RECOMMENDED FOR FULL-TEXT PUBLICATION
                                 Pursuant to Sixth Circuit I.O.P. 32.1(b)
                                         File Name: 15a0124p.06

                     UNITED STATES COURT OF APPEALS
                                     FOR THE SIXTH CIRCUIT
                                       _________________


 BRANDYWINE EXPLOSIVES & SUPPLY; KENTUCKY ┐
 EMPLOYERS MUTUAL INSURANCE,                   │
                                  Petitioners, │
                                               │                     No. 14-3672
                                               │
       v.                                      >
                                               │
                                               │
 DIRECTOR, OFFICE OF WORKERSʼ COMPENSATION │
 PROGRAMS; RICHARD DEAN KENNARD,               │
                                 Respondents. │
                                               ┘
                          On Petition for Review of a Decision and Order
                                   of the Benefits Review Board.
                                         No. 13-0442 BLA.
                                       Argued: March 6, 2015
                                  Decided and Filed: June 15, 2015

        Before: GRIFFIN and STRANCH, Circuit Judges; STEEH, District Judge.*

                                         _________________

                                             COUNSEL

ARGUED: Mark E. Solomons, GREENBERG TRAURIG, LLP. Washington, D.C., for
Petitioners. Rebecca J. Fiebig, UNITED STATES DEPARTMENT OF LABOR, Washington,
D.C., for Federal Respondent. Evan B. Smith, APPALACHIAN CITIZENSʼ LAW CENTER,
Whitesburg, Kentucky, for Respondent Kennard. ON BRIEF: Mark E. Solomons, Laura
Metcoff Klaus, GREENBERG TRAURIG, LLP. Washington, D.C., for Petitioners. Sean G.
Bajkowski, Rita A. Roppolo, UNITED STATES DEPARTMENT OF LABOR, Washington,
D.C., for Federal Respondent. Evan B. Smith, APPALACHIAN CITIZENSʼ LAW CENTER,
Whitesburg, Kentucky, for Respondent Kennard.




        *
        The Honorable George Caram Steeh, Senior United States District Judge for the Eastern District of
Michigan, sitting by designation.




                                                   1
No. 14-3672         Brandywine Explosives & Supply, et al. v. OWCP, et al.        Page 2

                                      _________________

                                              OPINION
                                      _________________

       JANE B. STRANCH, Circuit Judge. Brandywine Explosives & Supply, along with its
workers’ compensation insurer, seeks review of the findings by an Administrative Law Judge
(ALJ) that its former employee Richard Kennard is entitled to benefits under the Black Lung
Benefits Act, as amended, 30 U.S.C. §§ 901, et seq. As described below, the findings were
supported by substantial evidence. We accordingly DENY the petition for review.

                                         I.      FACTS

       In August 2009, Kennard filed for black lung benefits. He underwent a number of
medical tests and examinations. After the claims examiner initially recommended that his claim
be denied, he sought a hearing before the Department of Labor Office of Administrative Law
Judges. The ALJ concluded that Kennard was entitled to a rebuttable presumption that he had
pneumoconiosis and that the disease caused his total disability because he had worked in
conditions that were substantially similar to those in an underground mine. The ALJ further held
that Brandywine successfully rebutted the presumption that Kennard had clinical
pneumoconiosis.         The employer failed, however, to rebut the presumption of legal
pneumoconiosis or the presumption that Kennardʼs disability was caused by his employment in a
coal mine.    Brandywine appealed to the Benefits Review Board, arguing that the 15-year
presumption should not apply to Kennard and, if the presumption did apply, the company had
successfully rebutted it.

