United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued April 26, 2023 Decided June 16, 2023

No. 22-1242

PEABODY MIDWEST MINING, LLC AND MICHAEL BUTLER,

EMPLOYED BY PEABODY MIDWEST MINING, LLC,

PETITIONERS

v.

SECRETARY OF LABOR, MINE SAFETY AND HEALTH 

ADMINISTRATION (MSHA) AND FEDERAL MINE SAFETY AND 

HEALTH REVIEW COMMISSION,

RESPONDENTS

On Petition for Review of a Decision of the

Federal Mine Safety and Health Review Commission

R. Henry Moore argued the cause and filed the briefs for 

petitioners. Patrick W. Dennison entered an appearance.

Susannah M. Maltz, Attorney, U.S. Department of Labor, 

argued the cause for respondents. With her on the brief was 

Emily Toler Scott, Counsel for Appellate Litigation.

Before: PILLARD, KATSAS and RAO, Circuit Judges.

Opinion for the Court filed by Circuit Judge PILLARD. 
2

PILLARD, Circuit Judge: In the early morning hours on 

July 23, 2018, drillers at the Francisco underground coal mine 

hit a pocket of gases, causing methane to blast into their 

worksite in highly volatile concentrations. Methane is 

considered the most dangerous gas in underground mining; in 

sufficient concentrations, methane can ignite and cause a 

potentially catastrophic explosion. To protect worker safety,

Mine Safety and Health Administration (MSHA) regulations

thus require miners to deenergize equipment and cease work 

when they detect certain methane concentrations. But during 

the methane inundation at the Francisco mine the miners did 

not stop work. They instead continued operating an energized 

drill, trying to stop the flow of methane. 

MSHA issued two orders citing the mine operator, 

Peabody Midwest Mining, LLC, for violating the applicable 

safety regulations and designated those violations as 

unwarrantable failures. It also individually cited the mine’s 

manager, Michael Butler, as Peabody’s agent. An 

administrative law judge and then the Federal Mine Safety and 

Health Review Commission agreed with MSHA that Peabody 

violated MSHA safety regulations, that those violations 

constituted unwarrantable failures, that mine manager Butler 

was individually liable, and that civil penalties were 

appropriate. Peabody and Butler petitioned for review in this 

court. We deny the petition. MSHA safety regulations 

unambiguously prohibited Peabody’s operation of an 

energized drill in a high-methane environment, and substantial 

evidence supports the Commission’s unwarrantable failure and 

individual liability determinations.
3

BACKGROUND

A.

Congress enacted the Federal Mine Safety and Health Act 

(Mine Act) to “protect the health and safety of the Nation’s coal 

or other miners.” 30 U.S.C. § 801(g). Under the Act, “[t]he 

Labor Secretary, acting through MSHA, sets regulatory 

standards for mine safety, conducts regular mine inspections 

and issues citations and orders in response to violations.” Sec’y 

of Labor v. Knight Hawk Coal, LLC, 991 F.3d 1297, 1300 

(D.C. Cir. 2021); see generally 30 U.S.C. §§ 811, 813-15, 820. 

The Federal Mine Safety and Health Review Commission 

(FMSHRC or Commission) is an independent adjudicatory 

body that reviews citation, penalty, and order decisions by 

MSHA. Knight Hawk Coal, 991 F.3d at 1300; see 30 U.S.C. 

§§ 815(d), 823. 

Methane is considered mining’s deadliest gas. A 

byproduct of coal, methane is often present in underground 

coal mines. When methane concentrations in the air reach 5% 

by volume, the gas becomes explosive. An ignition source, 

such as a spark from electrical equipment, can light the 

methane and trigger a potentially deadly explosion. 

MSHA safety standards prescribe actions that mine 

operators must take to address methane as it accumulates in 

different parts of a mine. See 30 C.F.R. § 75.323. The 

standards are tiered, requiring additional steps as methane 

concentrations increase. As relevant here, subsection 

75.323(c) lays out what operators must do when methane 

accumulates in a return air split (an airway ventilating air away 

from a working face or worksite and out of the mine). That

subsection provides: 
4

(1) When 1.0 percent or more methane is present 

in a return air split . . . changes or adjustments 

shall be made at once to the ventilation 

system to reduce the concentration of 

methane in the return air to less than 1.0 

percent.

