Portable Pioneer Plant has $85K in proposed MSHA penalties and $22K outstanding across 3 contested dockets, plus health sampling and the full incident record.
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Fatalities
0
Total incidents
4
Years on record
1991–2021
Latest incident
Oct 2021
Compliance record
MSHA citations since 2000
222
citations
80
significant & substantial
$84,728
proposed penalties
$57,824
paid to date
68% of proposed penalties paid to date, a $26,904 gap.
citations per 100 inspection hours
ⓘThis rate is recorded citations divided by MSHA inspection hours, per 100 hours. It reflects inspection effort, not mine size or production.
Rate withheld: 876 inspection hours is too few for a stable rate. A minimum of 1,000 inspection hours is required.
Source: MSHA inspections data, updated weekly.
Portable Pioneer Plant has $85K in proposed MSHA penalties and $22K outstanding across 3 contested dockets.
Penalty disposition
ⓘDifferences between proposed and paid penalties reflect both settlements and conference reductions and amounts still owed. Outstanding is the balance currently owed.
$85K
proposed penalties
$80K
current assessed
$58K
paid to date
$22K
outstanding
217 assessments are final orders; 3 contested dockets.
Of $23K in penalties contested before the Commission, $15K was upheld in final decisions.
As of the most recent assessment on 2026-05-27.
Source: MSHA assessed-violations and conference/litigation data, updated weekly.
Violation severity profile
ⓘShares are computed over citations that carry the MSHA gravity and negligence coding; a small share of records are uncoded.
Source: MSHA violations gravity and negligence coding, updated weekly.
When citations were contested
ⓘContesting a citation before the Federal Mine Safety and Health Review Commission is a lawful right. These figures state the public outcomes of that process, from MSHA's Contested Violations file.
34citations taken to the federal commission · 15% of citations on record
Settled
27 · 79%
Vacated or withdrawn
4 · 12%
Still open
3 · 9%
90%
S&S designation survived the contest
ⓘCounts a Significant & Substantial citation as surviving when a settlement or judge's decision kept the designation, or the contest was dismissed or defaulted so the citation stands as issued. Vacated and withdrawn citations, and settlements that removed the designation, count against.
of 10 decided S&S contests · industry: 79%
34%
Penalty reduction in decided contests
$23K proposed, $15K after decisions · industry: 39%
Source: MSHA Contested Violations file (public record), updated weekly. A dismissed or defaulted contest leaves the citation standing as issued; a vacated or withdrawn citation is removed from the violation record. Latest contest filed 2026-07-29.
Contested penalties
ⓘA reduction or dismissal at the Commission is a lawful outcome of contesting a proposed penalty. Figures are the proposed amount and the amount upheld in the docket's decision.
Largest penalties this mine contested before the Federal Mine Safety and Health Review Commission, with the outcome on record.
Health sampling
ⓘA sample is a point in time compliance measurement, not an individual exposure history. These figures describe MSHA sampling records and do not establish causation or personal dose.
Metal and nonmetal contaminants (personal samples)
ⓘMany samples are screening measurements of substances with no applicable exposure limit; they are counted as samples but excluded from every over-limit figure. Over-limit shares use only limit-tested samples.
