                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

DEPARTMENT OF THE TREASURY -         
INTERNAL REVENUE SERVICE,
                       Petitioner,
               v.
                                         No. 05-76031
FEDERAL LABOR RELATIONS
AUTHORITY,
                                        No. 61 FLRA
                                           NO. 30
                     Respondent,
NATIONAL TREASURY EMPLOYEES
UNION,
                      Intervenor.
                                     

FEDERAL LABOR RELATIONS              
AUTHORITY,
                      Petitioner,
                                         No. 05-76391
               v.
DEPARTMENT OF THE TREASURY -            No. 61 FLRA
                                           NO. 30
INTERNAL REVENUE SERVICE;
                                          OPINION
NATIONAL TREASURY EMPLOYEES
UNION,
                    Respondents.
                                     
        On Petition for Review of an Order of the
           Federal Labor Relations Authority

                 Argued and Submitted
       December 5, 2007—San Francisco, California

                   Filed April 3, 2008

                           3501
3502             DEP’T OF THE TREASURY v. FLRA
Before: Alex Kozinski, Chief Judge, Robert E. Cowen,* and
          Michael Daly Hawkins, Circuit Judges.

                    Opinion by Judge Cowen




   *The Honorable Robert E. Cowen, Senior United States Circuit Judge
for the Third Circuit, sitting by designation.
3504           DEP’T OF THE TREASURY v. FLRA


                        COUNSEL

William G. Kanter, Esq., Christine N. Kohl, Esq., U.S.
Department of Justice, Washington, D.C., for the petitioner-
respondent.

David M. Smith, William R. Tobey, Esq., David M. Shew-
chuk, Esq., and James F. Blandford, Esq., Federal Labor Rela-
tions Authority, Washington, D.C., for the respondent-
petitioner.

Barbara A. Atkin, Esq., Julie M. Wilson, Esq., Gregory
O’Duden, Esq., National Treasury Employers Union, Wash-
ington, D.C., for the intervenor.


                         OPINION

COWEN, Circuit Judge:

   The Department of Treasury, Internal Revenue Service
(“IRS”), petitions this court to review an August 10, 2005,
order by the Federal Labor Relations Authority (“FLRA”).
The FLRA, along with the intervenor, the National Treasury
Employees Union (“NTEU”), has cross-petitioned this court
to enforce the FLRA’s order. For the following reasons, we
will deny the IRS’s petition for review and grant the FLRA’s
cross-petition for enforcement.
                   DEP’T OF THE TREASURY v. FLRA          3505
              I.     FACTUAL BACKGROUND

   The facts underlying this case are not in dispute. In 1998,
the IRS temporarily assigned revenue officers and revenue
agents from its Tacoma, Everett, and Bellevue, Washington
offices to work at the Seattle district headquarters. These
employees assisted with walk-in and telephone customers.

   At all times relevant to this case, the IRS and the NTEU
operated under a collective bargaining agreement (“CBA”).
Article 29, Section 3E of the CBA stated that, “[w]hen an
employee travels from his/her residence to a point of destina-
tion within his/her official duty station, he/she should not be
required to leave home any earlier or arrive home any later
than he/she does when he/she travels to and from his/her usual
assigned place of business.” The Tacoma, Everett, Bellevue,
and Seattle offices were all located within the same official
duty station.

   The NTEU filed a grievance asserting that the IRS failed to
compensate the transferred employees for their increased
commute time in violation of Article 29, Section 3E of the
CBA. In July 2000, the arbitrator found that Article 29, Sec-
tion 3E applied to the affected employees. The arbitrator also
determined that the provision would allow for compensation
for the extra commute time. Furthermore, the arbitrator found
that the CBA provision constituted an “express provision,”
which permitted compensation to these federal employees
under the Portal-to-Portal Act, 29 U.S.C. §§ 251-262. The
arbitrator stated that the IRS “violated the FLSA [Fair Labor
Standards Act, 29 U.S.C. §§ 201-219] by not permitting
employees to travel to and from the Seattle Jackson Federal
Building in accordance with the procedure required by Article
29, Section 3E.” Thus, the arbitrator sustained the grievance
and ordered the IRS to cease and desist from failing or refus-
ing to implement Article 29, Section 3E of the CBA.
3506               DEP’T OF THE TREASURY v. FLRA
   The IRS filed exceptions to the arbitrator’s award with the
FLRA. Before the FLRA, the IRS raised several arguments:
(1) the arbitrator’s award was contrary to law because 5
C.F.R. § 551.422(b)1 prohibited federal employees from being
compensated for commute time; (2) Article 29, Section 3E of
the CBA fell short of being the type of “express provision” of
a contract necessary to fall under 29 U.S.C. § 254(b)(1) of the
Portal-to-Portal Act; and (3) Article 29, Section 3E was not
a clear statement of an agreement to allow payment to
affected employees for their commute time. The FLRA
denied the exceptions. United States Dep’t of Treasury Inter-
nal Revenue Serv., 57 F.L.R.A. 444, 2001 WL 950798 (2001).
It rejected the latter two arguments on the merits. With
respect to the first argument, the FLRA concluded that the
IRS had failed to make this argument to the arbitrator. Thus,
pursuant to 5 C.F.R. § 2429.5,2 the FLRA refused to consider
this new argument on appeal of the arbitrator’s award.

