This is an appeal from an order of the circuit court which denied the motion of Black Hills Alliance (appellant) to stay the uranium exploration activities of appellee Silver King Mines pending the outcome of the litigation challenging the legality of the renewal of Silver King Mines’ uranium exploration permit.
Silver King Mines was initially issued a one-year uranium exploration permit in South Dakota in January of 1979. In November of 1979, Silver King Mines applied for renewal of its permit. Appellant challenged the issuance of the renewal at a contested hearing before the appellees South Dakota State Conservation Commission and South Dakota Division of Conservation in January of 1980. The renewal was granted in March of 1980.
Appellant appealed to circuit court the agency decision renewing the permit. It also moved under SDCL 1-26-32 for a stay of Silver King Mines’ uranium mining activities pending the outcome of the appeal. *690The circuit court denied the motion for stay on the ground that it did not have authority to issue such an order under SDCL 1-26-28. The circuit court also affirmed the findings of fact and conclusions of law of the administrative hearing which granted the permit renewal. Appellant appeals only from the order denying the motion for stay.
The threshold question is whether the appeal should be dismissed for mootness, since the 1980 permit year has already passed. This court has recognized that “an appeal will be dismissed as moot where, before the appellate decision, there has been a change of circumstances or the occurrence of an event by which the actual controversy ceases and it becomes impossible for the appellate court to grant effectual relief.” Rapid City Journal v. Circuit Court, etc., 283 N.W.2d 563, 565 (S.D.1979). See also Stanley County School v. Stanley County Ed., 310 N.W.2d 162 (S.D.1981); Campbell v. Fritzsche, 78 S.D. 593, 105 N.W.2d 675 (1960). Applying this test, the issue is technically moot for the permit in question has expired and the 1981 permit has already been granted.
This court has recognized a public interest exception to this general rule, however. The policy underlying this exception was summarized as follows in Stanley County, supra at 163: quoting from 5 Am.Jur.2d Appeal and Error § 768 (1962).
“[i]t is a well-established rule that an appellate court may retain an appeal for hearing and determination if it involves questions of public interest even though it has become moot so far as the particular action or the parties are concerned .... The decision as to whether to retain a moot case in order to pass on a question of public interest lies in the discretion of the court and generally a court will determine a moot question of public importance if it feels that the value of its determination as a precedent is sufficient to overcome the rule against considering moot questions.. . . ”
The public interest exception will be invoked only if the following three criteria are established: “(1) general public importance, (2) probable future recurrence, and (3) probable future mootness.” Stanley County, supra at 164, quoting from Anderson v. Kennedy, 264 N.W.2d 714, 717 (S.D.1978).
The first prong of the test is satisfied, because recently uranium exploration has been a subject of substantial public controversy in South Dakota. The question concerning the power of the circuit court to stay uranium exploration pending renewal of an existing license is a very important question. The second and third prongs are met, since the question of the circuit court’s power to stay uranium exploration will recurrently become moot before being decided on appeal, because each permit is issued for a one-year period. In light of the controversial nature of uranium mining, it is likely that this question will recur in the future.*
The second issue is whether SDCL 1-26-28 precludes the authority of the circuit court to grant a stay of Silver King Mines’ uranium exploration activities pending appeal of the renewal application. SDCL 1-26-28 provides:
When a licensee has made timely and sufficient application for the renewal of a license or a new license with reference to any activity of a continuing nature, the existing license does not expire, until the application has been finally determined by the agency, and, in case the application is denied or the terms of the new license limited, until the last day for seeking review of the agency order or a later date fixed by order of the reviewing court, (emphasis added)
*691Appellees contend that under this statute, the 1979 license does not expire until the renewal application is “finally determined” either upon complete review within the appellate process or until the time for appeal has passed, if no appeal is taken. See Wentzel v. Huebner, 78 S.D. 471, 104 N.W.2d 476 (1960). We do not agree.
In Wenzel, we held that an insurance company’s obligation to pay a tort judgment “shall have been finally determined” as of the date when there has been a complete review within the appellate process or when the time for appeal has passed. We have no quarrel with the holding of Wenzel, but we submit that it sheds no light on the Administrative Procedures Act. The Act provides for the extension of an existing license until the new or renewal application has been “finally determined by the agency.” SDCL 1-26-28. The term “agency” as used in the context of the Administrative Procedures Act is defined in SDCL 1-26-1(1) as:
[E]ach association, authority, board, commission, committee, council, department, division, office, officer, task force or other agent of the state vested with the authority to exercise any portion of the state’s sovereignty. The term does not include the Legislature, the unified judicial system, any unit of local government or any agency under the jurisdiction of such exempt departments and units unless the department, unit or agency is specifically made subject to this chapter by statute[.]
In this instance, the agency is the State Conservation Commission which finally determined the matter by granting the renewal application in March of 1980. The agency could not be the circuit court or this court, since the unified judicial system is specifically excluded in the definition of agency. To require appellant to wait to request a stay until the renewal application has been finally determined on appeal would defeat the purpose underlying the stay.
This court has recognized that in determining the intention of the legislature we will presume that the words of the statute have been used to convey their ordinary, popular meaning. Oahe Conservancy Subdistrict v. Janklow, 308 N.W.2d 559 (S.D.1981); Wood v. Waggoner, 67 S.D. 365, 293 N.W. 188 (1940). It is a fundamental rule of statutory construction that all provisions within a statute must be given effect, if possible. State v. Heisinger, 252 N.W.2d 899 (S.D.1977).
The plain meaning of SDCL 1 — 26-28, giving effect to all provisions within the statute, is that where timely and sufficient application for renewal is made, the existing application does not expire until the application is finally determined by the agency, or, if the application is denied or. the terms of the new license are limited, for a limited additional period. It would be contrary to the plain meaning of the statute to imply that final determination refers to the completion of all judicial appeals, when the statute specifically states “finally determined by the agency.” Therefore, the initial 1979 exploration permit expired in March of 1980 when the State Conservation Commission made its final determination granting the renewal license. Appellant was then entitled to appeal from this determination to the circuit court under SDCL 1-26-30.2 and to request the circuit court to grant a further stay of proceedings under SDCL 1-26-32. The circuit court erred in refusing to determine within its discretion whether a further stay under SDCL 1 — 26-32 was appropriate in this case.
We would reverse the order of the circuit court denying a stay; however, because the action which the appellants sought to restrain, i.e., uranium exploration under their 1980 permit, has passed, the stay cannot be given. We do not remand this case for further proceedings and we dismiss the appeal.
WOLLMAN, C. J., and FOSHEIM, J., concur. HENDERSON, J., concurs specially. MORGAN, J., dissents.Camp v. Bjerke, 273 N.W.2d 161 (S.D.1978), is inapposite. In the case before us, appellant contested the 1981 renewal at the administrative hearing. In light of the circuit court’s prior refusal to stay the uranium mining activities pending appeal, it would have been futile for appellant to appeal the renewal to the circuit court. We will not require a party to a lawsuit to perform a futile act to preserve their right to appeal.