(2) When 1.5 percent or more methane is present 

in a return air split . . .

(i) Everyone except those persons referred 

to in § 104(c) of the Act shall be 

withdrawn from the affected area;

(ii) Other than intrinsically safe AMS, 

equipment in the affected area shall be 

deenergized, electric power shall be 

disconnected at the power source, and 

other mechanized equipment shall be 

shut off; and

(iii) No other work shall be permitted in the 

affected area until the methane 

concentration in the return air is less than 

1.0 percent.

Id. § 75.323(c). AMS is not defined in the rule or record but 

apparently refers to atmospheric monitoring systems. 

Two provisions are principally at issue in this case. The 

first is subparagraph (c)(2)(ii), which we here refer to as the 

deenergization-and-disconnection provision. That provision 

requires operators to deenergize equipment, disconnect electric 

power, and shut off mechanized equipment when methane 

levels reach 1.5%. Id. § 75.323(c)(2)(ii). The second is 

subparagraph (c)(2)(iii), or the no-other-work provision, which 
5

prohibits any “other work” until methane levels return to below 

1%. Id. § 75.323(c)(2)(iii). 

B.

This case arises out of a methane inundation at the 

Francisco underground coal mine in Indiana. Peabody 

Midwest Mining, LLC (Peabody) operates the Francisco mine. 

In July 2018, Peabody contracted with REI Drilling to conduct 

exploratory drilling for abandoned mine works. Mine 

operators often conduct exploratory drilling ahead of coal 

extraction to avoid inadvertently encountering abandoned mine 

works during the mining itself. 

During the early morning hours on July 23, 2018, an REI 

Drilling employee, Robert Ferrin, and a Peabody miner, John 

Stevens, were conducting exploratory drilling at the mine. 

Including miners working elsewhere in the mine, there were 

approximately 60 people underground at the time. At around 

1:49 a.m., the exploratory drill hit a void, meaning it punched 

through solid matter and opened a pocket of gases. Air and 

methane began to blast through the borehole. Moments later, 

a personal methane detector (or “spotter”) worn by Stevens 

began to alarm and read “over range,” indicating methane 

levels in excess of 5% by volume. At some point, Ferrin’s 

methane spotter also began to alarm and read over range.

Stevens phoned to ask the mine manager, Michael Butler, 

to come to the drill site. Butler arrived at the drill site within a 

few minutes. When Butler arrived, Ferrin and Stevens were 

using an energized drill to pull drill rods out of the borehole to 

clear the hole so they could try to plug it and stop the methane 

inundation. Butler leaned in to speak to Ferrin and, as he did 

so, his spotter also alarmed to signal that it detected methane 

levels in excess of 5%. Ferrin told Butler that they needed to 

remove the rods and plug the hole. Butler agreed to that plan. 
6

Butler then directed a maintenance foreman to deenergize 

other equipment, kill power on the unit, and evacuate other 

miners, which the foreman did. But Butler explicitly instructed

the foreman to maintain power to the drill. 

Stevens and Ferrin continued using the drill to pull drill 

rods. The drill had a safety feature to prevent methane 

explosions: Its methane sensor automatically shut down the 

drill when methane levels exceeded 2%. While Ferrin and 

Stevens were working, the drill shut itself down two or three 

times. Each time the drill shut down, the men waited a few 

minutes for the methane levels to drop low enough so that they 

could repower the drill. 

Before long, the mine’s tracking office contacted

Peabody’s General Manager of the Francisco mine, Brad 

Rigsby, at his home. Rigsby ordered that all mining operations 

at the unit cease and that the miners “get ready to pull out.” 

Hr’g Tr. 401 (J.A. 257). While driving to the mine, Rigsby

called the MSHA District Manager to report the methane 

inundation. When he arrived at the mine, Rigsby called Butler, 

who informed Rigsby that the drillers were preparing to plug 

the borehole. Rigsby, who had not known that the drill was 

energized and that miners remained at the worksite, told Butler 

to cut power to all equipment and bring everyone out of the 

unit. As for the methane pouring out of the borehole, Rigsby 

told Butler to “let it bleed.” Peabody Midwest Mining, LLC, 

44 FMSHRC 515, 518 (2022) (quoting Hr’g Tr. 404-05, 415). 

Rigsby’s evacuation order came at least a half hour or so after 

Butler first arrived at the drill site. The miners evacuated 

shortly thereafter. 

