HENDERSON, Justice.
PROCEDURAL HISTORY/ISSUES
This is a voluminous compilation of appeals and notices of review originally emanating from South Dakota Game, Fish and Parks Commission’s (Defendants) decision to not renew cabin site lease permits held by cabin owners (Plaintiffs) in Custer State Park. There are approximately 4,000 pages of record, exhibits and testimony, plus over 300 pages of briefs and accompanying appendices. Following our remand in Moulton v. State, 363 N.W.2d 405 (S.D.1985) (Moulton I), the circuit court decided various legal questions presented to it. The following issues are presently before this Court on appeal.
(1) # 15373 — Plaintiffs appeal lease non-renewal policy asserting theories of
(a) estoppel regarding alleged ninety-nine-year leases
(b) constitutional law
1. substantive due process
2. equal protection
3. procedural due process
4. 42 U.S.C. § 1983
(c) environmental protection
(2) # 15382 — Defendants appeal circuit court’s dismissal of Plaintiffs’ administrative appeal addressing termination of cabin permits
[489]*489# 15384 — Plaintiffs file notice of review
(3) #15374 — Plaintiffs appeal circuit court’s dismissal of their appeal from Commission’s 1984 decision to raise cabin site rentals
# 15379 — Defendants file notice of review
These issues are treated seriately. Respectively, we reverse and remand for trial, reverse and remand with instructions, and reverse.
PACTS
We refer to the facts in our prior opinion, Moulton I, 363 N.W.2d 405. Recapitulating, Custer State Park Board was created in 1919, and authorized, legislatively, to purchase lands designated as Custer State Park. Custer State Park Board was abolished and replaced by the South Dakota Park Board in 1939 which itself was, in 1945, transformed into the Department of Game, Fish and Parks.
Beginning in 1921, erection of cottages within Custer was encouraged. Structures built were owned by individuals while the land upon which cabins rested remained state property. It appears that some original cabin owners may have been offered ninety-nine-year leases by Park officials and this is indicated by affidavits, a deposition, and in two instances by written lease agreement. A former Park official, E.L. Burns, who served from 1937 non-inclusively to 1946, noted that cabin site leases during those periods did not contain a fixed term of years and only detailed the amount of the annual lease payment. This former official further stated that the general feeling toward cabin owners was that if they maintained their cabins and broke no park rules, their cabins would not be disturbed. Subsequent leases (dating from approximately 1949) contained terms of ten or five years.
In 1966, the legislature amended the South Dakota Code to repeal that section containing an expressed legislative policy of encouraging private cabin sites in Custer State Park. At a meeting held in December 1967, the Game, Fish and Parks Commission (Commission) decided to terminate private cabin site leases in Custer State Park effective December 31, 1982. Cabin site lessees were not given advance notice of this meeting, but were apprised of Commission’s decision to discontinue cabin leases. All lease permits issued in 1978 contained a provision that they would not be renewed beyond December 31,1982. Some cabin owners objected to the nonrenewable leases but they later relented upon learning that the alternative to not signing was a failure to renew for any period at all.
In 1978, cabin owners organized an unincorporated association designed to explore alternatives to removing cabins from Custer State Park. A lawsuit was filed in 1980 challenging Commission’s December 1967 decision. In 1981, the parties entered into a stipulation for dismissal of this lawsuit, which provided that Commission’s 1967 decision to terminate cabin site leases was only a statement of policy, not binding on the present Commission. Commission met on June 4 and 5, 1982 to again consider cabin site leases within Custer State Park. On June 5, 1982, Commission unanimously voted to allow all leases to terminate December 31, 1982.
On June 15, 1982, some cabin owners filed a Notice of Appeal to Commission’s decision. This action triggered events which led to this Court’s decision in Moul-ton I. Encapsulating, in Moulton I, we held inter alia:
(1) The abandonment of legislative policy “encouraging” private cabin sites meant that cabin leases may be terminated at Commission’s discretion; and
(2) Subsequent lease agreements for a term of years signed by one Kenneth Harrod supersede prior lease agreements, and oral representations must yield to written contracts.
