                           In the
 United States Court of Appeals
                For the Seventh Circuit
                        ____________

Nos. 01-2508 & 01-3059
PEABODY COAL COMPANY and
OLD REPUBLIC INSURANCE COMPANY,
                                                    Petitioners,
                              v.


ESTATE OF J.T. GOODLOE, Larry
Goodloe, Personal Representative, and
SHELBY HALLMARK, Acting Director,
Office of Workers’ Compensation Programs,
                                                  Respondents.
                        ____________
                 Petitions to Review Orders of the
    Benefits Review Board, United States Department of Labor
                         No. 00 BLA 0676
                        ____________
    ARGUED APRIL 5, 2002—DECIDED AUGUST 12, 2002
                     ____________


 Before FLAUM, Chief Judge, POSNER and ROVNER, Circuit
Judges.
  ROVNER, Circuit Judge. Peabody Coal Company and Old
Republic Insurance Company (collectively “Peabody”) ap-
peal from orders entered by the Benefits Review Board
(“BRB”) in favor of the Estate of J.T. Goodloe. The BRB
affirmed an award to Goodloe of black lung benefits and
an award of fees to his attorney, who has pursued this
2                                   Nos. 01-2508 & 01-3059

claim for Goodloe and now for his estate for approximately
twenty-four years. We previously remanded because the
Administrative Law Judge applied an incorrect legal stan-
dard in determining whether to invoke an interim presump-
tion that Goodloe suffered from a coal-related impairment.
See Peabody Coal Co. v. Goodloe, 116 F.3d 207 (7th Cir.
1997). On remand, the ALJ applied the standard we set
out and again concluded that Goodloe was entitled to ben-
efits. We now affirm.


                             I.
  We will assume familiarity with our earlier opinion
and will repeat only those facts necessary to the disposi-
tion of this successive appeal. Goodloe worked in the
coal mines for more than thirty years. In 1978, he filed a
claim for black lung benefits. Because of the length of
time that he worked in the mines, Goodloe was entitled
to an interim presumption of total disability due to pneu-
moconiosis (commonly known as black lung disease) if
he could meet any of the criteria set forth in 20 C.F.R.
§ 727.203(a). The only criterion at issue at this point in the
proceedings is subsection (a)(3), which provides, in rele-
vant part, that a miner will be presumed to be totally
disabled due to pneumoconiosis if he can demonstrate
the following medical condition by a preponderance of the
evidence:
    Blood gas studies which demonstrate the presence of
    an impairment in the transfer of oxygen from the
    lung alveoli to the blood as indicated by values which
    are equal to or less than the values specified [in an
    attached table].
20 C.F.R. § 727.203(a)(3). Goodloe’s physicians conducted
two studies of his blood gas levels, one in 1979 and one in
1984. The 1979 study produced non-qualifying results but
the 1984 study was well within the qualifying range. In-
Nos. 01-2508 & 01-3059                                         3

deed, the 1984 study indicated theat Goodloe was suffer-
ing severe oxygen deprivation. Goodloe’s blood oxygen lev-
els were so low that every physician reviewing the results
initially questioned the validity of the study.
  In our prior opinion, we remanded the case because the
ALJ placed an impermissible burden on the employer in
determining whether to invoke the interim presumption.
Rather than placing the burden of proof for the validity
of the blood gas study on Goodloe, the ALJ invoked the
presumption because Peabody failed to produce evidence
that would invalidate the study. Goodloe, 116 F.3d at 212.
On remand, we held that Goodloe was entitled to the in-
terim presumption only if he could show by a preponder-
ance of the evidence that the 1984 blood gas study was
valid. Id. If Goodloe was able to show he was entitled to
the presumption, Peabody would then have an opportunity
to rebut the presumption using the methods set forth in
section 727.203(b).
   On remand, the ALJ considered the 1984 blood gas study
ordered and reviewed by Dr. Henry Peters. Dr. Peters con-
ducted a thorough physical examination of Goodloe at
that same time and also ordered other diagnostic tests.
When he received the results of the blood gas study, Dr.
Peters asked the lab to double-check the test and verify
it for accuracy, which the lab did to the doctor’s satisfac-
tion. The ALJ noted that Dr. Peters’ physical examination
of Goodloe and another diagnostic test corroborated the re-
sults of the blood gas study. At the examination, Goodloe
appeared short of breath without exertion. He also exhi-
bited increased chest diameter and clubbing of the digits.1
Another blood test conducted at that time indicated that