As relevant here, MSHA issued two orders to Peabody for 

violating mine safety regulations during the methane 

inundation. The first was for failing to deenergize the unit and 
7

disconnect power once methane concentrations exceeded 

1.5%. See Order No. 9106663 (J.A. 39-40, 70-71); 30 C.F.R. 

§ 75.323(c)(2)(ii). The second was for permitting other 

work—i.e., authorizing miners to pull rods and plug the 

borehole—when methane had not decreased to or below 1.0%. 

See Order No. 9106664 (J.A. 41, 72); 30 C.F.R. 

§ 75.323(c)(2)(iii). Both orders were designated as 

“unwarrantable failures,” a designation MSHA applies to

aggravated conduct beyond ordinary negligence. MSHA also 

determined that Butler was individually liable because he 

knowingly authorized and carried out the violations. MSHA 

proposed civil penalties against both Peabody and Butler. 

The Secretary of Labor then petitioned an administrative 

law judge (ALJ) for penalty assessments. The ALJ held an 

evidentiary hearing and issued a consolidated decision and 

order finding both violations to be unwarrantable failures and 

imposing penalties on Peabody and on Butler individually as 

Peabody’s agent. Peabody and Butler contested the orders 

before the Federal Mine Safety and Health Review 

Commission, which affirmed. Peabody and Butler then timely 

petitioned for review in this court. 

DISCUSSION

We review the Commission’s legal conclusions de novo

and findings of fact for substantial evidence. Knight Hawk 

Coal, 991 F.3d at 1306. When interpreting a MSHA safety 

standard, if “there is only one reasonable construction of [the] 

regulation,” then “the court must give it effect, as the court 

would any law.” Kisor v. Wilkie, 139 S. Ct. 2400, 2415 (2019). 

Peabody and Butler advance three principal arguments in 

their petition. First, they contend that Peabody did not violate 

MSHA safety standards by allowing a drill team to continue 

working in a high-methane environment to remove rods and 
8

attempt to plug the borehole. Second, they challenge the 

unwarrantable failure determinations. Third, they contest 

Butler’s individual liability for any violation, arguing that he 

acted reasonably and in good faith to abate the methane hazard. 

We hold that Peabody violated the applicable MSHA safety 

standards. We further sustain the Commission’s 

determinations that substantial evidence showed Peabody’s 

violations to be unwarrantable failures and supported Butler’s

individual liability. 

A.

Peabody first argues that it did not violate the MSHA 

safety regulation prohibiting “other work” when methane 

levels exceed 1.5% because the work it conducted—pulling 

drill rods and attempting to plug the borehole—was intended 

to stop the methane inundation. We hold that the no-otherwork provision unambiguously prohibited Peabody’s work 

using an energized drill in those circumstances. 

Recall that MSHA safety regulations impose three 

requirements when methane levels exceed 1.5% in a return air 

split: Mine operators must (i) withdraw everyone from the 

affected area (except for certain exempt individuals), 

(ii) deenergize equipment (other than specific intrinsically safe 

equipment) and disconnect the power source, and (iii) permit 

“[n]o other work” until methane levels fall below 1.0%. 30 

C.F.R. § 75.323(c)(2). Recall also that Peabody challenges two 

MSHA orders. The first was for failing to deenergize the drill 

when methane exceeded 1.5%, in violation of the 

deenergization-and-disconnection provision, subparagraph

(c)(2)(ii). The second was for permitting “other work”—that 

is, pulling rods and attempting to plug the borehole—when 

methane levels had not fallen below 1.0%, in violation of the 

no-other-work provision, subparagraph (c)(2)(iii). 
9

Peabody challenges the finding of a violation only as to the 

second order involving the no-other-work provision, having 

conceded before the Commission that it violated the 

deenergization-and-disconnection provision. The facts 

underpinning that second order are largely undisputed: In an 

area with methane levels fluctuating above 1.5%, Peabody 

attempted to abate the methane by pulling drill rods with an 

energized drill. The question before us is thus a legal one: 

whether the no-other-work provision barred Peabody’s work 

with an energized drill. 

The Secretary urges that the bar against “other work” 

prohibits all but work necessary to withdraw miners, 

deenergize equipment, and disconnect power at the source. 

