The Bureau of Taxation appeals from a judgment of the Superior Court, Kennebec County, affirming a decision of the State Board of Property Tax Review that lowered the state valuation of the Town of Madison from that set by the bureau. Because we agree with the bureau’s argument that the board exceeded its statutory authority, we vacate the judgment.
The statutes involved in this appeal are contained in 36 M.R.S.A. §§ 201-458 (1978 & Supp.1987). Section 208 (Supp.1987) imposes on the bureau the duty of equalizing and adjusting the assessment lists of each municipality. When any municipality is aggrieved by the bureau’s determination, that municipality may appeal to the board pursuant to section 272. In proceedings before the board the bureau has the burden of showing that its determination is reasonable and the municipality’s claims are unreasonable. Id. § 272(3) (Supp.1987).
Madison’s appeal to the board to review the bureau’s assessment involved little, if any, factual dispute. For purposes of judicial review, we examine only the disagreement between the parties over the valuation of a hydroelectric facility owned by Madison Paper Industries. The facility is located on the town line between Madison and Anson, along the Kennebec River. The bureau assigned an equalized value of approximately $9.5 million to that portion of the plant located in Madison.1 The town conceded and the board agreed that the bureau’s valuation represented the fair market or just value of the Madison facili*940ty. At the same time, two other hydroelectric facilities of similar size, age, and function located in adjacent municipalities were assessed at a substantially lower value by the bureau. Unlike the Madison facility, these other facilities are owned by Central Maine Power Company, and thus subject to regulation by the Maine Public Utilities Commission. The board concluded that the bureau had failed to justify this disparate treatment of similar facilities.
The record established that the bureau used one method of valuation for the facility in Madison, and a different method for the regulated facilities. As a result, the bureau’s valuation of the Madison facility was substantially greater than its valuation of the regulated facilities located nearby. The parties disagree as to whether the fact of PUC regulation alone justifies the difference in the bureau’s method of assessing the facilities. Because the board lacked the authority in this proceeding to raise the state valuation of those other towns, it elected instead to lower Madison’s state valuation by $5.27 million. On the bureau’s complaint for judicial review of the board’s decision, the Superior Court affirmed the board. On appeal before us, the bureau argues that its disparate treatment of hydroelectric facilities is justified because PUC regulation substantially affects market value of the CMP-owned plants. The bureau argues further that the board acted beyond its statutory authority.
We conclude that the board misconceived its role in the tax equalization process and that it lacked any statutory authority to remedy a perceived inequality in the manner attempted. We thus need not address the question whether the bureau’s disparate treatment was justified. For purposes of this opinion, we are concerned with the method of tax equalization applicable to municipalities. We use the term “state valuation” to mean “the equalized just value of all real and personal property in each municipality” that the Bureau of Taxation must certify to the Secretary of State pursuant to 36 M.R.S.A. § 305(1) (1978 & Supp.1987). That state valuation is utilized both to apportion county taxes among the municipalities and to calculate each municipality’s share of various state-funded programs and it must “be based on 100% of the current market value.” Id.
Municipal assessors are required to transmit to the bureau a list of property assessed in their respective municipalities. 36 M.R.S.A. §§ 381-383 (1978 & Supp. 1987). The bureau must “equalize and adjust the assessment list of each town, by adding to or deducting from it such amount as will make it equal to its just value.” Id. § 208 (Supp.1987). The “equalized just value shall be uniformly assessed in each municipality ... and shall be based on 100% of the current market value.” Id. § 305. Thereafter, notice of the proposed valuation is sent to each municipality. Id. § 208. Any municipality aggrieved by the bureau’s determination may appeal to the State Board of Property Tax Review. Id. § 272(1). After hearing, the board has the power to “raise, lower or sustain” the state valuation “with respect to the municipality which has filed the appeal.” Id. § 272(4)(A) (emphasis added). “If the board does not sustain the bureau’s determination, it shall make its own reasonable determination giving due weight to the claims of the municipality and the Bureau of Taxation.” Id. § 272(3).
We conclude that once the board had determined the validity of the bureau’s assessment of the Madison facility at current market value, it was compelled to sustain the bureau’s determination. The town conceded and the board found that the bureau had assessed the Madison facility at its fair market value or just value. The board’s power to lower the bureau’s valuation of the Madison facility was implicitly limited by the statutory mandate requiring that the assessment be based on market value. 36 M.R.S.A. § 305 (Supp.1987). Madison’s claim that the facility be assessed differently to compensate for the bureau’s disparate treatment of regulated facilities located in other municipalities must be addressed in a different forum. Neither the bureau, in assessing the Madison facility, nor the board, in fashioning a remedy, has the authority to deviate from fair market or just value.
*941The town relies on Kittery Electric Light Co. v. Assessor of the Town of Kittery, 219 A.2d 728 (Me.1966) for the assertion that where an assessment does not satisfy the constitutional and statutory goals of uniformity and just value, uniformity should take precedence. Id. at 733-34. Thus, the town argues, because. the regulated facilities were not assessed at just value, the board’s remedy of lowering Madison’s assessment was proper because it achieved uniformity by bringing the valuation of the Madison facility in line with that of the regulated facilities. See Farrelly v. Town of Deer Isle, 407 A.2d 302, 307 (Me.1979).
We are not concerned with varying assessment practices within a single municipality. Rather, Madison has attacked the bureau’s assessment of regulated hydroelectric facilities located outside the town. Clearly, the board has no authority to alter the bureau’s assessment of municipalities not before it. The statute explicitly provides the board with the power to adjust the state valuation only “with respect to the municipality which has filed the appeal,” in this case, the Town of Madison. 36 M.R.S.A. §§ 272(4)(A).
In sum, we do not decide the question whether the bureau improperly undervalued the hydroelectric facilities that are subject to PUC regulation. Rather, we hold that the board exceeded its statutory authority in attempting to correct the perceived inequality in valuation of the facilities by lowering the valuation of the Madison facility below the board's determination of market value. Accordingly, the judgment of the Superior Court must be vacated and the case remanded with direction that the Superior Court order the board to “sustain the state valuation as determined by the bureau.”
The entry is:
Judgment vacated.
Remanded to the Superior Court for entry of judgment directing the State Board of Property Tax Review to sustain the state valuation of the Town of Madison.
McKUSICK, C.J., and NICHOLS, WATHEN and SCOLNIK, JJ., concur.
. For our purposes the $9.5 million represents the same value as that assessed by the Town of Madison and is included in the $212.5 million that represents the total state valuation of the town of 1987.