I dissent. I would affirm the Court of Appeal’s judgment.
On considering factual issues the plurality opinion imperiously concludes that:
The planning commission was wrong.
The board of supervisors was wrong.
The superior court was wrong.
The Court of Appeal was wrong.
To the contrary, it is the plurality opinion that is wrong.
The questions before us are (1) whether substantial evidence supports the superior court’s findings that Hansen Brothers Enterprises, Inc., proposed to resurrect a long-abandoned mining operation on its land and greatly intensify the exploitation of that land, and (2) whether, if the findings are supported by substantial evidence, the law requires a conditional use permit before Hansen Brothers may begin the proposed expansion. The plurality opinion’s conclusion that no permit is required rests on insufficient deference to the superior court’s factual findings.
To meet the requirements of the Surface Mining and Reclamation Act of 1975 (Pub. Resources Code, §2710 et seq.), Hansen Brothers needed to submit a reclamation plan to the board of supervisors for approval. (Id., §§ 2728, 2770.) The board rejected the plan because it ran counter to a Nevada County ordinance that provides:
“Any use lawfully in existence at the time this Chapter [i.e., the county’s zoning regulations] or amendments thereto takes effect, although such use does not conform to the provisions of this Chapter, may continue as follows:
“A. No such use shall be enlarged or intensified. Nor shall any such use be extended to occupy a greater area of land than that occupied at the time of the adoption of this Ordinance. Nor shall any such use be moved in whole or in part to any other portion of the lot or parcel of land occupied at the time of the adoption of this Chapter or amendment thereto.
“B. If the nonconforming use is discontinued for a period of one hundred eighty (180) days or more, any following use shall be in conformity with all applicable requirements of this Chapter.” (Nevada County Land Use and Development Code, art. 29, § L-II 29.2.)
The board of supervisors also informed Hansen Brothers that to pursue its plan it would need to obtain a conditional use permit. Hansen Brothers filed *578a petition for writ of administrative mandate (Code Civ. Proc., § 1094.5) and a complaint for damages and for injunctive and declaratory relief.
The superior court denied Hansen Brothers any relief. It ruled that because of the abandonment and the proposed expansion of the nonconforming use, Hansen Brothers had no right to engage in the mining it proposed. Specifically, it found, with regard to abandonment, that “the [hillside] operation has been largely inactive since 1986 except for storage of aggregate and one or two trips per year by trucks to or from the site. The area previously used as a rock quarry is overgrown with trees 15 feet tall. All of these factors cause[] the Court to conclude the hillside quarry operations were separate operations that had been discontinued for the statutory period.” With regard to enlargement, it found that “[m]ining with a total production of 5,000,000 cubic yards of material, as reflected in the proposed reclamation plan, is a substantial change and expansion and intensification[,] as illustrated by the fact such proposed use would involve 120 [10-cubic-yard] truck trips per day as contrasted to the one or two per year shown by the evidence since 1986.”
“Where a superior court is required to make ... an independent judgment upon the record of an administrative proceeding, the scope of review on appeal is limited. An appellate court must sustain the superior court’s findings if substantial evidence supports them. [Citations.] In reviewing the evidence, an appellate court must resolve all conflicts in favor of the party prevailing in the superior court and must give that party the benefit of every reasonable inference in support of the judgment. When more than one inference can be reasonably deduced from the facts, the appellate court cannot substitute its deductions for those of the superior court.” (Pasadena Unified Sch. Dist. v. Commission on Professional Competence (1977) 20 Cal.3d 309, 314 [142 Cal.Rptr. 439, 572 P.2d 53].) The superior court was required to make an independent judgment on the administrative record here. (Halaco Engineering Co. v. South Central Coast Regional Com. (1986) 42 Cal.3d 52, 64, fn. 10 [227 Cal.Rptr. 667, 720 P.2d 15].)
Whether the standard set forth in Pasadena Unified Sch. Dist. v. Commission on Professional Competence, supra, 20 Cal.3d 309, 314, applies in every instance we need not decide. It is clear that it applies in this case. A ruling that a nonconforming use was intensified or abandoned involves a question of fact that we review on a deferential standard. (See McCaslin v. City of Monterey Park (1958) 163 Cal.App.2d 339, 348 [329 P.2d 522]; cf. Texas Nat. Theatres v. City of Albuquerque (1982) 97 N.M. 282, 288 [639 P.2d 569, 575] [applying New Mexico substantial evidence standard].)
Before turning to the question whether substantial evidence supports the superior court’s findings of abandonment and intensification, we must review the law applicable to those matters.