While we were deciding Moulton I, Commission, in 1984, increased annual cabin site rents from $35 to $375-$500. Upon remand, the circuit court ruled as follows:
(1) Granted State’s Motion for Summary Judgment holding that Commission’s decision to discontinue lease renewal [490]*490policy was valid, and estoppel, constitutional, and environmental protection claims raised by cabin owners were unpersuasive. Plaintiffs appeal.
(2) Dismissed Plaintiffs’ administrative appeal (without prejudice) concerning Commission’s June 1982 decision not to renew cabin site leases. Defendants appeal. Plaintiffs file notice of review.
(3) Dismissed Plaintiffs’ administrative appeal regarding the 1984 rent increase on the theory that contested case procedure was not applicable. Plaintiffs appeal. Defendants file notice of review.
These appeals and notices of review were consolidated for presentation before this Court.
DECISION
I.
ESTOPPEL
Plaintiffs contend the circuit court erroneously granted Defendants’ Motion for Summary Judgment. They urge, based upon the settled record, that Defendants should be estopped from denying the validity of the ninety-nine-year leases or, in the alternative, that we reverse and remand because genuine issues of material fact exist as to whether estoppel may be asserted in this situation. Defendants counter that (a) there exists no substantial evidence of record that such leases existed or that promises of leases were made; (b) no estop-pel of a state government entity is possible under South Dakota law; and (c) our prior holding in Moulton v. State, 363 N.W.2d 405, 408-09 (S.D.1985), strongly implies preclusion of Plaintiffs’ estoppel claim. We are convinced that genuine issues of material fact exist and we reverse and remand for trial.
a. Whether ninety-nine-year leases were offered to Plaintiffs is a genuine issue of material fact.
As to the existence of ninety-nine-year leases or promises of same, the record is sketchy. Filed, are five affidavits and one deposition from Plaintiffs all stating that promises of ninety-nine-year leases were made.1 Additionally, attached to Kenneth Harrod’s affidavit is a “Term Occupancy Permit” dated June 24, 1939, issued by Custer State Park Board, which gives to Rose M. Hutchins Briggs (a Harrod predecessor) permission to use cabin site land “for a period of 99 years from date hereof[.]” Another “Term Occupancy Permit” in identical form to the one above, was issued to the School and Public Land Department; a lease term of ninety-nine years is specified. In years prior to 1949, in most instances, no specific term of years appears on the “Term Occupancy Permit”;2 rather, that space was left blank. An affidavit by E.L. Burns, an Assistant Superintendent and later Superintendent of Custer State Park non-inclusively from 1937 to 1946, recites that “the general feeling toward the cabin owners ... was that as long as [they] maintained their cabin sites in a satisfactory condition and did not violate any park [491]*491rules or regulations, the cabins would not be bothered.” Therefore, we do not agree with Defendants that the record is devoid of evidence supporting ninety-nine-year leases.
Defendants alternately claim that any evidence existing is rendered useless by virtue of its hearsay status. This assertion is erroneous. “Term Occupancy Permits” issued by Custer State Park Board to both Harrod predecessor Rose M. Hutchins Briggs and to the School and Public Land Department specify that ninety-nine-year leases were offered and accepted. These leases are clearly statements offered against a declarant party (affidavits of Sweem, Kuppinger, Ward, and Craft arguably also contain statements against interest, see n. 1 and accompanying text, supra), which has been expressly designated as “not hearsay” by the legislature. SDCL 19-16-3. See United States v. Moskowitz, 581 F.2d 14 (2d Cir.1978). We are also mindful of former Park Superintendent Burns’ affidavit (although offered by Defendants) which implies that park officials in the 1930’s and 1940’s anticipated an extremely long-term cabin presence within Custer State Park. Lastly, we realize that absent long-term leases, the possibility exists that cabins would not have been built.
b. Estoppel of a state government entity is possible under South Dakota law.
