY RECORD0 since 2021
accidentsmine-production-quarterly
02 / COMPLIANCEwatch

Violations and penalties

101 violation rows across the full record; 21 carry an S&S flag and $16,040 appears in current assessed amounts.

ENFORCEMENT ACTIVITY45 since 2021
inspectionsviolationsassessed-violationsorders-107a
03 / HEALTHcontext

Occupational health samples

6 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 EXPOSURE6 samples
personal-health-samples
04 / PRODUCTIONcontext

Quarterly production and employment

3K employee hours and 4 summed average employees across reported subunits in the latest published quarter.

2026-Q20 tons
mine-production-quarterlymine-production-yearly
05 / LEGALneutral

Contests, conferences and decisions

0 contested-violation rows, 0 civil-penalty docket/decision rows, and 0 conference records linked by issuance number.

POST-ISSUANCE LIFECYCLE0 linked rows
conferencescontested-violationscivil-penalty-dockets-decisions
06 / 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-yearlyaccidentsviolations
07 / INSPECTIONScontext

Inspections

51 inspection events and 663 published inspection hours across the historical record.

OVERSIGHT COVERAGE15 since 2021
inspectionsviolations

HEALTH SAMPLING

Silica and quartz

Matching records00 coal · 0 personal · 0 area
Sample status0 not voided0 voided · 0 status not reported
Personal samples with C/E > 1—0 published ratios · not a citation count
2026 · No reported dates in this selection
Date / sampleDataset / analyteOccupation / areaMeasurementSample statusPublished 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.

RECENT PUBLIC RECORDS

Recent violations and samples

Latest records retained for inspection; aggregates above use the full source history.

VIOLATIONS12 latest shown
507545456.14100(b)Citation
507545356.14132(a)S&S
507545256.14100(b)Citation
507545150.30(a)Citation
507186256.14132(a)Citation
507186147.41(a)Citation
507186056.14100(b)S&S
507185956.12025Citation
OTHER HEALTH SAMPLES4 latest shown

Coal dust, noise and other contaminants. Silica records above ↑

Respirable dust, <.1mgBackhoe Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgFront-end Loader Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgFront-end Loader Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified
Respirable dust, <.1mgFront-end Loader Operator
C/E: 00.00Concentration: 0000.00 · limit: 0000.00Source unit unspecified

SOURCE COVERAGE

Reporting dates and coverage

11 datasets contain linked records. Missing datasets are listed below.

DATASETROWSWINDOWSTATUS
Accident, Injuries, and Illnessessafety · contractors—No published rowsabsent / not applicable
Addresses of Recordidentity · logistics1May 31, 2022—May 31, 2022mine-keyed
Assessed Violationscompliance · legal100Jun 5, 2002—Apr 28, 2026mine-keyed
Civil Penalty Dockets and Decisionscompliance · legal—No published rowsabsent / not applicable
Coal Dust Sampleshealth · safety—No published rowsabsent / not applicable
Conferencescompliance · legal—No published rowsabsent / not applicable
Contested Violationscompliance · legal—No published rowsabsent / not applicable
Contractor Employment and Production — Quarterlycontractors · production · safety81Not published—Not publishedentity-linked
Contractor Employment and Production — Yearlycontractors · production · safety23Not published—Not publishedentity-linked
Controller and Operator Historyidentity · compliance3Jun 1, 2001—Aug 21, 2025mine-keyed
Mine Employment and Production — Quarterlyproduction · safety · compliance157Not published—Not publishedmine-keyed
Mine Employment and Production — Yearlyproduction · safety · compliance44Not published—Not publishedmine-keyed
Inspectionssafety · compliance51Jun 28, 2001—May 7, 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 · safety6Nov 24, 2009—Dec 13, 2023mine-keyed
Noise Sampleshealth · safety · equipment—No published rowsabsent / not applicable
Quartz Samples — Coalhealth · safety—No published rowsabsent / not applicable
Violationscompliance · safety · legal101Jun 5, 2002—Apr 28, 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.