Performance Friction Corporation (“the Company”) petitions for review of a Decision and Order entered against it by the National Labor Relations Board (“the Board”). On April 22, 2003, the Board Ordered that the Company pay employees Jerry Kennedy (“Kennedy”) and Manuel Mantecón (“Mantecón”) backpay with interest. * The Board cross-applies for enforcement of its Order, and we have granted United Automobile, Aerospace & Agricultural Implement Workers of America (“the Union”) leave to intervene. Reviewing this case for an abuse of discretion, we defer to the findings of the Board and hold that the Board properly calculated and awarded backpay with interest. As explained below, we deny the Petitions for Review and grant the Cross-Applications for enforcement.

I.

On June 30, 1997, we affirmed the Board’s findings that the Company had violated sections 8(a)(1) and (3) of the National Labor Relations Act (“NLRA”). 29 U.S.C. §§ 158(a)(1), (3). We then remanded the case to the Board for a recalculation of backpay. Performance Friction v. NLRB, 117 F.3d 763, 766 (1997). On November 24, 1998, the Board’s Regional Director received evidence and heard argument before ordering the Company to provide backpay to both Kennedy and Mantecón, along with four others. The Board calculated the amount of back-pay utilizing a “comparable or representative employee” formula based on an average of eighteen employees who worked throughout the entire backpay period in comparable positions to Mantecón and Kennedy.

The Company now petitions for review of the decision challenging the Board’s award of backpay on three fronts. First, the Company argues that “Kennedy and Mantecon’s mendacious behaviors were a fraud on and a flagrant abuse of Board processes and therefore completely bar any backpay.” Next, the Company argues that the Board improperly awarded back-pay without requiring Kennedy to prove that he mitigated his damages. Lastly, the Company contends that the calculation method was improper.

II.

The disposition of this case turns solely on the application of the standard of review, which is settled law in this Circuit. The NLRA mandates that the Board’s factual findings “shall be conclusive” so long as “supported by substantial evidence on the record.” 29 U.S.C. § 160(e); Sam’s Club v. NLRB, 173 F.3d 233, 239 (4th Cir. 1999). Credibility determinations are given deference absent exceptional circumstances and are reviewed solely for an abuse of discretion. Sure-Tan, Inc. v. NLRB, 467 U.S. 883, 898-99, 104 S.Ct. 2803, 81 L.Ed.2d 732 (1984). The Board’s interpretation of the NLRA is deferred to so long as “reasonably defensible,” WXGI, Inc. v. NLRB, 243 F.3d 833, 840 (4th Cir. 2001), and the Board’s application of the law to the facts is reviewed solely to determine whether it is “supported by substantial evidence based upon the record as a whole.” Sam’s Club, 173 F.3d at 239. *724 Further, the Board’s ordered remedy is reviewed for an abuse of discretion and will only be disturbed in the extraordinary circumstance where it is “arbitrary, capricious, or manifestly contrary to the [NLRA].” Coronet Foods v. NLRB, 158 F.3d 782, 788 (4th Cir. 1998) (internal quotations omitted); ABF Freight Sys. v. NLRB, 510 U.S. 317, 324, 114 S.Ct. 835, 127 L.Ed.2d 152 (1994); Aneco Inc. v. NLRB, 285 F.3d 326, 329 (4th Cir. 2002).

III.

In this Court’s view, the Board’s findings are supported by substantial evidence on the record, and there are no exceptional circumstances that warrant a finding that the Board abused its discretion. Consequently, we affirm the findings and conclusions of the Board. First, with respect to Mantecon’s and Kennedy’s behavior, while “[f]alse testimony in a formal proceeding is intolerable,” ABF Freight Sys., 510 U.S. at 323, the Board explicitly found that “Mantecón did not make any intentional misleading statements.” J.A. 526 n. 11. Here, there was neither exceptional circumstances, nor an abuse of discretion. Consequently, we defer to the Board’s credibility determination. However, with respect to Kennedy, the Company argues that he purposely lied about his incarceration and efforts to mitigate, and should therefore be denied backpay. In American Navigation Co. v. Adams, the Board held that “discriminatees found to have willfully concealed from the Board their interim employment will be denied backpay for all quarters in which they engaged in the employment so concealed.” 1983 WL 24760, 268 N.L.R.B. 426, 427 (1983). Therefore, the Board appropriately withheld payment for the quarters corresponding to the term of Kennedy’s incarceration.

Second, we conclude that any omission in the Board’s Order with respect to Kennedy’s mitigation efforts are attributable to the Company’s failure to meet its burden of proof. While “employees who lose their jobs as a result of an unfair labor practice must mitigate their damages by making a ‘reasonable effort to obtain interim employment,”’ Aneco Inc., 285 F.3d at 330 (4th Cir. 2002) (quoting Coronet Foods, 158 F.3d at 800), the burden rests upon “the employer who committed an unfair labor practice to establish facts that reduce the amount due for gross backpay.” Minette Mills, Inc., 1995 WL 149236, 316 N.L.R.B. 1009,1010 (1995). The Company offered no evidence to justify a reduction in the amount of backpay awarded to Kennedy. The Company failed to meet its burden and, therefore, the Board did not abuse its discretion in awarding backpay to Kennedy.

Third, backpay was calculated utilizing a comparable or representative employee formula based on an average of eighteen employees who worked throughout the entire backpay period in comparable positions to Mantecón and Kennedy. The Board’s calculation method was objectively reasonable based on substantial evidence and is entitled to deference. There has been no abuse of discretion. See Coronet Foods, 158 F.3d at 800 (quoting Bagel Bakers Council v. NLRB, 555 F.2d 304, 305 (2d Cir. 1977) (finding that the Board’s decision to “proceed by one method rather than another hardly makes out a case of abuse of discretion”)).

IV.

For the foregoing reasons, Performance Friction Corporation’s Petition for Review is denied; the Board’s Cross-Application for Enforcement of its Decision and Order of April 22, 2003, is granted; the Intervenor Union’s Petition for Review as to *725 Mantecón is denied, and the Intervenor Union’s Application for Enforcement of the Board’s decision as to Kennedy is granted.

PETITION FOR REVIEW IS DENIED; CROSS-APPLICATION FOR ENFORCEMENT IS GRANTED; INTERVENOR’S PETITION FOR REVIEW IS DENIED; AND INTERVENOR’S APPLICATION FOR ENFORCEMENT IS GRANTED