*579Because a nonconforming use “endangers the benefits to be derived from a comprehensive zoning plan” (City of Los Angeles v. Gage (1954) 127 Cal.App.2d 442, 459 [274 P.2d 34]), the law aims to eventually eliminate it (City of Los Angeles v. Wolfe (1971) 6 Cal.3d 326, 337 [99 Cal.Rptr. 21, 491 P.2d 813]). However, to avoid constitutional problems an existing nonconforming use will be tolerated as long as it does not expand to a significant extent. (Edmonds v. County of Los Angeles (1953) 40 Cal.2d 642, 651 [255 P.2d 772]; Sabek, Inc. v. County of Sonoma (1987) 190 Cal.App.3d 163, 166-167 [235 Cal.Rptr. 350].) “ ‘The underlying spirit of a comprehensive zoning plan necessarily implies the restriction, rather than the extension, of a nonconforming use of land, and therefore ... a condition that the lawful nonconforming use of land existing at the time of the adoption of the ordinance may continue must be held to contemplate only a continuation of substantially the same use which existed at the time of the adoption of the ordinance, and not some other and different kind of nonconforming use which the owner of the land might subsequently find to be profitable or advantageous. . . .’” (County of Orange v. Goldring (1953) 121 Cal.App.2d 442, 447 [263 P.2d 321], quoting In re Botz (1942) 236 Mo.App. 566 [159 S.W.2d 367, 372].) Moreover, the use must be continuous: if abandoned, it may not be resumed. “ ‘ “A nonconforming use is a lawful use existing on the effective date of the zoning restriction and continuing since that time in nonconformance to the ordinance.” . . . .’ [Citations.] Nonuse is not a nonconforming use. . . . This rule is consistent with the further rule that reuse may be prohibited when a nonconforming use is voluntarily abandoned.” (Hill v. City of Manhattan Beach (1971) 6 Cal.3d 279, 285-286 [98 Cal.Rptr. 785, 491 P.2d 369].)
Substantial evidence supports the superior court’s findings of abandonment and proposed intensification.
As regards abandonment: a neighbor of Hansen Brothers presented to the board of supervisors a series of photographs and testified that the hillside has “trees of 10 to 15 years growing over” them. The photographs evidently became the center of the board’s attention as other neighbors discussed them. One said that the photographs showed that the hillside excavations were “just primarily top soil” and that the presence of tall trees made it “quite obvious that none of that quarrying operation has gone on for many years.” The foregoing evidence caused one member of the board to state, “I was much impressed by the photographs that we had of the sites which had been once upon a time quarried. And upon those sites we have 25- and 30-foot trees indicating that certainly for a good number of years that site has been undisturbed . . . . [^Q The documentation I have before me shows me that those areas haven’t been mined in years and years and years.”
*580Yet another neighbor sent a handwritten letter to the board of supervisors, stating in part: “We have a home in the community where the Hansen Brothers are wanting to start a new mining operation alongside the Bear River, Our house is on a hill overlooking the river and the beautiful wooded hills around it. During the 3Vi years we have lived here, the Hansen’s [szc] gravel operation has been inactive. . . . We have never seen any Hansen trucks on the road or any mining activity at the site. We have observed only a couple [of] piles of gravel which have stayed there untouched. . . .”
Indeed, there was testimony that more than 20 neighboring property owners signed a petition against Hansen Brothers’ plan, declaring in part that, “we can personally attest to the lack of activity at the gravel quarry over the last few years.”
As regards intensification: recall that there was evidence that previous excavations consisted of cuts in the topsoil. Under the reclamation plan, Hansen Brothers would begin a drill-and-blast operation that would carve out 500,000 cubic yards of overburden—approximately the volume of 200,000 standard-sized pickup truck beds—and would excavate and remove from the site an average of 50,000 cubic yards of material—a rough equivalent to the volume of 20,000 pickup-truck beds—every year for the next century.
As one witness, a registered civil engineer and lawyer with 40 years’ experience in mining, told the planning commission, “they’re talking about making a cut there with vertical rock faces at about 20-foot intervals benched of [sz'c] about 300 feet high. . . . And it’s about a half a mile long. And you don’t get rock to stand at those angles without it being of a quality that it has to be drilled and blasted.” The previously quoted handwritten letter stated: “The mining operation the Hansenfs] are proposing would be a total change from the operation we have observed over the past 3V2 years. They have never touched the hills or land rock. A commencement of such activity would be a great disruption of the tranquility and beauty of the stable community which has built up in this area—an area which is zoned for light farming .... It would be an activity completely incompatible with the single-family parcels and open spaces currently in this community.”
In sum, the record contains substantial evidence to support the superior court’s findings of abandonment and proposed intensified use.1
Fairly examined, the record reveals that Hansen Brothers proposes to move its nonconforming mining operation from a riverbed and a riverbank to *581nearly pristine hillsides, where its new mine will create a moonscape. It is, as the superior court found, a proposed “separate operation^ . . . .” And this destruction will occur without so much as the requirement of a permit.2
I cannot agree with this doleful outcome, which will occur in violation of settled legal principles. I therefore dissent.
It is true that no evidence supports the superior court’s conclusion that there would be 120 large-truck trips per day under the proposed plan. The court relied on testimony that *581overstated the number of trips by an order of magnitude. Nevertheless, 12 trips a day (a figure supported by substantial evidence) by large trucks over what testimony revealed to be narrow and winding roads is a great increase from virtually no truck movement at all.
The plurality opinion leaves open the question whether intensification of Hansen Brothers’ nonconforming use will eventually violate the zoning ordinance. The superior court’s findings already establish, however, that it will. In any event, the practical problem with the plurality opinion’s holding is that, by the time the evidence of intensification becomes apparent and a remedy is sought and obtained, serious damage may well already have been inflicted.