1
  Clubbing of the digits refers to a broadening and thickening of
the fingers or toes with increased lengthwise curvature and
curvature of the tip of the nail, with flattening of the angle
between the cuticle and nail. See www.nlm.gov/medlineplus/ency/
article/003282.htm.
4                                  Nos. 01-2508 & 01-3059

Goodloe had a condition known as polycythemia, or exces-
sive red blood cells. This condition develops as a reaction
to severe oxygen deficiency. All of these physical find-
ings are consistent with black lung disease. Although two
other physicians (Drs. Frank Stewart and David Howard)
who subsequently reviewed the results doubted the valid-
ity of the qualifying blood gas study, the ALJ noted that
neither had examined the miner, and the employer had
produced no evidence suggesting the test results were in-
valid. Because Goodloe produced evidence that corrobo-
rated the validity of the study, the ALJ invoked the pre-
sumption under section 727.203(a)(3).
  The ALJ proceeded to analyze whether Peabody could
rebut the presumption under section 727.203(b). Under
that section, the employer could rebut the presumption
by demonstrating that (1) the miner was in fact perform-
ing his usual coal mine work or comparable, gainful work;
(2) the miner was able to perform his usual coal mine work
or comparable, gainful work; (3) the miner’s total disabil-
ity or death did not arise in whole or in part out of coal
mine employment; or (4) the miner does not or did not
have pneumoconiosis. The ALJ found no rebuttal evidence
under the first prong of the test; Goodloe had stopped work-
ing in the mines and subsequently died.
  Under the second prong, the ALJ found the medical
evidence submitted by Peabody insufficient to establish
by a preponderance of the evidence that Goodloe was
capable of performing his usual coal mine or other compara-
ble and gainful work. The ALJ rejected the medical opin-
ions of Drs. Vest, Renn and Tuteur because they related
exclusively to a 1979 pulmonary function study that did
not produce qualifying results. In reviewing the opinions
of Drs. Howard and Stewart, the ALJ considered wheth-
er Peabody could show that Goodloe was not disabled
from performing his usual coal mine work despite the val-
id 1984 blood gas test. On that rebuttal point, the ALJ
Nos. 01-2508 & 01-3059                                    5

noted, the employer could not rely on evidence already
considered and rejected in the invocation of the presump-
tion. The ALJ thus refused to reconsider the opinions of
Drs. Howard and Stewart questioning the validity of the
1984 blood gas study. That left the employer with Dr.
Howard’s opinion that coronary artery disease could have
produced the shortness of breath that Goodloe experi-
enced, and Dr. Stewart’s opinion that Goodloe’s continued
cigarette smoking would have contributed to his failing
health between the 1979 test and the 1984 test. Neither
Dr. Stewart nor Dr. Howard testified as to the degree
of impairment that would be expected if they presumed
the 1984 blood gas study was valid. The ALJ thus found
that Peabody failed to produce sufficient evidence on the
second rebuttal prong.
  On the third prong, the ALJ considered whether Pea-
body had shown by a preponderance of the evidence that
black lung disease was not a contributing cause to Good-
loe’s disability. Goodloe had smoked cigarettes all of his
adult life, and Peabody maintained that tobacco and not
coal was the source of his lung problems. The ALJ found
inadequate support for this argument in the record, ruling
that none of the physicians testifying convincingly ruled
out coal dust exposure as a contributing cause for Good-
loe’s disability. Finally, the ALJ contemplated Peabody’s
evidence on the fourth prong, whether Goodloe suffered
from pneumoconiosis. The employer submitted x-rays and
the opinions of Drs. Howard and Stewart. Although the
ALJ agreed that the x-rays did not support a finding of
pneumoconiosis, he also found that negative x-rays alone
cannot establish the absence of the disease. The ALJ found
that the opinions of Drs. Howard and Stewart did not
adequately explain why thirty-three years of coal dust
exposure was not a factor in Goodloe’s lung disease. Accord-
ingly, the ALJ found that Peabody had failed to adequate-
ly rebut the presumption of total disability due to coal
6                                 Nos. 01-2508 & 01-3059

dust exposure and granted Goodloe’s claim for benefits.
Subsequently, the Benefits Review Board affirmed the
ALJ’s award of benefits and found that Goodloe’s coun-
sel was entitled to fees totaling $2300, representing 11.5
hours of work at a rate of $200 per hour. Peabody appeals.