  After the FLRA denied the exceptions, the IRS refused to
implement the arbitrator’s award. As a result, the NTEU filed
an unfair labor practice charge. The NTEU asserted that the
IRS failed to comply with the arbitrator’s award as required
by 5 U.S.C. § 7121 and § 7122. It argued that this constituted
an unfair labor practice under 5 U.S.C. § 7116(a)(1), (8). Ini-
  1
   5 C.F.R. § 551.422(b) states that:
     An employee who travels from home before the regular workday
     begins and returns home at the end of the workday is engaged in
     normal “home to work” travel; such travel is not hours of work.
     When an employee travels directly from home to a temporary
     duty location outside the limits of his or her official duty station,
     the time the employee would have spent in normal home to work
     travel shall be deducted from hours of work as specified in para-
     graphs (a)(2) and (a)(3) of this section.
  2
    5 C.F.R. § 2429.5 states that, “[t]he Authority will not consider evi-
dence offered by a party, or any issue, which was not presented in the pro-
ceedings before the Regional Director, Hearing Officer, Administrative
Law Judge, or arbitrator. The Authority may, however, take official notice
of such matters as would be proper.”
                DEP’T OF THE TREASURY v. FLRA              3507
tially, the FLRA determined that the NTEU’s unfair labor
practice charge was untimely. However, the D.C. Circuit
reversed and remanded the matter back to the FLRA for con-
sideration on the merits. See Nat’l Treasury Employees Union
v. Fed. Labor Relations Auth., 392 F.3d 498, 501 (D.C. Cir.
2004).

   On remand, the IRS did not dispute that it failed to imple-
ment the arbitrator’s award. However, it argued that it did not
commit an unfair labor practice because implementing the
arbitrator’s award would have required the IRS to engage in
an illegal act of compensating the affected employees for their
travel time. Specifically, the IRS asserted that the doctrine of
sovereign immunity precluded an order of monetary relief
absent a showing of an express waiver by the United States.
Once again, the IRS argued that 5 C.F.R. § 551.422 precluded
paying the employees for their commute time.

   The FLRA considered the sovereign immunity argument on
the merits after noting that the issue could be raised at any
time. The FLRA determined that 5 C.F.R. § 551.422 had no
affect on the sovereign immunity issue because 29 U.S.C.
§ 254(b) waived the government’s sovereign immunity under
the circumstances of this case. Therefore, the FLRA deter-
mined that the arbitrator’s award was enforceable, and that the
IRS violated 5 U.S.C. § 7116(a)(1), (8) by failing to comply
with the arbitrator’s award. It ordered the IRS to cease and
desist from failing to comply with the arbitrator’s award. The
FLRA ordered that: “(1) bargaining unit employees who were
required to travel outside their normal tour of duty to their
temporary duty assignment be identified, including the length
of their temporary assignment; and (2) affected bargaining
unit employees be compensated for time spent commuting to
their temporary duty assignment.” The IRS brought this peti-
tion for review order and the FLRA cross-petitioned for
enforcement of its order.
3508             DEP’T OF THE TREASURY v. FLRA
II.    APPELLATE JURISDICTION AND STANDARD OF
                      REVIEW

   This Court has appellate jurisdiction over the FLRA’s order
pursuant to 5 U.S.C. § 7123(a). “[W]e will set aside only
FLRA decisions that are ‘arbitrary, capricious, an abuse of
discretion, or otherwise not in accordance with the law.’ ”
Nat’l Treasury Employees Union (NTEU) v. Fed. Labor Rela-
tions Auth., 418 F.3d 1068, 1071 n.5 (9th Cir. 2005) (quoting
5 U.S.C. § 706(2)(A)). We review de novo the FLRA’s inter-
pretation of a statute that it does not administer. See id. (cita-
tions omitted); see also United States Dep’t of Air Force v.
Fed. Labor Relations Auth., 952 F.2d 446, 450 (D.C. Cir.
1991) (noting that no deference is accorded to FLRA’s inter-
pretation of the FLSA because “Congress specifically dele-
gated to the [Office of Personnel Management] the authority
‘to administer’ ” the Act’s provisions on overtime pay).