Last sampled: 2026-05-21
0%
of limit-tested samples over the exposure limit
19
samples
6
limit-tested
Most sampled contaminants
Respirable dust, <.1mg8
Quartz, respirable, >1% Qtz7
Unlisted Particulate, respirable, <1% Qtz3
Nuisance dust, respirable, <1% Qtz1
Show the individual readings (19)
Date
Contaminant
Concentration
Limit
Conc / limit
Occupation
2026-05-21
Quartz, respirable, >1% Qtz
0.2
0.69
0.29
Front-end Loader Operator
2026-05-21
Respirable dust, <.1mg
0
Rotary Bucket Ex. Operator
2026-05-21
Respirable dust, <.1mg
0
Truck Driver
2025-11-13
Respirable dust, <.1mg
0
Front-end Loader Operator
2025-11-13
Nuisance dust, respirable, <1% Qtz
0.24
10
0.02
Front-end Loader Operator
2021-10-07
Respirable dust, <.1mg
0
Front-end Loader Operator
2021-10-07
Quartz, respirable, >1% Qtz
0.14
Crusher Oper/Worker
2018-07-10
Quartz, respirable, >1% Qtz
0.27
Front-end Loader Operator
2018-07-10
Unlisted Particulate, respirable, <1% Qtz
0.24
Crusher Oper/Worker
2013-10-29
Respirable dust, <.1mg
0
Crusher Oper/Worker
2013-10-29
Respirable dust, <.1mg
0
Front-end Loader Operator
2010-05-11
Respirable dust, <.1mg
0
Crusher Oper/Worker
2010-05-11
Unlisted Particulate, respirable, <1% Qtz
0.13
Front-end Loader Operator
2010-05-11
Quartz, respirable, >1% Qtz
0.23
1.4
0.16
Laborer, Bullgang
2004-05-19
Unlisted Particulate, respirable, <1% Qtz
0.15
Crusher Oper/Worker
2004-05-19
Respirable dust, <.1mg
0
Front-end Loader Operator
2004-05-19
Quartz, respirable, >1% Qtz
0.31
2.3
0.13
Laborer, Bullgang
2002-07-24
Quartz, respirable, >1% Qtz
0.27
2.37
0.11
Front-end Loader Operator
2002-07-24
Quartz, respirable, >1% Qtz
0.25
0.43
0.58
Crusher Oper/Worker
Source: MSHA respirable dust, quartz, and noise sampling records, updated weekly. Metal/nonmetal contaminant figures come from MSHA's Personal Health Samples and Area Samples files (public record), updated weekly.
Source: MSHA controller and operator history, updated weekly.
Workforce and production
Year
Employees
2026
6
2025
6
2024
5
2023
5
2022
4
2021
4
2020
2
2019
3
2018
4
2017
3
2016
3
2015
3
2014
3
2013
4
2012
4
2011
4
2010
5
2009
4
2008
4
2007
4
2006
4
2005
5
2004
3
2003
3
2002
4
2001
3
2000
2
Source: MSHA quarterly employment and production, updated weekly.
Portable Pioneer Plant sits in Knox County, Maine, where the Census mining category is 0.3% of county employment.
Local economic context
ⓘCounty figures come from the US Census Bureau's American Community Survey, 5-year pooled estimates, so the 2023 vintage covers 2019 through 2023. The Census category is 'mining, quarrying, and oil and gas extraction', which is broader than MSHA jurisdiction and includes oil and gas workers no mine employs. These figures describe the surrounding county, not this mine, and are not a factor in any specific incident.
Knox County, Maine · Population 40,860
0.3%
Mining share of county employment
$71,903
Median household income
Source: US Census Bureau, American Community Survey 2023 5-year estimates.
Quarterly safety rates
ⓘCitations per million reported employee-hours. Rates begin in 2000, when MSHA's quarterly employment data starts; earlier incidents are counted but cannot be rate-adjusted. Quarters under 100,000 reported hours are greyed: too few hours for a stable rate.