                            II.
  Although Peabody appeals the decision of the BRB, this
court reviews the decision of the ALJ, not the BRB. Good-
loe, 116 F.3d at 211; Consolidation Coal Co. v. Office of
Workers’ Compensation Programs, 54 F.3d 434, 436 (7th
Cir. 1995). We will not overturn an ALJ’s decision if it
is rational, supported by substantial evidence and consis-
tent with the governing law. Goodloe, 116 F.3d at 211.
Substantial evidence is that which a reasonable mind
might accept as adequate to support a conclusion. Id.
Moreover, in reviewing the decision of the ALJ, we will not
reweigh the evidence or substitute our judgment for that
of the ALJ. Id. Peabody challenges both the ALJ’s invoca-
tion of the presumption under section 727.203(a)(3) and
the ALJ’s holding that Peabody failed to meet the stan-
dard for rebuttal under section 727.203(b)(3). Peabody
also contests the attorney’s fee awarded to Goodloe’s coun-
sel, objecting that there was an inadequate basis for the
hourly rate requested.
  Peabody challenges the ALJ’s invocation of the interim
presumption with the testimony of Drs. Howard and
Stewart. Both physicians testified that they would view
Goodloe’s blood gas results with suspicion and would
probably have the test repeated rather than accept the
results at face value. Dr. Peters himself initially doubted
the validity of the test and called the laboratory conduct-
ing the test to verify the result. The laboratory validated
the test to Dr. Peters’ satisfaction. Moreover, Goodloe ex-
hibited shortness of breath without exertion, an expanded
Nos. 01-2508 & 01-3059                                     7

chest diameter, clubbing of the digits, and polycythemia, or
excessive red blood cells. Polycythemia develops as a
reaction to severe oxygen deficiency. All of these conditions
corroborated the results of the blood gas test. The ALJ thus
concluded that Goodloe had proved by a preponderance
of the evidence that a valid blood gas study met the qual-
ifying levels set by section 727.203(a)(3), and Goodloe
was thus entitled to the interim presumption of total
disability due to pneumoconiosis. Mullins Coal Co., Inc.
of Virginia v. Director, O.W.C.P., U.S. Dept. of Labor,
484 U.S. 135, 159 (1987). In short, the ALJ’s decision
to invoke the interim presumption based on the 1984
blood gas study was rational, supported by substantial
evidence and consistent with the governing law. Peabody’s
argument amounts to a request that we reweigh the
evidence, which we may not do. Consolidation Coal, 54 F.3d
at 436.
  Peabody argues in the alternative that, even if Goodloe
was entitled to the interim presumption, the ALJ erred in
ruling that Peabody failed to rebut the presumption under
section 727.203(b)(3). That section provides that the em-
ployer may rebut the interim presumption by demonstrat-
ing that the total disability or death of the miner did
not arise in whole or in part out of coal mine employ-
ment. 20 C.F.R. § 727.203(b)(3); Old Ben Coal Co. v. Di-
rector, O.W.C.P., U.S. Dept. of Labor, 62 F.3d 1003, 1008
(7th Cir. 1995). The employer may meet its burden un-
der this section by showing that the miner’s pneumoconi-
osis was not a contributing cause of his total disability.
Old Ben Coal Co., 62 F.3d at 1008. A “contributing cause”
means coal dust exposure was a necessary, though not
necessarily sufficient, cause of a miner’s disability. Id.
To meet this standard, the employer must demonstrate
by a preponderance of the evidence that pneumoconiosis
was in no way related to the claimant’s disability. Id.
 Peabody attempts to meet this standard by arguing that
Goodloe’s disability was due solely to his history of ciga-
8                                   Nos. 01-2508 & 01-3059

