Callahan, J.
The plaintiffs, William P. Gelinas and Morton Weiner, challenge the trial court’s refusal to issue a writ of mandamus directing the defendants, the town of West Hartford and its town planner, Donald Foster, (town), to grant their site plan application for premises known as 115-121 Park Road, West Hartford. Gelinas also challenges the propriety of the trial court’s injunctive and penalty orders. In its appeal, the town challenges the refusal of the trial court to grant certain injunctive relief against Gelinas.1
In their appeal, the plaintiffs jointly claim that the trial court improperly concluded: (1) that the town’s failure to render a decision on their site plan application did not result in automatic approval of their application pursuant to General Statutes §§ 8-3 (g) and 8-7d; (2) that the plaintiffs were not entitled to a writ of mandamus directing the town to grant their site plan application; and (3) that an injunction should be issued against Gelinas because there was insufficient evidence that the uses of the subject property enjoined were illegal or, in the alternative, because the town was estopped from seeking an injunction because it had issued various permits for work in areas in Gelinas’ building that the town contended had been put to illegal uses. In his amended appeal, Gelinas claims that the trial court improperly denied his motion to open and correct the judgment regarding the defendants’ counterclaim. Specifically, Gelinas contends that the [578]*578trial court improperly: (1) assessed a daily fine for wilful violation of zoning ordinances pursuant to General Statutes § 8-12; (2) computed the time period during which it assessed the daily fine; and (3) issued an injunctive order overly broad in its scope and application. On the plaintiffs’ appeal, we affirm the judgment of the trial court on all issues except its assessment of daily fines for wilful violation of the West Hartford zoning ordinances. We remand this case to the trial court to vacate the fines and to determine whether to assess civil penalties pursuant to § 8-12.
The town’s appeal challenges the trial court’s denial of a request for an injunction against a change in the use of the basement of Gelinas’ building. We agree with the town on that issue, reverse the judgment of the trial court, and remand the case to the trial court for further proceedings regarding the town’s request for an injunction against a change in the use of the basement.
I
The Plaintiffs’ Appeal
Since December, 1986, Gelinas has owned a two-story building, located at 119-121 Park Road, West Hartford, that had formerly been owned by a fraternal organization and used for large indoor meetings and events. During the early part of 1987, he made alterations to the building including the removal of a first floor assembly hall stage and the construction of two floors of offices in place of the stage and a part of the assembly hall. Thereafter, on June 24,1987, Gelinas applied for a building permit to make changes to the interior of the building. Believing that the proposed changes constituted a change in use, town officials inspected the property and discovered that much of the work for which a permit was sought had already been completed and was in violation of the zoning ordinances and the [579]*579building code.2 Town officials thereupon posted “do not occupy” and “stop work” orders at the site, notified Gelinas that he was in violation of the zoning and building codes and that he must obtain site plan approval, permits and inspections, initiated a prosecution for the building code violations in the housing court, and ordered Gelinas to return the property to its prior condition. Gelinas subsequently was arrested for the building code violations and, on January 21, 1988, the housing court granted him accelerated rehabilitation. As a condition of accelerated rehabilitation, Gelinas was required, within two years, either to obtain site plan approval and building permits for the changes to the building or to return the property to its condition as of January, 1987. Although no finding was ever made [580]*580that he had fulfilled either condition, the charges against Gelinas were eventually dismissed.3
Weiner owned property located at 115-117 Park Road. The town planning office received his application for site plan approval for a driveway repair on November 17, 1987. On the same date, the town received Gelinas’ site plan application for regrading, repaving and storm sewer work at 119-121 Park Road. Thereafter, on February 29,1988, the plaintiffs filed a revised site plan application covering their joint properties.
The revised site plan was not approved, denied or modified, and in June, 1990, the plaintiffs brought this mandamus action against the town.4 In the mandamus action, the plaintiffs sought a certificate of zoning approval for their February 29,1988 joint revised site plan application pursuant to §§ 8-3 (g)5 and 8-7d,6 which [581]*581provide that a site plan is presumed to be approved unless a decision to deny or modify it is rendered within sixty-five days after receipt of the application.7 In an extensive oral decision, the trial court denied the relief sought by Gelinas and Weiner.