       Between 1977 and 2009, Kennard worked for more than 21 years as a blaster on strip
mines, sometimes directly for a coal company and sometimes for contractors.                At the
administrative hearing and in a deposition, Kennard testified about the environmental conditions
of his blasting work:

       Q: So, was there any rock dust or coal dust that you were exposed to?
       A: Yeah, plenty of it. You couldn’t get away from it. Most time, you’d be right
       on the shot. You didn’t have an air conditioner. You just had to work right there
       close to it. All the dust was flying and you was breathing it.
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.               Page 3

       ....
       There’s a lot of dust flying and it wasn’t self-contained. I mean, [the drill cover]
       couldn’t contain all of it. You got some coming out.
       ....
       Q: And whenever you would blast the holes in which were drilled, what would
       happen then?
       A: A whole lot of dust. Dust would be flying because you’re putting off a charge
       in the ground and you got a whole lot of dust comes in the air.
       Q: Was that mainly rock dust or coal dust or ---
       A: Rock dust, coal dust, everything you could get.
       ....
       Whatever was in the ground. If you’re drilling through little coal seams,
       sometimes you’d drill through little seams five or six inches thick and then when
       you shoot that, it’s all like a big cloud of smoke.

Tr. at 17:8–13, 17–19; 18:1–7, 12–15.

       Q: And doing the blasting aspect of that job would you be exposed to coal, rock,
       sand or other types of dust?
       A: Yes. Exposed to you know rock dust, coal dust and everything you know.
       Q: Obviously though when the shot is set off you are well away from that area?
       A: Yeah, but you have dust to contend with there because it takes so long to get
       back you know and get away from it. Do you know what I’m saying?
       Q: Do they not wait before they go back in to check after a shot until it’s settled?
       A: There’s still a lot of just in the air just floating in the air. It would be like two
       hours before you completely settle it on the ground.
       Q: And would you be the one who would typically the first one to go back?
       A: Yes, the blaster always does that and calls the all clear signals.

Kennard Dep., DX 26 at 16:19–17:15. Kennard performed his work immediately before the
main coal production began at a given site.

       Kennard also has a significant history of smoking—at least 60 pack-years. The smoking
gave him cancer in his right lung, and the lung was removed. He also experiences shortness of
breath (dyspnea), coughing, and sleep apnea. His treating physician diagnosed him with Chronic
Obstructive Pulmonary Disorder (COPD). His breathing is extremely limited at approximately
No. 14-3672          Brandywine Explosives & Supply, et al. v. OWCP, et al.          Page 4

25% of the expected level for a man his age, and he has significant trouble moving around,
especially without external oxygen.

               II.      STATUTORY AND REGULATORY BACKGROUND

A.     General Framework

       The Black Lung Benefits Act (BLBA) provides benefits to coal miners who have become
totally disabled due to pneumoconiosis resulting from their exposure to coal-mine dust.
See 20 C.F.R. § 718.204(a). To establish entitlement to benefits, a miner who files a claim must
prove (1) that he has pneumoconiosis, (2) that the pneumoconiosis arose out of coal mine
employment, (3) that he is totally disabled, and (4) that the disability was due to pneumoconiosis.
20 C.F.R. § 725.202(d)(2). The regulations provide for proof of these elements by lay evidence,
medical evidence, and the application of statutorily created presumptions.             20 C.F.R.
§§ 718.202–205.

       Pneumoconiosis is the technical term for lung disease caused by exposure to dust,
commonly called Black Lung Disease. Under the statute, pneumoconiosis is defined broadly as
“a chronic dust disease of the lung and its sequelae, including respiratory and pulmonary
impairments, arising out of coal mine employment.” 30 U.S.C. § 902(b). The implementing
regulations further clarify that there are two forms of pneumoconiosis for the purposes of the
BLBA: clinical and legal pneumoconiosis. Clinical pneumoconiosis refers to a specific set of
enumerated diseases, while legal pneumoconiosis “is a broader and less definite term that refers
to any chronic lung disease that was caused in this instance by exposure to coal[-mine] dust.”
Central Ohio Coal Co. v. Dir., Office of Workers’ Comp. Programs, 

, 486 (6th Cir.
2014) (emphasis in original); see also 20 C.F.R. § 718.201(a).

       The implementing regulations also establish the degree of causation required for a
miner’s respiratory disability to be considered “due to pneumoconiosis:”

       A miner shall be considered totally disabled due to pneumoconiosis if
       pneumoconiosis . . . is a substantially contributing cause of the miner’s totally
       disabling respiratory or pulmonary impairment.              Pneumoconiosis is a
       “substantially contributing cause” of the miner’s disability if it:
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.           Page 5

       (i)    Has a material adverse effect on the miner’s respiratory or pulmonary
       condition; or
       (ii)   Materially worsens a totally disabling respiratory or pulmonary
       impairment which is caused by a disease or exposure unrelated to coal mine
       employment.