An estoppel may arise when
[a] promise which the promisor should reasonably expect to induce action or forbearance on the part of the promisee or a third person and which does induce such action or forbearance is binding if injustice can be avoided only by enforcement of the promise. The remedy granted for breach may be limited as justice requires.
Restatement (Second) of Contracts § 90(1) (1981). Initially, we should observe that “ ‘estoppels against the public are little favored and should be used sparingly.’ ” Sioux Valley Hosp. Ass’n v. Tripp County, 404 N.W.2d 519, 522 (S.D.1987) (quoting City of Rapid City v. Hoogterp, 85 S.D. 176, 179, 179 N.W.2d 15, 17 (1970)). See Sioux Falls Constr. Co. v. City of Sioux Falls, 297 N.W.2d 454 (S.D.1980); Northwestern Pub. Serv. Co. v. City of Aberdeen, 90 S.D. 627, 244 N.W.2d 544 (1976); Rhodes v. City of Aberdeen, 74 S.D. 179, 50 N.W.2d 215 (1951); Griffis v. State, 69 S.D. 439, 11 N.W.2d 138 (1943). “ ‘[M]ere ... acquiescence is not sufficient to permit an estoppel. Some affirmative action must have been taken upon which the other party acted in reliance and substantially changed his position.’ ” Sioux Valley Hosp. Ass’n, 404 N.W.2d at 522 (emphasis added) (quoting Northwestern Pub. Serv. Co., 90 S.D. at 637, 244 N.W.2d at 549). See Hoogterp, 85 S.D. at 179-80, 179 N.W.2d at 16-17; Missouri River Tel. Co. v. City of Mitchell, 22 S.D. 191, 199, 116 N.W. 67, 70 (1908). Also, “[t]he burden of proving the elements of affirmative action, reliance and change of position is upon the party contending the legal right is waived.” Northwestern Pub. Serv. Co., 90 S.D. at 637, 244 N.W.2d at 549 (citing Aune v. City of Mandan, 167 N.W.2d 754 (N.D.1969)). See Sioux Falls Constr. Co., 297 N.W.2d at 459 (quoting Hoogterp, 85 S.D. at 180, 179 N.W.2d at 17).
However, this Court has observed that estoppels may be applied against the public “ ‘when exceptional circumstances demand their application to prevent manifest injustice.’ ” Sioux Valley Hosp. Ass’n, 404 N.W.2d at 522 (quoting Hoogterp, 85 S.D. at 180, 179 N.W.2d at 17). See Heckler v. Community Health Servs., 467 U.S. 51, 104 S.Ct. 2218, 81 L.Ed.2d 42 (1984); Tosco Corp. v. Hodel, 611 F.Supp. 1130 (D.C.Colo.1985); 28 Am.Jur.2d Estoppel and Waiver § 123 (1966); 31 C.J.S. Estoppel § 140 (1964). Furthermore, “no branch [of government] is entirely immune from scrutiny. The courts must weigh the degree of manifest injustice against the effect, in the particular case, of intervention into the public processes.... There is no rule of thumb.” Eden v. Board of Trustees of State Univ., 49 A.D.2d 277, 284, 374 N.Y.S.2d 686, 692 (1975).
We also remain mindful that estoppel was successfully applied against a state governmental entity in Northern Improve[492]*492ment Co. v. South Dakota State Highway Comm’n, 267 N.W.2d 208 (S.D.1978). See also Missouri River Tel. Co., 22 S.D. at 199-200, 116 N.W. at 70. In Northern Improvement, we held that South Dakota State Highway Commission (Defendant) was estopped from claiming that a written order was a necessary precursor to an enforceable modification of the contract existing between Northern Improvement Company, a highway construction contractor (Plaintiff) and Defendant, when Plaintiff had numerous discussions with Defendant’s engineers, concerning additional work and pay, and when those engineers were given broad discretionary powers by the contract. In distinguishing this case from others in which estoppel arguments failed, we pointed out that Defendant’s engineer was granted broad discretionary powers; i.e., Defendant’s engineer was acting within the scope of his authority. See Northern Improvement, 267 N.W.2d at 214.