                      III.   DISCUSSION

   The issue presented in this case is whether the FLRA’s
award of compensation to those affected employees was in
error because it violated the United States’ sovereign immu-
nity. The parties dispute whether the United States has waived
sovereign immunity under the Portal-to-Portal Act. The IRS
asserts that the Portal-to-Portal Act does not expressly waive
sovereign immunity. The FLRA and the NTEU counter by
arguing that the Portal-to-Portal Act must be read as a com-
plement to the FLSA under these circumstances.

A.     Sovereign Immunity, the FLSA and the Portal-to-Portal
                              Act

   [1] We will consider the issue of sovereign immunity on
the merits because it can be raised at any time by the govern-
ment, as it goes to a court’s jurisdiction. See Settles v. United
States Parole Comm’n, 429 F.3d 1098, 1105 (D.C. Cir. 2005)
(citing Brown v. Sec’y of Army, 78 F.3d 645, 648 (D.C. Cir.
                    DEP’T OF THE TREASURY v. FLRA                      3509
1996)). Indeed, as the Supreme Court has noted, “[i]t is axi-
omatic that the United States may not be sued without its con-
sent and that the existence of consent is a prerequisite for
jurisdiction.” United States v. Mitchell, 463 U.S. 206, 212
(1983).

   [2] The waiver of the United States’ sovereign immunity
must be unequivocally expressed in the statutory text and will
not be implied. See Lane v. Pena, 518 U.S. 187, 192 (1996).
Furthermore, “a waiver of the Government’s sovereign immu-
nity will be strictly construed, in terms of its scope, in favor
of the sovereign.” Id. (citing United States v. Williams, 514
U.S. 527, 531 (1995); Library of Cong. v. Shaw, 478 U.S.
310, 318 (1986); Lehman v. Nakshian, 453 U.S. 156, 161
(1981)). Additionally, “[a] statute’s legislative history cannot
supply a waiver that does not appear clearly in any statutory
text; ‘the ‘unequivocal expression’ of elimination of sover-
eign immunity that we insist upon is an expression in statu-
tory text.’ ” Id. (quoting United States v. Nordic Vill., Inc.,
503 U.S. 30, 37 (1992)).

   [3] The FLSA was enacted in 1938, and, among other
things, granted covered employees statutory rights to overtime
compensation. See 29 U.S.C. § 207. These rights are enforce-
able under the FLSA through various remedies, as stated at 29
U.S.C. § 216.3 In Anderson v. Mt. Clemens Pottery Co., 328
U.S. 680, 690-91 (1946), the Supreme Court defined “work-
  3
   29 U.S.C. § 216(b) states that:
      Any employer who violates the provisions of section 206 or sec-
      tion 207 of this title shall be liable to the employee or employees
      affected in the amount of their unpaid minimum wages, or their
      unpaid overtime compensation, as the case may be, and in an
      additional equal amount as liquidated damages . . . . An action to
      recover the liability prescribed in either of the preceding sen-
      tences may be maintained against any employer (including a pub-
      lic agency) in any Federal or State court of competent jurisdiction
      by any one or more employees for and in behalf of himself or
      themselves and other employees similarly situated.
3510            DEP’T OF THE TREASURY v. FLRA
week” to include the time spent by employees walking from
their time clocks to their workstations. In response to Ander-
son, Congress passed the Portal-to-Portal Act in 1947. See 29
U.S.C. § 251(a) (finding that the FLSA “has been interpreted
judicially in disregard of long-established customs, practices,
and contracts between employers and employees”). The Act
pared back the definition of “workweek” set forth in Ander-
son. Indeed, as one court has noted with respect to the Portal-
to-Portal Act:

    [w]alking, riding, or traveling to and from the actual
    place of performance of the principal activity or
    activities which such employee is employed to per-
    form, and activities which are preliminary to or
    postliminary to said principal activity or activities
    are excluded from FLSA’s protections by the Portal-
    to-Portal Act; employers need not pay employees
    overtime . . . for such activity.