20 C.F.R. § 718.204(c)(1).

       This case concerns a rebuttable presumption for certain miners who worked in coal mines
for at least 15 years and have a totally disabling respiratory impairment and are not otherwise
eligible for a presumption of entitlement. These miners receive “a rebuttable presumption that
such miner is totally disabled due to pneumoconiosis.” 30 U.S.C. § 921(c)(4). To qualify for the
presumption, the 15 years must have been spent either in underground coal mines or a surface
mine such that the miner’s conditions of employment “were substantially similar to conditions in
an underground mine.” 

bears the burden of establishing his entitlement to the
presumption, but once he is found eligible, “the burden of production and persuasion lies on the
employer . . . to rebut the presumption of disability due to pneumoconiosis.” Morrison v. Tenn.
Consol. Coal Co., 

, 479 (6th Cir. 2011).

       The presumption was first added to the BLBA in 1972. See Black Lung Benefits Act of
1972, Pub. L. 92-303 § 4(c), 86 Stat. 150, 154 (1972). In 1981, Congress eliminated the
presumption. Black Lung Benefits Amendments of 1981, Pub. L. 97-119 § 202(b)(1), 95 Stat.
1635, 1644 (1981). Congress reinstated the presumption in 2010, making it retroactive to claims
filed after January 1, 2005 that were pending on or after March 23, 2010. See Patient Protection
and Affordable Care Act (“PPACA”), Pub. L. No. 111-148 § 1556, 124 Stat. 119, 260 (2010).

B.     The Revised Regulation

       While Kennard’s case was pending before the Benefits Review Board, the Department of
Labor promulgated a revised regulation on the 15-year presumption.              See Regulations
Implementing the Byrd Amendments to the Black Lung Benefits Act, 78 Fed. Reg. 59,102
(2013). The former regulation restated the statutory language that addressed which surface
miners are eligible for the presumption, but the new regulation states that “[t]he conditions in a
mine other than an underground mine will be considered ‘substantially similar’ to those in an
No. 14-3672       Brandywine Explosives & Supply, et al. v. OWCP, et al.           Page 6

underground mine if the claimant demonstrates that the miner was regularly exposed to coal-
mine dust while working there.” 20 C.F.R. § 718.305(b)(2).

       With regard to rebuttal, the former regulation stated: “The presumption may be rebutted
only by establishing that the miner does not, or did not have pneumoconiosis, or that his or her
respiratory or pulmonary impairment did not arise out of, or in connection with, employment in a
coal mine.” 20 C.F.R. § 718.305(a) (eff. prior to Oct. 25, 2013). The new regulation states:

       In a claim filed by a miner, the party opposing entitlement may rebut the
       presumption by—
       (i) Establishing both that the miner does not, or did not, have:
       (A) Legal pneumoconiosis as defined in § 718.201(a)(2); and
       (B) Clinical pneumoconiosis as defined in § 718.201(a)(1), arising out of coal
       mine employment (see § 718.203); or
       (ii) Establishing that no part of the miner's respiratory or pulmonary total
       disability was caused by pneumoconiosis as defined in § 718.201.

20 C.F.R. § 718.305(d)(1).

       We have already determined that the new regulation applies to all cases that were
pending when it was promulgated—whether before an ALJ, the Benefits Review Board, or our
court. See Central Ohio Coal 

–90. The new regulation is an interpretive
regulation, and “a new interpretive regulation that is substantially consistent with prior
regulations or prior agency practices, and has been accepted by all Courts of Appeals to consider
the issue, can be applied to cases pending at the time the regulation is promulgated.” 

(internal quotation marks omitted). The new regulation is consistent with prior agency practice.

–90; see also Antelope Coal Co./Rio Tinto Energy Am. v. Goodin, 

, 1342
(10th Cir. 2014). In fact, the Department of Labor chose this regulation to formally adopt the
longstanding approach of the Seventh Circuit—expressed in Dir., Office of Workers’ Comp.
Programs v. Midland Coal Co., 

(7th Cir. 1988). There, the court held that an ALJ
should not require a surface miner to present evidence of conditions in an underground mine
before the ALJ can find substantial similarity to underground-mine conditions. Instead, “[t]he
claimant is required only to produce sufficient evidence of the surface mining conditions under
which he worked. It is then the function of the ALJ, based on his expertise and, we would
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.             Page 7

expect, certain appropriate objective factors . . . to compare the surface mining conditions
established by the evidence to conditions known to prevail in underground mines.” 