Defendants attempt to distinguish Northern Improvement from our present case in three ways. First, Defendant’s engineer in Northern was vested, contractually, with great discretionary power and Custer State Park Board members were not. Second, Northern was a situation where a public improvement (highway) was being constructed involving interplay between State’s engineers and highway contractors, a relationship which approximates contracting between private parties, whereas the Commission’s decision regarding parklands is a discretionary one involving execution of public policy. Third, in Northern, there was no subsequent written contract and in the present case, nonrenewable lease permits were offered to, and signed by, all cabin owners.
Defendants’ argument is unpersuasive. First of all, there is sufficient evidence in the record to raise a question of fact concerning whether ninety-nine-year leases were offered to cabin owners.3 These offers could constitute compliance with the affirmative act requirement discussed earlier. See Sioux Valley Hosp. Ass’n, 404 N.W.2d at 522; Sioux Falls Constr. Co., 297 N.W.2d at 459; Northwestern Pub. Serv. Co., 90 S.D. at 637, 244 N.W.2d at 549. If the fact finder believes Plaintiffs’ version of the facts, it may adopt the position, that the Board, in toto approved of the ninety-nine-year leases offered by various Park personnel.4 We believe the evidence is sufficient to raise a genuine issue of material fact as to whether Board authorized the offering of ninety-nine-year leases inducing Plaintiffs’ reliance and resulting in a change of position which culminated in cabin erection. See Sioux Valley Hosp. Ass’n, 404 N.W.2d at 522; Sioux Falls Constr. Co., 297 N.W.2d at 459; Northwestern Pub. Serv. Co., 90 S.D. at 637, 244 N.W.2d at 549; Hoogterp, 85 S.D. at 179-80, 179 N.W.2d at 16-17. In any event, the settled law of South Dakota permits estoppels to be applied against the public if the facts warrant such a result.
c. Our holding in Moulton I does not preclude Plaintiffs’ estoppel claim.
Defendants point out that 1978 cabin site permits, issued by Commission, contained a clause notifying Plaintiffs that all permits terminated on December 31, 1982 and were nonrenewable, and this Court, in Moulton I, 363 N.W.2d at 408, essentially wrote that any prior ninety-nine-year leases must yield to subsequent written contracts. Defendants conclude that our own language in Moulton I is dispositive of the current controversy. We do not agree.
In Moulton I, we specifically declined to address Plaintiffs’ estoppel and constitutional law claims as “[t]hese arguments were addressed only in the trial court’s [493]*493memorandum decision, which is not reviewable on appeal.” Moulton I, 363 N.W.2d at 409 (numerous citations omitted). Unquestionably, Plaintiffs’ estoppel and constitutional law claims are now properly before this Court and we refuse to apply the confines and words of Moulton I to the present case in which estoppel is properly raised and may be fully considered. We also note the record, which contains affidavits and evidence, alleging that Plaintiffs were forced to sign the 1978 nonrenewable agreements or forfeit all cabin site rights. Plaintiffs’ estoppel argument bolsters the assertion that this was nothing more than Defendants’ unilateral modification of existing lease agreements to which Plaintiffs agreed because no other viable choice was offered.
Therefore, the circuit court erred in granting Defendants’ Motion for Summary Judgment concerning the estoppel issue. We hold that genuine issues of material fact exist as to (1) the existence of ninety-nine-year leases; (2) the present effect, if any, of those leases; (3) the impact, if any, of Plaintiffs’ signing of 1978 nonrenewable agreements on prior lease agreements; and (4) the right of succession of present cabin owners. We reverse and remand for resolution of these factual inquiries.