Peabody counters that the provision should be read to allow 

ventilation control and other work aimed at reducing methane, 

like plugging the borehole. To bolster its argument, it points in 

part to another provision of MSHA safety regulations requiring 

“changes or adjustments [to] be made at once to the ventilation 

system” in a return “when 1.0 percent or more methane is 

present.” 30 C.F.R. § 75.323(c)(1) (emphasis added). 

According to Peabody’s logic, the standard in paragraph (c)(1) 

permits ventilation adjustments, as it broadly construes the 

term, whenever methane is above 1%, even when it exceeds 

1.5%. 

We, like the Commission, conclude that “it is unnecessary 

to fully define the categories of work” prohibited by the noother-work provision. Peabody Midwest Mining, 44 FMSHRC 

at 522. Even assuming some ventilation adjustments might be 

permitted when methane exceeds 1.5%, the MSHA regulations 

plainly prohibit Peabody’s use of an energized drill to try to 

plug the borehole and thereby lower methane levels. After all, 

paragraph (c)(2), requiring the operator to conduct “[n]o other 

work,” also requires the operator to withdraw miners and to 
10

deenergize and disconnect power. 30 C.F.R. § 75.323(c)(2)(i)-

(iii). Given the separate requirement for operators to 

“deenergize[]” equipment and “disconnect[]” electric power

when methane levels exceed 1.5%, the no-other-work 

provision must at minimum bar work with an electrically

powered drill. Id. § 75.323(c)(2)(ii). In other words, our 

interpretation of the no-other-work provision “cannot conflict 

with the plainly stated requirement in subparagraph (c)(2)(ii) 

that all equipment be de-energized.” Peabody Midwest 

Mining, 44 FMSHRC at 522. 

Interpreting the no-other-work provision to at least 

prohibit energized work is consistent with the standards’ 

purposes. MSHA safety regulations aim to protect miners from 

methane, “the most dangerous gas encountered by miners 

working underground.” Safety Standards for Underground 

Coal Mine Ventilation, 61 Fed. Reg. 9764, 9777 (1996). They

“establish[] action levels” below the 5% explosive limit “to 

permit appropriate actions to be taken by mine operators in 

order to prevent an explosion.” Id. “Deenergizing or shutting 

off” electrical equipment “protects miners by preventing th[at] 

equipment from providing ignition sources.” Id. at 9778. 

Permitting energized work when methane levels exceed 1.5% 

would ill serve those purposes. Indeed, energized work in a 

high-methane environment creates the very risk of explosion 

that the MSHA safety regulations seek to avert. 

Peabody protests that our interpretation of the no-otherwork provision renders the two orders “duplicative,” such that 

it has been punished twice for the same act: not deenergizing 

the drill. But MSHA orders and citations are not duplicative 

“as long as the standards allegedly violated impose separate 

and distinct duties.” Ky. Fuel Corp., 38 FMSHRC 1614, 1616 

(2016). Here, the deenergization-and-disconnection provision 

and the no-other-work provision imposed separate duties: 
11

Peabody had a duty to deenergize the drill, and it had a duty 

not to use the drill to conduct any work. Even if Peabody had 

for some reason left the drill energized, it could have still

avoided the second MSHA order by choosing not to continue 

working with the drill within the mine. Similarly, Peabody 

could have avoided the first violation by doing some form of 

disallowed work that did not involve energized equipment. 

Peabody’s violation of the no-other-work provision thus 

encompasses “conduct . . . that was not already considered” in 

its violation of the deenergization-and-disconnection 

provision. Id. at 1617. 

Finally, Peabody attempts to invoke a “diminution-ofsafety” or “greater-hazard” defense, arguing that 

noncompliance with the regulations was safer than compliance. 

A diminution-of-safety defense is generally available only 

when a mine operator first petitions MSHA for a modification 

of the standard, see 30 U.S.C. § 811(c), which Peabody agrees 

it neither did nor had the time to do on the morning of July 23. 

To raise such a defense without a petition for modification, 

Peabody would have had to show that (1) the hazards of 

compliance are greater than those of noncompliance, 

(2) alternative means of protecting miners were unavailable, 

and (3) a modification proceeding would have been 

inappropriate. Westmoreland Coal Co., 7 FMSHRC 1338, 

1341 (1985). 