The Seventh Circuit further recognized that the most significant conditions for this purpose
involved exposure to dust. See Freeman United Coal Mining Co. v. Summers, 

,
479–80 (7th Cir. 2001). The new regulation therefore applies to this and other cases that were
pending when it was promulgated.

                                       III.    ANALYSIS

A.     Unexhausted Issue

       “Generally, this court will not review issues not properly raised before the [Benefits
Review] Board.” Arch on the Green, Inc. v. Groves, 

, 602 (6th Cir. 2014). “In
providing for review of BRB determinations in the courts of appeals, Congress in effect required
that a [petitioner] exhaust all [its] administrative remedies.” Blevins v. Dir., Office of Workers’
Comp. Programs, 

, 143 (6th Cir. 1982) (internal quotation marks omitted). This
allows “a party aggrieved by the decision of an administrative law judge [to] find corrective
action at the BRB and thereby remove the need for judicial review.” 

recognizes the
particular familiarity and expertise of the agency with Black Lung Benefits matters. See McKart
v. United States, 

, 194–95 (1969) (discussing the general advantages of
administrative exhaustion).

       Though Brandywine now argues that the revised regulation on the 15-year presumption is
invalid, it failed to present any arguments about the validity of the new regulation to the Benefits
Review Board. The company argues that we should nonetheless consider its arguments “because
any challenge in those proceedings would have been futile.” Pet. Br. at 13 n.6. We disagree.
First, we note that the Benefits Review Board has statutory authority to review Department of
Labor regulations for consistency with the Black Lung Benefits Act. Gibas v. Saginaw Min. Co.,

, 1117–19 (6th Cir. 1984). Second, Brandywine had notice of the new regulation
and its application to this case. The Director of the Office of Workers’ Compensation Programs
noted and relied on the new regulation in its response brief before the Benefits Review Board,
but Brandywine did not address the validity of the regulation in its reply brief or otherwise
attempt to raise the issue before the board. Finally, unlike the argument that we found to be
No. 14-3672         Brandywine Explosives & Supply, et al. v. OWCP, et al.          Page 8

futile in Kyle v. Dir., Office of Workers’ Comp. Programs, 

(6th Cir. 1987),
rejection of the new rule would not have required the Board to reverse course from a recently
adopted position.

       We proceed to address the issues that Brandywine did present to the Board: whether
substantial evidence supports the ALJ’s findings that Kennard was entitled to the 15-year
presumption under the new rule and whether Brandywine failed to rebut the presumption.

B.     Standard of Review

       This court has jurisdiction over petitions for review of final decisions of the Benefits
Review Board under 33 U.S.C. § 921(c). The Board’s legal conclusions are reviewed de novo.

. On factual issues, the court, like the Board, determines “whether the
ALJ—not the Board—had substantial evidence upon which to base his or her decision.” Jonida
Trucking, Inc. v. Hunt, 

, 742 (6th Cir. 1997); see also 33 U.S.C. § 921(b)(3).
“‘Substantial evidence’ means ‘such relevant evidence as a reasonable mind might accept as
adequate to support a conclusion.’” Kolesar v. Youghiogheny & Ohio Coal Co., 

,
729 (6th Cir. 1985) (quoting Richardson v. Perales, 

, 401 (1971)). “In referring to a
singular ‘reasonable mind,’ the Supreme Court has directed us to uphold decisions that rest
within the realm of rationality.” Piney Mountain Coal Co. v. Mays, 

, 756 (4th Cir.
1999). “Therefore, we may affirm an ALJ's decision even though we would have taken a
different view of the evidence were we the trier of facts.” Big Branch Resources, Inc. v. Ogle,

, 1069 (6th Cir. 2013) (internal quotation marks omitted).

