Thornton Plant
Active
Surface
Nonmetal
Operator: Black Hills Bentonite A Limited Liability Co
Controller: BHB Limited Partnership; A&M Products
Location: Upton, Weston County, WY
Employees: 6
115
Violations
24
S&S Violations
19
Accidents
$34K
Penalties
Recent Violations
View all 115 →| Date | Section | S&S | Negligence | Penalty |
|---|---|---|---|---|
| 10/22/2025 | 56.14130(i) | Non-S&S | ModNegligence | $151 |
| 10/22/2025 | 56.12028 | Non-S&S | ModNegligence | $151 |
| 04/03/2025 | 56.12030 | Non-S&S | ModNegligence | $193 |
| 04/03/2025 | 56.4230(a)(1) | Non-S&S | HighNegligence | $642 |
| 10/08/2024 | 56.18002(b) | Non-S&S | ModNegligence | $147 |
| 10/08/2024 | 56.14100(b) | Non-S&S | ModNegligence | $147 |
| 10/08/2024 | 56.4102 | Non-S&S | ModNegligence | $147 |
| 10/08/2024 | 56.14100(a) | Non-S&S | ModNegligence | $147 |
| 06/05/2024 | 56.11001 | Non-S&S | ModNegligence | $147 |
| 06/05/2024 | 47.42(a) | S&S | ModNegligence | $535 |
| 06/05/2024 | 56.4430(a)(3) | Non-S&S | ModNegligence | $147 |
| 01/31/2024 | 56.14107(a) | Non-S&S | ModNegligence | $147 |
| 01/31/2024 | 56.14107(a) | Non-S&S | ModNegligence | $147 |
| 01/31/2024 | 56.14200 | S&S | HighNegligence | $736 |
| 01/31/2024 | 47.41(a)(1) | Non-S&S | ModNegligence | $147 |
| 01/31/2024 | 47.44(b) | Non-S&S | ModNegligence | $147 |
| 03/15/2023 | 56.14115(b) | Non-S&S | ModNegligence | $143 |
| 03/15/2023 | 56.14100(b) | Non-S&S | ModNegligence | $143 |
| 03/15/2023 | 56.12028 | Non-S&S | LowNegligence | $143 |
| 04/06/2022 | 56.15004 | S&S | ModNegligence | $273 |
Accidents & Injuries
View all 19 →| Date | Classification | Injury | Days Lost |
|---|---|---|---|
| 08/20/2024 | HANDTOOLS (NONPOWERED) | DAYS AWAY FROM WORK ONLY | 211d lost |
| 05/14/2024 | SLIP OR FALL OF PERSON | DAYS AWAY FROM WORK ONLY | 2d lost |
| 01/31/2024 | HANDLING OF MATERIALS | DAYS AWAY FROM WORK ONLY | 116d lost |
| 01/11/2024 | SLIP OR FALL OF PERSON | DAYS AWAY FROM WORK ONLY | 364d lost |
| 12/16/2023 | HANDTOOLS (NONPOWERED) | NO DYS AWY FRM WRK,NO RSTR ACT | None |
| 05/05/2023 | SLIP OR FALL OF PERSON | DAYS AWAY FROM WORK ONLY | 76d lost |
| 06/01/2022 | OTHER | INJURIES DUE TO NATURAL CAUSES | None |
| 04/16/2021 | HANDLING OF MATERIALS | DAYS AWAY FROM WORK ONLY | 11d lost |
| 04/14/2020 | HANDLING OF MATERIALS | DAYS AWAY FROM WORK ONLY | 1d lost |
| 11/01/2017 | HANDTOOLS (NONPOWERED) | DAYS AWAY FROM WORK ONLY | 20d lost |
Inspections
View all 69 →| Begin | End | Hours | Inspectors |
|---|---|---|---|
| 10/22/2025 | 11/03/2025 | 13.00 | 1 |
| 04/03/2025 | 04/04/2025 | 16.00 | 1 |
| 10/08/2024 | 10/09/2024 | 20.00 | 1 |
| 06/05/2024 | 06/17/2024 | 18.50 | 1 |
| 05/22/2024 | 05/22/2024 | 1.50 | 1 |
| 01/31/2024 | 02/13/2024 | 20.50 | 1 |
| 08/22/2023 | 08/28/2023 | 11.50 | 1 |
| 03/14/2023 | 03/16/2023 | 22.00 | 1 |
| 06/02/2022 | 06/16/2022 | 3.50 | 1 |
| 04/05/2022 | 04/20/2022 | 24.00 | 1 |
Mine Details
MSHA Mine ID4801042
Mine TypeSurface
StatusActive
CommodityNonmetal
SIC DescriptionBentonite
Employees6
Days/Week7.0
Hours/Shift12.0
Coordinates44.1497220, -104.7505560
Nearest TownUpton
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Frequently Asked Questions
How many MSHA violations does Thornton Plant have?
Thornton Plant has 115 MSHA violations on record, of which 24 are classified as Significant & Substantial (S&S). Total proposed penalties amount to $34K.
What type of mine is Thornton Plant?
Thornton Plant is a Surface mine producing Nonmetal, located in Upton, Weston County, WY. It currently has 6 employees.
Has anyone been injured or killed at Thornton Plant?
According to MSHA records, Thornton Plant has 19 reported accident/injury records and 0 fatalities on file.
Who operates Thornton Plant?
Thornton Plant is operated by Black Hills Bentonite A Limited Liability Co and controlled by BHB Limited Partnership; A&M Products. MSHA Mine ID: 4801042.