Peabody forfeited any such defense. Under the Mine Act, 

“[n]o objection that has not been urged before the Commission 

shall be considered by th[is] court, unless the failure or neglect 

to urge such objection shall be excused because of 

extraordinary circumstances.” 30 U.S.C. § 816(a)(1). Peabody 

only glancingly alluded to the logic behind a diminution-ofsafety or greater-hazard defense in its post-hearing brief before 

the ALJ and in a footnote in its brief before the Commission. 
12

“[A]t no point” did Peabody explain how it met the three 

requirements for asserting such a defense without a petition for 

modification. Marshall Cnty. Coal Co. v. FMSHRC, 923 F.3d 

192, 205 (D.C. Cir. 2019). Because Peabody’s attempted 

defense is too little too late, we do not consider it. 

B.

Next, Peabody argues that neither order should have been 

designated an “unwarrantable failure.” Under the Mine Act, 

the Secretary may find certain violations “to be caused by an 

unwarrantable failure” to comply with MSHA health or safety 

standards. 30 U.S.C. § 814(d)(1). An “unwarrantable failure” 

involves “aggravated conduct, constituting more than ordinary 

negligence, by a mine operator in relation to a violation of the 

Act.” Black Beauty Coal Co. v. FMSHRC, 703 F.3d 553, 560 

(D.C. Cir. 2012) (quoting Jim Walter Res., Inc. v. Sec’y of 

Labor, 103 F.3d 1020, 1025 (D.C. Cir. 1997)). 

The Commission uses a multifactor test to determine 

whether a violation stems from an unwarrantable failure. It 

considers whether the violation posed a high degree of danger; 

the extent of the violative condition; whether the violation was 

obvious; the operator’s knowledge of the violation; the length 

of time that the violation existed; the operator’s efforts in 

abating the violative condition; and whether the operator was 

on notice that greater efforts were necessary for compliance. 

Id. at 560. “While an administrative law judge may determine, 

in his discretion, that some factors are not relevant, or may 

determine that some factors are much less important than other 

factors under the circumstances, all of the factors must be taken 

into consideration and at least noted by the judge.” Id. (quoting 

IO Coal Co., 31 FMSHRC 1346, 1351 (2009)). The ALJ here 

acknowledged Peabody’s good faith efforts to stanch the flow 

of methane. But the ALJ found that those actions were not 
13

reasonable where the violative conditions were highly 

dangerous, extensive, obvious, known, and of sufficient 

duration to constitute an unwarrantable failure. 

We sustain the unwarrantable failure determinations. The 

ALJ considered each factor, reasonably deeming one factor—

prior, similar violations providing notice of a need for greater 

compliance efforts—to be irrelevant in the absence of any 

evidence of past violations. Substantial evidence supports the 

factual findings underpinning the unwarrantable failure 

designations. Peabody’s conduct posed a high degree of 

danger because “methane levels nearby [the energized drill] 

exceeded five percent, creating the conditions that could have 

led to combustion and a major accident.” Peabody Midwest 

Mining, 44 FMSHRC at 523-24 (quoting 44 FMSHRC 377,

387 (2021)). The violation was extensive, exposing no less 

than six miners to the risk of an explosion. The violation was

also obvious, as high methane levels set off at least three 

methane spotters and caused the drill to shut off at least twice. 

Furthermore, Peabody knew of the violative condition: Butler, 

as Peabody’s agent, knew of multiple methane detectors

signaling high levels of methane, yet he approved continued 

use of the drill, even directing that power to the drill be 

maintained as other power was shut off. As for the duration of 

the violative condition, the Commission rightly recognized that 

“substantial evidence only supports a finding that energized 

work was ongoing for approximately half an hour.” Peabody 

Midwest Mining, 44 FMSHRC at 525. The 30-minute violation 

may have been brief, but “the brief duration of a violative 

condition . . . does not militate against a finding of 

unwarrantable failure if the hazardous condition is ‘readily 

distinguishable from other types of violations’ due to the ‘high 

degree of danger’ it poses and its ‘obvious nature.’” Knight 

Hawk Coal, LLC, 38 FMSHRC 2361, 2371 (2016) (quoting 

Midwest Material Co., 19 FMSHRC 30, 36 (1997)). The 
14

obvious and highly risky methane exposures here meet that 

standard. 