Adams v. United States, 471 F.3d 1321, 1325 (Fed. Cir. 2006)
(internal quotation marks omitted), cert. denied, 128 S. Ct.
866 (2008).

  [4] However, the Portal-to-Portal Act carved out two
exceptions, which do not relieve an employer from paying
overtime; specifically:

    Notwithstanding the provisions of subsection (a) of
    this section which relieve an employer from liability
    and punishment with respect to any activity, the
    employer shall not be so relieved if such activity is
    compensable by either —

    (1) an express provision of a written or nonwritten
    contract in effect, at the time of such activity,
    between such employee, his agent, or collective-
    bargaining representative and his employer; or
                DEP’T OF THE TREASURY v. FLRA                 3511
    (2) a custom or practice in effect, at the time of
    such activity, at the establishment or other place
    where such employee is employed, covering such
    activity, not inconsistent with a written or nonwritten
    contract, in effect at the time of such activity,
    between such employee, his agent, or collective-
    bargaining representative and his employer.

29 U.S.C. § 254(b). Additionally, the Portal-to-Portal Act
states that when the terms “employee” and “employer” are
used in relation to the FLSA, they each have the same mean-
ing as defined under the FLSA. See 29 U.S.C. § 262(a).

  In 1974, Congress amended the FLSA by expanding the
definition of “employee,” and the statute states that:

    In the case of an individual employed by a public
    agency, such term means —

    any individual employed by the Government of the
    United States —

    (i) as a civilian in the military departments (as
    defined in section 102 of Title 5),

    (ii) in any executive agency (as defined in section
    105 of such title),

    (iii) in any unit of the judicial branch of the Gov-
    ernment which has positions in the competitive ser-
    vice,

    (iv) in a nonappropriated fund instrumentality
    under the jurisdiction of the Armed Forces,

    (v)    in the Library of Congress, or

    (vi)   the Government Printing Office[.]
3512            DEP’T OF THE TREASURY v. FLRA
Id. § 203(e)(2)(A). Thus, “Congress extended the Act to cover
most government employees.” El-Sheikh v. United States, 177
F.3d 1321, 1323 (Fed. Cir. 1999). Government employees
were given the right to sue for violations of the FLSA, includ-
ing those pertaining to overtime compensation. See id. By
authorizing suits against the United States, the amendment
waives the government’s sovereign immunity. See id. at 1324
(citing Saraco v. United States, 61 F.3d 863, 865-66 (Fed. Cir.
1995); Cosme Nieves v. Deshler, 786 F.2d 445, 449 (1st Cir.
1986)).

  No party disputes that the FLSA waives the United States’
sovereign immunity. Instead, the IRS argues that the FLSA is
not applicable in this case and that the Portal-to-Portal Act
does not expressly waive sovereign immunity. For the follow-
ing reasons, we disagree.

   In Lane, the Supreme Court analyzed whether the United
States waived sovereign immunity under 29 U.S.C. § 794(a)
of the Rehabilitation Act of 1973. 518 U.S. at 189. The
Supreme Court specifically looked at the remedies provision
of the statute in determining that the United States had not
waived sovereign immunity. See 518 U.S. at 192-93. There-
fore, in determining whether the United States has waived
sovereign immunity in this case, we will examine the reme-
dies provision of the statute.

   [5] As previously noted, this case was brought on behalf of
affected employees seeking overtime pursuant to Article 29,
Section 3E of the CBA. Indeed, the arbitrator recognized that
the IRS violated the FLSA in not complying with the CBA
provision. Under these circumstances, the Portal-to-Portal
Act’s exception under 29 U.S.C. § 254(b)(1) must be read in
conjunction with the FLSA. Cf. Astor v. United States, 79
Fed. Cl. 303, 319 (2007) (noting that the Back Pay Act and
the FLSA should be read as complementary where plaintiffs
sought interest on their back pay awards, not on liquidated
damages); Adams v. United States, No. 00-447C, 2003 WL
                    DEP’T OF THE TREASURY v. FLRA                     3513
22339164, at *1 (Fed. Cl. Aug. 11, 2003) (noting that claims
for back pay under the FLSA are governed by the Portal-to-
Portal Act’s statute of limitations), aff’d, 391 F.3d 1212 (Fed.
Cir. 2004). The relevant remedies provision for overtime pro-
tections is found within the FLSA. See 29 U.S.C. § 216.