II. AND III.
CONSTITUTIONAL AND ENVIRONMENTAL CLAIMS
Plaintiffs advocate that Defendants’ termination of cabin site leases resulted in the following constitutional violations.
1. Substantive Due Process
2. Procedural Due Process
3. Equal Protection
4. 42 U.S.C. § 1983.
They also assert that the decision to terminate cabin site leases will be injurious to the environment in that removal of cabins will cause permanent damage.
We view resolution of the estoppel issue and its related inquiries a necessary prerequisite to any review of these claims. If Plaintiffs are successful in proving their estoppel cause of action, environmental and constitutional claims may be rendered moot. Also, because termination of cabin site permits was never previously considered by this Court from a constitutional posture, we observe that there is a difference between an initial grant of a permit and the termination of a permit once granted. Due process requirements accompanying each situation vary and may be further affected by the factual findings entered at the circuit court level. As these claims are not judicially ripe, we therefore decline to specifically address them5 and leave their resolution, if necessary, to the circuit court upon remand.
IV.
ADMINISTRATIVE APPEALS
First Administrative Claim.
Appeal was taken to the circuit court addressing Commission’s June 1982 decision to terminate cabin site leases in Custer State Park. The circuit court found that Commission had not entered findings of fact and conclusions of law as mandated by SDCL 1-26-25. Moreover, pursuant to SDCL 1-26-30.1, the circuit court decided that Plaintiffs should have filed a proposed [494]*494decision including findings of fact and conclusions of law with Commission. Since this filing was not accomplished, Plaintiffs’ administrative appeal was dismissed without prejudice. Defendants appealed advocating that the dismissal should have been with prejudice. Plaintiffs filed notice of review contending Commission’s decision to terminate cabin site leases was a contested case, and the circuit court erred when it did not remand the 1982 administrative appeal to Commission and require it to make findings of fact and conclusions of law. We agree with Plaintiffs and reverse the circuit court’s decision and remand to the court with instructions.
The crux of Plaintiffs’ argument is that Commission must comply with contested case procedures of the Administrative Procedure Act. The key to identifying a contested case is whether “rights, duties, or privileges of a party are required by law to be determined by an agency after an opportunity for hearing....” SDCL 1-26-1(2) (iquoted in Carlson v. Hudson, 277 N.W.2d 715, 717-18 (S.D.1979)). There are three methods by which a hearing may be “required by law”: (1) statute; (2) agency rule; or (3) due process constitutional mandate. Carlson, 277 N.W.2d at 718 (citing Valley State Bank v. Farmers State Bank, 87 S.D. 614, 621, 213 N.W.2d 459, 463 (1973)).
We are convinced, in the present case, especially when viewed against the backdrop of unsettled facts, that Commission was required by law, via due process constitutional mandate, to grant Plaintiffs a hearing before termination of cabin site permits. SDCL 1-26-1(2). Contested case provisions should have been utilized and although Commission did give Plaintiffs a hearing, absent findings of fact and conclusions of law, a formal Commission decision never existed. Johnson v. Skelly Oil Co., 359 N.W.2d 130 (S.D.1984); Department of Pub. Safety v. Eastman, 273 N.W.2d 159 (S.D.1978); SDCL 1-26-25.6
We also hold that the circuit court misinterpreted SDCL 1-26-30.1.7 A party is not commanded to file a proposed decision when an agency fails to act in a contested case. Instead, the statute, by its plain terms, stated that an agency’s failure to make and file a decision “shall entitle a person ... to appeal” and “such person may present to the agency a proposed deci-sion_” SDCL 1-26-30.1 (emphasis added). The words “shall entitle” and “may” are permissive and indicate that Plaintiffs could have proceeded in that fashion if they so chose. See Sioux Valley Hosp. Ass’n v. Bryan, 399 N.W.2d 352, 354 (S.D.1987). See also In re Silver King Mines, 323 N.W.2d 858, 860 (S.D.1982) (where we noted “that SDCL 1-26-30.1 allows appeals from an inferred decision....”) (emphasis added).8
[495]*495Additionally, Plaintiffs cabin site leases are plainly licenses, defined by SDCL 1-26-1(3) as “includftng] the whole or part of any agency permit, certificate, approval, registration, charter, or similar form of permission required by law[.]” See generally 1 Am.Jur.2d Administrative Law § 140, at 949-50 (1962); 53 C.J.S. Licenses § 1 (1948). As per SDCL 1-26-27, “[w]hen the grant, denial, or renewal of a license is required to be preceded by notice and opportunity for hearing, or an applicant, a party or an agency requests a hearing, the provisions of this chapter concerning contested cases apply.” Contested case provisions are presently applicable on the dual grounds that (1) Commission action was required to be preceded by notice and opportunity for hearing; and (2) Plaintiffs requested a hearing addressing Commission’s termination decision.
