with whom MATTHEWS, Justice, joins dissenting in part.
I disagree with part IV of the court’s opinion, holding that DNR’s interpretation of its regulations as allowing separate ASCMCRA permits for different components of a surface coal mining operation is neither “plainly erroneous nor inconsistent with the regulations” or with ASCMCRA.
Alaska Statute 27.21.060 provides in part: “a person may not conduct a surface coal mining and reclamation operation in the state without a permit for that operation.” (Emphasis added.) See also SMCRA § 506(a), 30 U.S.C.A. § 1256(a); 11 AAC 90.002(c). The language of AS 27.21.-060 contemplates that a single permit will control all components of a “surface coal mining operation.”
The applicable definition of a “surface coal mining operation” includes the actual mine site and all facilities and structures, either off-site or on-site, that are “resulting from or incidental to” the mining. AS 27.-21.998(17). Subsection (A) defines “surface coal mining operation” in terms of “an activity” conducted at the actual mine site. AS 27.21.998(17)(A). The definition of a surface coal mining operation is further broadened in subsection (B):
(B) the areas on which an activity described in (A) of this paragraph occurs or where the activity disturbs the natural land surface, including adjacent land, the use of which is incidental to the activity; and affected by the construction of new roads or the improvement or use of existing roads to gain access to the site of the activity and for haulage; and excavation, workings, impoundments, dams, ventilation shafts, entry ways, refuse banks, dumps, stockpiles, overburden piles, spoil banks, culm banks, tailings, holes or depressions, repair areas, storage areas, processing areas, shipping areas, and other areas upon which are situated structures, facilities, or other property or materials on the surface resulting from or incidental to the activity[.]
AS 27.21.998(17).
While DNR’s assertion that “11 AAC 90.155 ... infers that a separate permit is appropriate” for the access/haul road is a plausible interpretation of that regulation, I disagree with the court’s conclusion that DNR’s interpretation is not “inconsistent with the regulations.” (Majority Op. 12) In my view, DNR’s separate permit interpretation is in direct contravention with the text of another DNR regulation, 11 AAC 90.002, which is substantially similar to AS 27.21.060(a). 11 AAC 90.002(a) provides in part “no person may conduct exploration activities or surface coal mining and reclamation operations without a permit.” (Emphasis added.)
The DNR regulations and DNR’s interpretation of those regulations and ASCMC-RA, allowing the issuance of separate permits for the access/haul road and the remainder of the mining operation, are contrary to the express purposes of ASCMC-RA. Among the enumerated purposes of the statute are “to prevent the adverse effects to society and the environment resulting from unregulated surface coal mining operations” and “to assure that surface coal mining operations are conducted in a manner that will prevent unreasonable degradation of land and water resources.” AS 27.21.010(b)(1) and (3). The court reasons that to accomplish the purposes of the Act,
at the time DNR reviews any ASCMCRA permit application it [must] consider the probable cumulative impact of all anticipated activities which will be a part of a ‘surface coal mining operation,’ whether or not the activities are part of the permit under review.
(Majority Op. 1246) I do not believe that the court’s mandated “concept approval,” in the context of an operation whose anticipated components will be covered by separate permits, is an adequate substitute for the safeguards of the single permit requirement of AS 27.21.060 in light of the goal of assuring that the agency consider *1251the cumulative or synergistic effects of a coal mining operation. In contrast to the anticipated “concept approval” approach adopted by the court, I believe that the requirement, found in AS 27.21.060, of a single permit will compel the permit applicant to plan and design the operation and its various components in more concrete and greater detail. This should lead to consideration by the permit applicant and DNR of the operation’s cumulative effect in a more careful and comprehensive manner.
Courts have disallowed segmentation of a proposed project for the purpose of preparing environmental impact statements (EISs) to assure that the cumulative effects of the project are adequately considered under the National Environmental Policy Act (NEPA). Thomas v. Peterson, 753 F.2d 754 (9th Cir.1985); see also Kleppe v. Sierra Club, 427 U.S. 390, 410-411, 96 S.Ct. 2718, 2730-2731, 49 L.Ed.2d 576 (1976); Save the Yaak Committee v. Block, 840 F.2d 714 (9th Cir.1988). In discussing a Forest Service plan to prepare an EIS for the logging access road and a separate EIS for each individual timber sale area afterward, Thomas cautioned that allowing consideration of cumulative impacts after a portion of the project is already approved “swings the balance decidedly in favor of timber sales even if such sales would have been disfavored had road and sales been considered together before the road was built.” 753 F.2d at 760. While I recognize that in some instances phased implementation of a mining operation may require a reopening and modification of the ASCMCRA permit, the same danger that Thomas counselled against inheres in the instant case. Thus, I conclude that AS 27.21.060 assures that the cumulative and synergistic effects are adequately addressed by its requirement of a single ASCMCRA permit for all components of a surface coal mining operation.