rette smoking. Peabody cites the opinion of Dr. Howard
that Goodloe suffered from an obstructive rather than
restrictive impairment of lung function. Dr. Howard opined
that smoking-related emphysema was thus the more likely
cause of Goodloe’s impairment. The ALJ rejected this evi-
dence because Dr. Howard failed to explain how thirty-
three years of coal dust exposure did not contribute to
Goodloe’s lung impairment, especially because emphysema
comes within the legal definition of pneumoconiosis. Pea-
body also relies on Dr. Stewart’s opinion that, in 1979,
Goodloe suffered only mild coronary artery disease brought
on by cigarette smoking. The ALJ noted, however, that
Dr. Stewart offered no opinion as to the etiology of Good-
loe’s lung impairment, either on direct or cross-exam-
ination. The ALJ reasoned that Dr. Stewart’s diagnosis
of mild coronary artery disease did not rebut the presump-
tion because Dr. Stewart never addressed whether coal
dust was a contributing cause of Goodloe’s impairment.
The ALJ correctly noted that the employer could not rely
on evidence introduced and rejected during the invoca-
tion analysis. Mullins Coal, 484 U.S. at 150 n.26. The
ALJ concluded that Peabody failed to prove its case for
rebuttal with a preponderance of the evidence. Peabody
again suggests that we reweigh the evidence and conclude
that Goodloe’s impairment was due to cigarette smok-
ing rather than coal dust exposure. Peabody’s evidence is
rather thin, though, and it is not our function to substitute
our own judgment for that of the ALJ. Consolidation Coal,
54 F.3d at 436. The ALJ’s conclusion was rational, sup-
ported by substantial evidence and not contrary to the law
of this circuit. We therefore affirm the judgment.
  The only issue that remains is Peabody’s objection to
the amount of fees awarded to Goodloe’s attorney, Jack
VanStone. Peabody maintains that VanStone’s request
for $200 per hour for his work on this case is not based
on his customary rate and is not based on a reasonable
Nos. 01-2508 & 01-3059                                     9

rate. Under 30 U.S.C. § 932(a), an attorney for a success-
ful claimant for black lung benefits is entitled to a reason-
able attorney’s fee. See United States Dept. of Labor v.
Triplett, 494 U.S. 715, 717-18 (1990). The fee requested
must be approved by the appropriate agency or court. Id.
The fee awarded is to be “reasonably commensurate
with the necessary work done,” taking into account the
quality of the representation, the qualifications of the at-
torney, the complexity of legal issues involved, the level
of proceedings to which the claim was raised, the level
at which the attorney entered the proceedings, and any
other information which may be relevant to the amount
of the fee requested. Triplett, 494 U.S. at 718; 20 C.F.R.
§ 725.366. Moreover, the rate at which the attorney is
compensated must be market-based. Peabody Coal Co. v.
McCandless, 255 F.3d 465, 470 (7th Cir. 2001).
  VanStone submitted his request for fees to the BRB,
asking for $200 per hour for 11.5 hours of work. In his
petition, VanStone represented that $200 was his “usual
billing rate per hour.” In another case in which VanStone
sought fees in the same time frame, he noted nineteen
other occasions when this rate had been approved for
his work in black lung cases by various administrative
law judges, the BRB, and by this Court. The BRB re-
viewed VanStone’s itemized statement of fees, found the
amount requested reasonable in light of the services
performed, and corrected a small mathematical error in
VanStone’s fee petition. The BRB awarded a total of
$2300. Peabody concedes that VanStone is well-versed in
federal black lung law and quite experienced in represent-
ing black lung claimants. In response to VanStone’s repre-
sentation that $200 per hour is his usual billing rate,
Peabody states that it “reasonably believes that Mr.
VanStone’s ‘customary billing rate’ is substantially less
than $200 per hour even at this time.” Opening Brief at
37 n.24. This statement is pure speculation, however,
10                                Nos. 01-2508 & 01-3059

and speculation is insufficient to challenge the BRB’s
finding that VanStone’s usual billing rate was reasonable
given the work he performed below. Given VanStone’s fee
recoveries in a number of similar cases, his representa-
tion that this is his usual fee, and the absence of any
contrary information regarding the market rate from
Peabody, we affirm the BRB’s award of fees.
                                              AFFIRMED.

A true Copy:
      Teste:

                      ________________________________
                      Clerk of the United States Court of
                        Appeals for the Seventh Circuit




                  USCA-97-C-006—8-12-02