The ALJ credited Peabody’s attempt to abate the influx of 

methane as a mitigating factor in his unwarrantable failure 

analysis. But, as the Commission correctly noted, the relevant 

“[a]batement would consist of stopping work and deenergizing.” Peabody Midwest Mining, 44 FMSHRC at 525 

n.19. So the ALJ should have been asking whether Peabody 

sought to “abat[e] the violative condition,” Black Beauty Coal 

Co., 703 F.3d at 560 (quoting IO Coal Co., 31 FMSHRC at 

1351)—that is, to abate the failure to stop work and to 

deenergize equipment. Peabody instead continued work with 

energized equipment. While Peabody sought to abate one 

perceived hazard (the methane inundation), those efforts 

created the violative condition (work with an energized drill in 

the presence of six miners while methane concentrations

exceeded 1.5%) and the attendant risk of explosion. 

Lastly, Peabody challenges the unwarrantable failure 

determinations on the ground that it reasonably believed that it

was complying with the relevant safety standards. An 

operator’s reasonable, good-faith belief that its cited conduct 

was the safest method of compliance with the regulations can 

be a defense to an unwarrantable failure determination. Cyprus 

Plateau Mining Corp., 16 FMSHRC 1610, 1614-16 (1994). 

But, while Peabody may have sincerely believed it was acting 

safely, “no prudent operator would have believed that it was 

reasonable” regulatory compliance to disregard the clear 

prescriptions of the MSHA regulations and keep the drill 

energized in a high-methane environment. Peabody Midwest 

Mining, 44 FMSHRC at 526 n.20 (quoting 44 FMSHRC at 

388). That is especially true given the well-known dangers in 

combining elevated methane levels with a possible ignition 

source. 
15

C.

We now turn to the decision to hold Butler, as a corporate 

agent for Peabody, individually liable for the violations. Under 

the Mine Act, corporate agents are liable for a safety violation 

if they “knowingly authorized, ordered, or carried out [the] 

violation.” 30 U.S.C. § 820(c). To be individually liable, an 

agent must demonstrate “aggravated conduct,” not just 

“ordinary negligence.” Freeman United Coal Mining Co. v. 

FMSHRC, 108 F.3d 358, 363 (D.C. Cir. 1997) (quoting 

BethEnergy Mines, Inc., 14 FMSHRC 1232, 1245 (1992)). 

Under longstanding Commission precedent, an agent of an 

operator may be liable where he is “in a position to protect 

employee safety and health [and] fails to act on the basis of 

information that gives him knowledge or reason to know of the 

existence of a violative condition.” Kenny Richardson, 3 

FMSHRC 8, 16 (1981). 

Substantial evidence supports the Commission’s decision 

to subject Butler to individual liability. Butler knew of the 

violative condition: He knew that several spotters, including 

his own, were reading “over range,” indicating methane levels 

in excess of 5%, yet he personally asked that the drill remain 

energized. Butler was also in a position to remedy the violation

and protect employee safety. He acknowledged that he was the 

“number one man” on site and could order the miners to cut 

power and stop pulling rods “if [he] felt that was needed.” Hr’g 

Tr. 365-66 (J.A. 250-51). Instead of immediately and directly 

abating the methane risk in the manner the regulation directs, 

Butler authorized continued operation of the energized drill. 

In contesting his liability, Butler argues that he acted in 

good faith to address the hazard presented by the unplugged 

borehole. Under Commission precedent, a good-faith belief in 

the safety of the cited conduct can be a defense to individual 
16

liability under 30 U.S.C. § 820(c) only if it is also reasonable 

in the circumstances. See Lafarge Constr. Materials, 20 

FMSHRC 1140, 1150 (1998). The Commission did not err in 

rejecting Butler’s attempted defense. While Butler acted in 

good faith to address the perceived methane hazard, taking 

what he believed to be the best course in an emergency 

situation, his belief in the safety of plugging the borehole was 

unreasonable. Multiple methane sensors alarmed and the drill 

shut itself down because methane had reached levels MSHA’s 

regulations treat as posing extreme risk. Yet, Butler authorized 

the miners to keep working despite the danger. As the 

Commission recognized, “[b]y permitting miners to work with 

energized equipment, Butler risked incurring the very hazard 

section 75.323(c)(2) is intended to address, i.e., potential 

ignition [in a] high-methane environment.” Peabody Midwest 

Mining, 44 FMSHRC at 528. 

* * *

For the foregoing reasons, we deny Peabody and Butler’s 

petition for review. 

So ordered.