Citations per million employee-hours, as reported to MSHA
Quarter
Hours worked
Citations
S&S
Per 1M hrs
2026 Q2
3,351
10
4
2984.2
2026 Q1
1,933
0
0
0.0
2025 Q4
3,238
8
3
2470.7
2025 Q3
3,519
3
0
852.5
2025 Q2
2,067
0
0
0.0
2025 Q1
0
0
0
2024 Q3
798
2
1
2506.3
2024 Q2
1,718
0
0
0.0
Show 97 earlier quartersHide earlier quarters
Quarter
Hours worked
Citations
S&S
Per 1M hrs
2024 Q1
1,092
0
0
0.0
2023 Q4
2,437
8
3
3282.7
2023 Q3
2,946
0
0
0.0
2023 Q2
1,939
0
0
0.0
2023 Q1
492
1
0
2032.5
2022 Q4
1,606
5
0
3113.3
2022 Q3
2,200
0
0
0.0
2022 Q2
2,350
0
0
0.0
2022 Q1
250
0
0
0.0
2021 Q4
1,684
6
1
3562.9
2021 Q3
3,015
0
0
0.0
2021 Q2
1,784
7
1
3923.8
2021 Q1
100
0
0
0.0
2020 Q4
393
0
0
0.0
2020 Q3
1,514
0
0
0.0
2020 Q2
2,146
0
0
0.0
2020 Q1
0
0
0
2019 Q4
1,615
4
2
2476.8
2019 Q3
2,510
0
0
0.0
2019 Q2
2,370
0
0
0.0
2019 Q1
850
0
0
0.0
2018 Q4
2,288
2
0
874.1
2018 Q3
2,450
4
2
1632.7
2018 Q2
2,315
0
0
0.0
2018 Q1
288
0
0
0.0
2017 Q4
1,200
0
0
0.0
2017 Q3
1,961
0
0
0.0
2017 Q2
2,600
0
0
0.0
2017 Q1
2
0
0
0.0
2016 Q4
605
0
0
0.0
2016 Q3
1,810
0
0
0.0
2016 Q2
1,876
0
0
0.0
2016 Q1
0
0
0
2015 Q4
1,261
1
1
793.0
2015 Q3
1,800
0
0
0.0
2015 Q2
1,330
0
0
0.0
2015 Q1
0
0
0
2014 Q4
975
12
1
12307.7
2014 Q3
1,455
0
0
0.0
2014 Q2
1,911
0
0
0.0
2014 Q1
1
0
0
0.0
2013 Q4
973
2
0
2055.5
2013 Q3
1,101
2
0
1816.5
2013 Q2
676
3
0
4437.9
2013 Q1
158
0
0
0.0
2012 Q4
2,366
0
0
0.0
2012 Q3
2,711
0
0
0.0
2012 Q2
2,451
3
0
1224.0
2012 Q1
0
0
0
2011 Q4
1,896
27
8
14240.5
2011 Q3
2,276
8
8
3514.9
2011 Q2
2,451
0
0
0.0
2011 Q1
275
0
0
0.0
2010 Q4
1,601
14
4
8744.5
2010 Q3
2,511
0
0
0.0
2010 Q2
2,511
9
5
3584.2
2010 Q1
406
0
0
0.0
2009 Q4
2,351
0
0
0.0
2009 Q3
2,511
0
0
0.0
2009 Q2
2,231
0
0
0.0
2009 Q1
0
0
0
2008 Q4
1,622
4
2
2466.1
2008 Q3
2,185
4
0
1830.7
2008 Q2
3,000
7
2
2333.3
2008 Q1
450
0
0
0.0
2007 Q4
2,098
0
0
0.0
2007 Q3
2,496
0
0
0.0
2007 Q2
2,400
0
0
0.0
2007 Q1
500
0
0
0.0
2006 Q4
2,001
0
0
0.0
2006 Q3
3,000
0
0
0.0
2006 Q2
3,010
14
6
4651.2
2006 Q1
0
0
0
2005 Q4
682
0
0
0.0
2005 Q3
2,401
0
0
0.0
2005 Q2
3,215
5
3
1555.2
2005 Q1
565
0
0
0.0
2004 Q4
652
0
0
0.0
2004 Q3
360
0
0
0.0
2004 Q2
602
5
2
8305.6
2004 Q1
0
0
0
2003 Q4
2,480
0
0
0.0
2003 Q3
2,560
10
4
3906.2
2003 Q2
2,640
0
0
0.0
2003 Q1
0
0
0
2002 Q4
1,000
0
0
0.0
2002 Q3
1,980
6
4
3030.3
2002 Q2
2,400
0
0
0.0
2002 Q1
1,200
4
0
3333.3
2001 Q4
2,400
0
0
0.0
2001 Q3
2,400
8
7
3333.3
2001 Q2
2,400
0
0
0.0
2001 Q1
0
0
0
2000 Q4
800
0
0
0.0
2000 Q3
1,800
0
0
0.0
2000 Q2
2,450
14
6
5714.3
2000 Q1
0
0
0
No fatalities recorded at this mine.
Reportable incidents
4 on file
2021 · 1 incident
October 8, 2021ME · Metal/Non-Metallaborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitmanHANDTOOLS (NONPOWERED)
While pulling out a rock in a jam in conveyor #2; bar slipped and hit me on the head. This caused employee to fall and hit shoulder on side of plant (eye beam). At first, thought to be muscle sprain. Employee stated that pain got worse, was sent for an x ray. Found employee had neck injuries (pre-existing). We question whether this happened or not. No one saw employee fall.
2011 · 1 incident
October 28, 2011ME · Metal/Non-Metalhaul/off road/coal/ore/pit/quarry/rock/rubber tire truck driver, transportation truck driverSLIP OR FALL OF PERSON