       In summary, “[a] decision by the Board must be affirmed on appeal if the Board has not
committed any legal error or exceeded its statutory scope of review of the ALJ’s factual
determination,” that is, substantial evidence review. Jonida Trucking, 

.

C.     Kennard’s Eligibility for the Presumption

       Brandywine first challenges Kennard’s eligibility for the 15-year presumption. Because
Kennard worked exclusively on non-underground strip mines, he is eligible for the presumption
only if he can prove that his working conditions at the strip mine were “substantially similar to
conditions in an underground mine.” 30 U.S.C. § 921(c)(4). At the time of his hearing, the
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.           Page 9

regulations did not provide further guidance to the ALJ about how to apply the standard.
Following Benefits Review Board precedent, the ALJ considered Kennard’s uncontested lay
testimony on the dust conditions of his blasting work and compared it to the ALJ’s
understanding of dust conditions in underground coal mines. See D&O at 14 n.36 (citing Spese
v. Peabody Coal Co., BRB No. 90-1856, 

at *4 (DOL Ben. Rev. Bd.)). As noted
above, at pages 6–7, the Board adopted this approach following the Seventh Circuit Midland
Coal 

, and since Kennard’s hearing, the Department of Labor
promulgated the revised regulation on this issue, 20 C.F.R. § 718.305(b)(2).

       The ALJ’s decision was supported by substantial evidence. The ALJ particularly noted
Kennard’s testimony that “all the dust was flying around and you was breathing it” and his
descriptions of “big cloud[s] of smoke” from coal dust, comparing them to the dust conditions
experienced by underground miners. D&O at 14–15. The testimony easily supports a finding
that Kennard was regularly exposed to coal-mine dust.

       Brandywine makes two arguments to the contrary. First, it contends that the ALJ failed
to consider that, while at Brandywine, Kennard did not spend every day blasting at coal mines,
and the limited number of days that he was exposed to coal dust at Brandywine render his work
there dissimilar to the work of an underground miner. This misconstrues the ALJ’s finding. The
ALJ found that when Kennard was working as a blaster on coal mines for Brandywine, his work
was substantially similar to the work of an underground miner. He did not consider, in counting
the fifteen years of substantially-similar conditions, the days that Kennard was not working as a
blaster. In other words, he treated Kennard as he would have treated a miner who spent the same
number of days in an underground mine, with the remaining days spent doing non-mining work.
Because the ALJ found Kennard to have more than 21 years of work under substantially similar
conditions, moreover, he would qualify for the presumption even if his work at Brandywine were
not counted.

       Second, Brandywine argues that Kennard was primarily exposed to rock dust and dirt,
rather than coal dust, and that he therefore should not be entitled to the presumption. In the
company’s words: “Since rock dusting is a recognized method for suppressing coal dust and is
used throughout the industry for this purpose, Kennard’s suggestion that rock dust presents a risk
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.          Page 10

of disease not only makes no sense, but it is supported by nothing.” Reply Br. at 14–15 n.5.
Brandywine further cites our dicta in Central Ohio Coal Co., that the distinction between coal
dust and dust from dirt “may be significant” in applying the 

.

       Brandywine’s proposed distinction between coal dust and rock dust has no merit.
Although it is true that the mandatory safety standards for underground mines require the use of
rock dusting to suppress coal dust, the rock dust is used to suppress the combustible nature of
coal dust and to prevent explosions. See 30 C.F.R. § 75.402. In the context of respiratory safety,
the standards explicitly regulate the concentrations of quartz dust—a type of rock dust—that may
be present. See 30 C.F.R. § 70.101; see also In re Howard, 

, 754–56 (6th Cir.
2009) (discussing this standard in further detail).        Furthermore, the definition of clinical
pneumoconiosis includes silicosis, a disease caused by rock dust (silica) and not coal dust. 20
C.F.R. § 718.201(a)(1). Rock dust is part of the respiratory hazard faced by underground coal
miners and was an appropriate consideration in determining whether Kennard’s working
conditions were similar to those in an underground mine. As in the Central Ohio case, the
record also supports a finding about coal dust alone. As a blaster, Kennard cleared away the
rock and dust that lay over coal deposits; he explicitly testified that he would periodically come
across thin seams of coal, leading to “clouds of smoke.”