   [6] This is a case that concerns overtime. The FLSA has
always governed overtime, and although NTEU supports its
claim for overtime compensation by invoking the Portal-to-
Portal Act, we nevertheless look to the FLSA’s remedies pro-
vision to determine whether the government waived its sover-
eign immunity. See Adams v. United States, 48 Fed. Cl. 602,
609 (2001) (noting that in the case of overtime pay under the
FLSA, the statute itself provides the remedy and that the
FLSA’s remedial provision is a source of back pay). Because
the Portal-to-Portal Act’s remedies for overtime are found
within the FLSA, and no party disputes that the FLSA waives
sovereign immunity, the FLRA properly determined that the
United States waived sovereign immunity.4
  4
    A monetary award can be either legal or equitable in nature. See Dep’t
of Army v. Fed. Labor Relations Auth., 56 F.3d 273, 276 (D.C. Cir. 1995).
The remedy will be considered equitable if it is an attempt to give the
plaintiff what he is entitled to as opposed to a substitute for a consequen-
tial loss. See id. In Department of Army, the Army Finance and Account-
ing Office (“FAO”) increased the lag between pay periods from ten to
twelve days. See id. at 274. However, the new policy was not announced
in advance, and it resulted in several employees having insufficient funds
in their bank accounts to cover checks they had written. See id. The FLRA
ordered the FAO to reimburse all employees for monies lost or interest
charged as a result. See id. at 274-75. The D.C. Circuit noted that:
      proper notice of the pay-lag policy change was the thing to which
      the commissary employees were entitled. The interest charges for
      which the employees seek compensation are sums they lost only
      as a consequence of the Army’s failure to give them the notice
      they were due. Accordingly, any compensation for such interest
      is properly characterized as “money damages.”
Id. at 276. Ultimately, the court reviewed 5 U.S.C. § 7105(g)(3) (setting
out the powers and duties of the FLRA) and 5 U.S.C. § 7118(a)(7)
3514               DEP’T OF THE TREASURY v. FLRA
              B.    The IRS’s alternative arguments

  In its brief, the IRS makes several additional arguments,
each of which is unpersuasive.

    i.   Expressness of the CBA versus expressness of the
                           statutory

   [7] First, the IRS argues that the FLRA misconstrued the
law of sovereign immunity by basing the waiver on language
within the CBA, as opposed to the statutory text. As previ-
ously noted, only if the statutory text is explicit can the United
States’ sovereign immunity be deemed waived. See Lane, 518
U.S. at 192. The mere fact that the IRS and the NTEU came
to an agreement in the CBA regarding the compensation of
affected employees is plainly insufficient to show a waiver of
sovereign immunity. However, in this case, the FLRA did not
rely on the CBA in determining that there was a waiver of
sovereign immunity. Initially, the arbitrator found that the IRS
violated the FLSA, as amended by the Portal-to-Portal Act.
The FLRA was clear that it relied on the Portal-to-Portal Act
in determining that sovereign immunity had been waived.
Indeed, it specifically stated that 29 U.S.C. § 254(b) was “a
statute that in the circumstances presented waived the Gov-
ernment’s sovereign immunity.” Therefore, the requisite stat-
utory waiver was present, as opposed to an insufficient
contractual waiver.

(addressing prevention of unfair labor practices) of the Federal Service
Labor Management Relations Act (“FSLMRA”), and determined that the
United States had not waived sovereign immunity to the award of mone-
tary damages. Dep’t of Army, 56 F.3d at 279. However, unlike the mone-
tary award in Department of Army, the FLRA’s award of compensation in
this case was an order of the very thing to what the affected employees
were entitled to under the arbitrator’s award. Additionally, the award of
compensation in this action was under the Portal-to-Portal Act, as a com-
plement to the FLSA, as opposed to the award via the FSLMRA in
Department of Army.
                DEP’T OF THE TREASURY v. FLRA             3515
                  ii.   Air Force and NTEU

   Next, the IRS asserts that the FLRA’s order to pay compen-
sation to affected employees is in conflict with Air Force, 952
F.2d 446, and our decision in NTEU, 418 F.3d 1068. For the
following reasons, those two cases are clearly distinguishable.