Accordingly, we reverse the circuit court’s ruling and remand to the court directing it to remand the case to Commission for preparation of findings of fact and conclusions of law. The circuit court is also instructed to stay proceedings relating to Plaintiffs’ estoppel and other claims pending receipt of findings and conclusions from Commission.
Second Administrative Claim.
This claim involves Commission’s March 1984 decision, made at a meeting in Rapid City while Moulton I was before this Court, to increase cabin site rents from $35 to $375-$500 yearly. Plaintiffs appealed to the circuit court pursuant to SDCL ch. 1-26 alleging they were entitled to a hearing as rental increases constituted a contested case. The circuit court, ruling that a contested case did not exist, dismissed Plaintiffs’ appeal. Plaintiffs appeal to this Court advocating that a contested case does exist. Defendants filed notice of review alleging that Plaintiffs possess no property interest which is an element necessary to trigger the contested case procedure of SDCL ch. 1-26 and although the circuit court correctly dismissed Plaintiffs’ appeal, it did so for the wrong reason. We hold that the 1984 cabin site rental increase was improper, which renders resolution of whether said increase is a contested case unnecessary.
In our discussion of Plaintiffs’ first administrative claim, we identified termination of cabin site leases as a license proceeding requiring application of contested case provisions. This Court, in Silver King, 323 N.W.2d 858, set forth the rule that an existing license remains intact “ ‘until the entire appellate process is completed by the courts.’ ” Id. at 860 (quoting In re Silver King Mines, 315 N.W.2d 689, 693 (S.D.1982) (Morgan, J., dissenting)). Consequently, Commission’s 1984 rental increase, instituted during the pendency of Moulton I, 363 N.W.2d 405, was improper. Further, Commission is also precluded from increasing cabin site rents until a final determination is entered in this matter. See Silver King, 323 N.W.2d at 860.
Due to our method of disposition of this administrative claim, we need not decide if Commission’s 1984 rental increase mandates implementation of contested case provisions. We do, however, express that modification of cabin site permit terms has characteristics of a license proceeding through which contested case provisions may be triggered, upon request, to the agency, for a hearing. See SDCL 1-26-27,9 If Plaintiffs do succeed on their estoppel claim, they would be well advised to exhaust administrative remedies before redress is sought in the courts. See SDCL 1-26-30.
Lastly, we wish to state that while a plethora of facts were advocated by both parties, no findings of fact nor conclusions of law were ever entered by an administrative agency or a circuit court. Simply put, the facts have never been found, making resolution of legal claims well nigh impossible. It is this total absence of fact-finding which demands that issues one and two (as identified in the Procedural History/Issues section of this opinion) be reversed and [496]*496remanded in accordance with the dictates of this decision. Issue three is reversed.
MORGAN, SABERS, and MILLER, JJ., concur.
WUEST, C.J., dissents.