       The record contains substantial evidence that Kennard was regularly exposed to both coal
and rock dust. He has therefore established that his working conditions were substantially
similar to those in an underground mine and is entitled to the presumption.

D.     Rebuttal

       Having found Kennard eligible for the 15-year presumption, the ALJ addressed rebuttal:
“As the Claimant has established the threshold requirements for invocation of the rebuttable
presumption, the burden shifts to the Employer to rebut the presumption by establishing either
(a) that the Claimant does not have pneumoconiosis; or (b) that his respiratory or pulmonary
impairment does not arise out of, or in connection with, coal mine employment.” The parties
now dispute the relationship of Kennard’s COPD to his exposure to coal-mine dust and the
extent to which his coal-mine employment contributed to his disability in light of his lung
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.          Page 11

removal for unrelated reasons. The ALJ considered three doctors’ opinions on these issues:
Dr. Mahmood Alam, Dr. Bruce C. Broudy, and Dr. Abdul K. Dahhan.

        Dr. Alam equivocally diagnosed Kennard with legal pneumoconiosis by virtue of his
COPD.     He acknowledged that the “number one cause” of the COPD was smoking but
maintained, with varying degrees of certainty, that coal-mine dust exposure likely contributed to
the disease. At various times, he described the dust exposure as responsible for “at least 10
percent” of Kennard’s disability, or “at least 15% of total pulmonary impairment,” or that it
“could have done some aggravation” of the emphysema. Dr. Alam also noted that Kennard’s
diminished lung capacity was significantly less than could be explained by the removal of his
lung, such that he may have been totally disabled even if his lung had not been removed.
Because of the equivocal nature of Dr. Alam’s opinion, the ALJ gave less weight to his opinion
on the legal-pneumoconiosis issue.

        Dr. Broudy opined that Kennard did not have pneumoconiosis and his disability was
therefore not related to his coal-mine employment. He noted Kennard’s diagnosis of COPD and
attributed the lung disease entirely to cigarette smoking. In deposition, he opined that “the
respiratory impairment is easily explained by the fact that this gentleman has had a right
pneumonectomy [lung removal] and damage to his lung from previous cigarette smoking” and
“[t]here was no evidence of pneumoconiosis in the remaining lung.” Dr. Broudy, however,
provided no other explanation for his opinion that coal-mine dust inhalation was not a factor
causing the COPD, and for this reason, the ALJ discredited his testimony.

        Dr. Dahhan noted that Kennard’s respiratory impairment resulted from the removal of his
right lung “which created anatomical loss of more than half of his respiratory capacity” and was
“contributed to by his previous smoking habit and resulting bronchitis [(COPD)].” He opined
that the degree of respiratory impairment was too severe to “be accounted for by the impact of
coal dust on the respiratory system.” He also noted that Kennard’s treating physician had
prescribed bronchodilators for the COPD. Because lung disease caused by inhalation of coal-
mine dust is not responsive to bronchodilators, he considered the prescription to be evidence that
dust inhalation had no causal role in the COPD. In deposition, he testified that 65% of the loss
of lung function could be attributed to the removal of the right lung.
No. 14-3672         Brandywine Explosives & Supply, et al. v. OWCP, et al.        Page 12

        The ALJ discounted Dr. Dahhan’s testimony on several grounds. First, he characterized
the opinions as internally inconsistent, due to the varying degree to which Dr. Dahhan
acknowledged the COPD and varied characterization of the impairment as obstructive or
restrictive.   Second, because several respiratory tests conducted by Dr. Dahhan and others
showed that Kennard’s disease was not responsive to bronchodilators, that aspect of the opinion
was not well-reasoned. Finally, Dr. Dahhan insufficiently accounted for the possibility that
Kennard’s respiratory problems had multiple causes, even though the most significant cause was
smoking and the resulting lung removal.