   In Air Force, the Air Force petitioned for review of an
FLRA order requiring it to engage in collective bargaining
over a proposal advanced by the union. 952 F.2d at 447. The
union proposal called for overtime compensation for the time
employees were delayed in leaving the worksite due to secur-
ity measures. See id. The D.C. Circuit noted that the
FSLMRS, 5 U.S.C. §§ 7101-7135, imposed a duty on both
parties to negotiate over the conditions of employment in
good faith. See Air Force, 952 F.2d at 447 (citing 5 U.S.C.
§§ 7114, 7117). However, the court explained that the
FSLMRS stated that a federal agency may not negotiate over
proposed conditions that were inconsistent with federal law,
or a government-wide rule or regulation. See id. (citing 5
U.S.C. § 7117(a)(1)).

   Under the FSLMRS, the Office of Personnel Management
(“OPM”) is charged with the authority to issue regulations.
See id. at 448. The D.C. Circuit ultimately held that a
government-wide regulation did not allow compensation for
time spent in concluding activities that were not clearly
related to principal work activities. See id. at 453. Thus, the
court found that the union proposal was non-negotiable. In so
concluding, the D.C. Circuit expressed no opinion on whether
the regulation was in conflict with 29 U.S.C. § 254(b) of the
Portal-to-Portal Act. See id. at 452.

   Subsequent to Air Force, this Court decided NTEU. In
NTEU, we were also presented with a negotiability appeal. In
fact, in that case, the NTEU wanted to include an identical
provision to Article 29, Section 3E in its proposed new CBA
with the IRS. See 418 F.3d at 1069. The IRS approved the
3516            DEP’T OF THE TREASURY v. FLRA
provision, but the Secretary of Treasury disapproved of the
language pursuant to his duty to review the agreement under
5 U.S.C. § 7114(c). The Secretary of Treasury determined
that the provision would run contrary to 5 C.F.R.
§ 551.422(b). See NTEU, 418 F.3d at 1070. Ultimately, we
held that the provision was inconsistent with the regulation.
See id. at 1072. Thus, the provision was non-negotiable under
the FSLMRS. See id.

   Unlike both Air Force and NTEU, this is not a negotiability
appeal. Indeed, both of those cases stood for the proposition
that the federal government can — through regulation —
direct its agencies not to engage in negotiation on such issues.
See Air Force, 952 F.2d at 451 (stating that “the FSLMRS,
governs collective bargaining between federal employees and
government agencies, and § 7117 of that Act specifically bars
negotiation over proposals that are inconsistent with
government-wide regulations”). In this case, had the IRS
raised the regulations at the proper time, Air Force and NTEU
would apply. However, the mere fact that the regulations
made Article 29, Section 3E non-negotiable based on the
OPM regulations does not address the issue of whether the
Portal-to-Portal Act should be considered as part of the
FLSA’s larger statutory scheme in this case. Therefore, we
conclude that those cases are not controlling on this petition
for review.

   iii.   The Portal-to-Portal Act and Federal Employees

   [8] Next, the IRS asserts that the Portal-to-Portal Act does
not apply to federal employees. But, the Portal-to-Portal Act’s
definition of employer and employees are the same as defined
under the FLSA. See 29 U.S.C. § 262(a). When the 1974
amendments to the FLSA included federal employees, they
also amended the Portal-to-Portal Act to include federal
employees.
                DEP’T OF THE TREASURY v. FLRA             3517
  iv.   The Unfair Labor Practice decision did not lack a
                      reasoned basis

   [9] Finally, the IRS argues that the FLRA’s February 10,
2005, order lacked a reasoned basis because it was inconsis-
tent with our decision in NTEU. As previously stated, NTEU
and our holding today do not conflict. Furthermore, this argu-
ment by the IRS constitutes a collateral attack on the initial
FLRA order, which upheld the arbitrator’s award. Our review
in this case is limited to only considering whether an unfair
labor practice was committed by the IRS’s failure to imple-
ment the arbitrator’s award. See United States Marshals Serv.
v. Fed. Labor Relations Auth., 778 F.2d 1432, 1437 (9th Cir.
1985). Here, the IRS’s continuous refusal to abide by the
FLRA’s initial order enforcing the final arbitration award con-
stituted an unfair labor practice. See id.

                    IV.   CONCLUSION

   The Portal-to-Portal Act exception for compensation for
travel time must be read in conjunction with the FLSA under
these circumstances. The United States’ sovereign immunity
was waived because the FLSA expressly waives sovereign
immunity. The IRS’s petition for review is denied and the
FLRA’s petition for enforcement of its February 10, 2005,
order is granted.

 PETITION DENIED in No. 05-76031; PETITION
GRANTED in No. 05-76391; Order of the FLRA
ENFORCED.