        The ALJ found that Brandywine rebutted the presumption of clinical pneumoconiosis,
but that the mixed evidence did not rebut the presumption of legal pneumoconiosis—the
presumption that Kennard’s COPD was caused, in part, by his coal-mine employment.
Addressing the causation issue, the ALJ noted that “an employer establishes rebuttal when it
shows that pneumoconiosis played no part in causing a miner’s disability or death.” D&O at 25
(citing Island Creek Coal Co. v. Holdman, 

, 882 (6th Cir. 2000), and other cases).
The ALJ discredited Dr. Dahhan’s and Dr. Broudy’s opinion on causation because they had not
found legal pneumoconiosis. Noting in particular Dr. Alam’s opinion that Kennard’s COPD was
so severe in his remaining lung that he would likely be totally disabled even had he never had
cancer, the ALJ found that Brandywine had not rebutted the presumption that Kennard’s
respiratory impairment—and disability—were caused by his coal mine employment.

        Brandywine argues that the ALJ used the improper rebuttal standard; that it rebutted the
presumption that Kennard has legal pneumoconiosis; and that it rebutted the presumption that
Kennard’s disability was caused by his coal-mine employment. None of these arguments is
availing.

        1.      Rebuttal Standard

        Brandywine first argues that the ALJ improperly limited its avenues of rebuttal. The
15-year presumption presumes three elements of a claim: (1) that the miner has pneumoconiosis,
(2) that the pneumoconiosis arose out of his coal-mine employment, and (3) that the miner’s total
disability is due to the pneumoconiosis. Brandywine contends that the ALJ limited his analysis
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.           Page 13

to the first two elements, without considering whether the pneumoconiosis was so mild that it did
not cause Kennard’s total disability.

       We have already addressed and rejected this argument. See Big Branch 

–71. There we began by noting the three elements of entitlement to benefits
that the 15-year presumption affects, 

then explained that a finding of legal
pneumoconiosis establishes the first two elements, leaving only the third, 

We found
that an ALJ “d[oes] not err by collapsing the two-step causal chain—that coal mine employment
caused pneumoconiosis which in turn caused total disability—into a single question: did the
miner’s disability arise out of his coal mine employment?” 

“that a miner’s
pneumoconiosis is mild and that the totally disabling respiratory impairment is the product of
another disease . . . is not a unique third rebuttal method, but merely a specific way to attack the
second link in the causal chain—that pneumoconiosis caused total disability.” 

case,
as in Big Branch Resources, “[n]othing in the record suggests that the [employer] was prevented
from making this argument.” 

further argues that the ALJ erred by requiring it to prove that Kennard’s
legal pneumoconiosis “played no part” in his disabling respiratory impairment, rather than
determining whether pneumoconiosis was a “substantially contributing cause.” We likewise
rejected this argument in Big Branch Resources:

       Simply put, the “play no part” or “rule-out” standard and the “contributing cause”
       standard are two sides of the same coin. Where the burden is on the employer to
       disprove a presumption, the employer must “rule-out” coal mine employment as a
       cause of the disability. Where the employee must affirmatively prove causation,
       he must do so by showing that his occupational coal dust exposure was a
       contributing cause of his disability. Because the burden here is on the [employer],
       the [employer] must show that the coal mine employment played no part in
       causing the total disability.

       The ALJ’s articulation of the rebuttal standard was appropriate.
No. 14-3672       Brandywine Explosives & Supply, et al. v. OWCP, et al.          Page 14

       2.     Rebuttal of Legal Pneumoconiosis

       Substantial evidence supports the ALJ’s finding that Brandywine failed to rebut the
presumption of legal pneumoconiosis. All three of the doctors who examined Kennard noted
that he has COPD. There was disagreement about whether the COPD was solely a result of his
cigarette smoking or was also caused or worsened by coal-mine dust. The ALJ found none of
the medical opinions to be persuasive on the issue. “Dr. Alam’s opinion is equivocal and vague;
Dr. Broudy gives no reason for excluding coal dust as a cause of the Claimant’s emphysema; and
Dr. Dahhan is inconsistent and not well-reasoned.”

       Focusing extensively on the uncontested issue of Kennard’s lung cancer and minimizing
the factual errors and inconsistencies in Dr. Dahhan’s opinions, Brandywine urges us to reverse
the ALJ’s credibility determinations for Dr. Broudy and Dr. Dahhan.          There is sufficient
evidence supporting the ALJ’s credibility determinations. Dr. Dahhan’s opinions contained a
number of leaps of logic, including ignoring the possibility that Kennard’s COPD could have
multiple causes—smoking and dust exposure. Dr. Dahhan’s opinion also relied on his belief that
the COPD was responsive to bronchodilators, but there was evidence before the ALJ that the
disease did not respond to bronchodilators. As for Dr. Broudy, his opinion relied only on the
lack of a finding of clinical pneumoconiosis, providing no explanation for why he did not believe
dust exposure played a role in the COPD.

       Brandywine also urges the court to weaken the presumption, so that Dr. Alam’s
equivocal opinion would be sufficient to rebut the presumption of legal pneumoconiosis. As we
noted in Morrison, however, rebuttal requires “that the evidence affirmatively proved the
absence of 

n.5. In the present case, there is evidence that
Kennard suffers from COPD in addition to his lung cancer. The only question is whether
smoking alone caused the COPD or whether it was also caused or worsened by the coal-mine
dust exposure. Dr. Alam, the only credible medical opinion on the issue, largely opined that the
COPD was partially caused by coal-mine dust exposure. Brandywine points to no affirmative
proof of the absence of pneumoconiosis, in Dr. Alam’s opinion evidence or elsewhere. The ALJ
did not err in finding that Brandywine failed to rebut the presumption of legal pneumoconiosis.
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.            Page 15

       3.      Rebuttal of Causation

       Brandywine next argues that the ALJ erred in finding that the causation element was not
rebutted. The employer first argues that the ALJ failed to consider this issue, instead treating the
causation issue as automatically resolved by the failure to rebut the presumption of legal
pneumoconiosis. In fact, the ALJ considered this issue carefully, reviewing the opinions of all
three doctors. Each doctor opined that Kennard’s impairment was more severe than could be
explained solely by the removal of his right lung. The ALJ relied on these opinions, and
particularly Dr. Alam’s opinion that Kennard’s respiratory capacity was so low that he may have
been disabled even with both lungs. At that juncture, the only remaining question was what
caused the additional respiratory impairment—an issue resolved by the earlier finding of legal
pneumoconiosis. There was no need for the ALJ to analyze the opinions a second time.

       Brandywine insists that, because Kennard would be totally disabled had he never set foot
in a mine (due to his lung cancer and lung removal), it would be unfair to hold the company
responsible for his disability. The implementing regulations and our long-standing precedent
have rejected this view of the causation requirement. Since 2000, the regulations have made
clear that, even when a claimant bears the burden of proof, he must show only that
pneumoconiosis was a “substantially contributing cause” of the disability, a standard that is met
if pneumoconiosis “[h]as a material adverse effect on the miner’s respiratory or pulmonary
condition; or [m]aterially worsens a totally disabling respiratory or pulmonary impairment which
is caused by a disease or exposure unrelated to coal mine employment.”                   20 C.F.R.
§ 718.204(c)(1). In defining this standard, the Department relied in part on our court’s reasoning
in Cross Mountain Coal, Inc. v. Ward, 

(6th Cir. 1996).                 See Regulations
Implementing the Federal Coal Mine Health and Safety Act of 1969, as Amended, 65 Fed. Reg.
79,920, 79,946–47 (2000). In Cross Mountain, we expressly rejected Brandywine’s argument:

       A review of the cases, the statute, its legislative history, and its interpretation by
       the benefits review board shows that the statute is intended to confer special
       benefits on miners who are disabled due to pneumoconiosis whether or not they
       are disabled from a different cause. Even when other causes are themselves
       independently disabling the concurrence of two sufficient disabling medical
       causes one within the ambit of the Act, and the other not, will in no way prevent a
       miner from claiming benefits under the Act.
No. 14-3672        Brandywine Explosives & Supply, et al. v. OWCP, et al.         Page 

(internal quotation marks and alterations omitted). Notably, Brandywine relies
almost exclusively on cases decided before the “substantially contributing cause” standard was
promulgated in 2000. (One of these cases, Shelton v. Dir., Office of Workers’ Comp. Programs,

(7th Cir. 1990), was explicitly rejected in Cross Mountain. 

.)

        The ALJ did not err in finding that Brandywine failed to rebut the 15-year presumption of
eligibility.

                                    IV.     CONCLUSION

        For the foregoing reasons, we DENY the petition for review.