The town had filed a counterclaim in the mandamus action alleging that Gelinas had altered the building without first obtaining site plan approval and building permits, had used the building without first obtaining a certificate of occupancy, and had failed to comply with orders to discontinue or remedy the zoning violations. [582]*582Pursuant to § 8-12,8 the town sought injunctive relief to restrain Gelinas from occupying the parts of the building that had been altered and an order that he: correct the building code violations; remove illegal alterations; pay a civil penalty of $2500, costs and attorney’s fees; pay a fine of $100 per day from June 29, 1987, to the date that the zoning violations were corrected; and pay a fíne of $250 per day from December 5,1989, to the date that certain other wilful zoning violations were corrected.9 In a written memorandum [583]*583of decision, the trial court ordered much of the relief sought by the town.10
A
The plaintiffs first claim that the trial court improperly concluded that the town’s failure to render a decision on their site plan application did not result in automatic approval of their application pursuant to §§ 8-3 (g) and 8-7d. The plaintiffs contend that the decisions in SSM Associates Limited Partnership v. Plan & Zoning Commission, 211 Conn. 331, 335-37, 559 A.2d 196 (1989), and Carr v. Woolwich, 7 Conn. App. 684, 699-701, 510 A.2d 1358, cert. denied, 201 Conn. 804, 513 A.2d 698 (1986), control this case. We disagree.
The trial court found, in the instant case, that the alterations to the property had been made before Gelinas had applied for the required permits and also that he had failed to identify the actual and proposed uses of the property. He anomalously sought approval therefore of an application to allow alterations to a building that had already been extensively altered without the necessary permits and had been occupied without a certificate of occupancy. These circumstances distinguish the present case from SSM Associates Limited Partnership and Carr, and require that we consider for the first time the meaning of the word “proposed” as used in §§ 8-3 (g) and 8-7d (b).
[584]*584“Words in a statute must be given their plain and ordinary meaning . . . unless the context indicates that a different meaning was intended.” All Brand Importers, Inc. v. Department of Liquor Control, 213 Conn. 184, 194, 567 A.2d 1156 (1989). “No word or phrase in a statute is to be rendered mere surplusage.” Rydingsword v. Liberty Mutual Ins. Co., 224 Conn. 8, 16, 615 A.2d 1032 (1992). The use of the adjective “proposed” indicates that the legislature meant to distinguish planned structures, alterations or uses from structures, alterations or uses that have already been fully or significantly implemented. The use of the adjective “proposed” signifies that the building, use or structure involved in the application is forthcoming, as opposed to a building, use or structure that, as in this case, has already been significantly altered without the required building permits or zoning approvals. We are not persuaded that the legislature intended that §§ 8-3 (g) and 8-7d (b) mandate automatic approval of site plan applications filed after building alterations and changes in uses have already been significantly implemented without the required building permits or zoning approval.11 Because the plaintiffs did not file a site plan application for “a proposed building, use or structure,” we, therefore, agree with the trial court and conclude that the town’s failure to render a decision on the plaintiffs’ site plan application within the prescribed time limits did not result in an automatic approval of the application pursuant to §§ 8-3 (g) and 8-7d.12
[585]*585B
The plaintiffs next claim that the trial court improperly concluded that they were not entitled to a writ of mandamus directing the town to grant their site plan application. See General Statutes § 52-485 (a);13 Kosinski v. Lawlor, 177 Conn. 420, 426-27, 418 A.2d 66 (1979). We disagree.
[586]*586“Mandamus is an extraordinary remedy. It is designed to enforce a plain positive duty. The writ will issue only when the person against whom it is directed is under a clear legal obligation to perform the act compelled and the party seeking the writ has a clear legal right to the performance.” (Internal quotation marks omitted.) McAllister v. Nichols, 193 Conn. 168, 171, 474 A.2d 792 (1984). “The[se] . . . requirements are concededly met, once the statutory language is determined to be mandatory.” Vartuli v. Sotire, 192 Conn. 353, 365, 472 A.2d 336 (1984). We have concluded that §§ 8-3 (g) and 8-7d (b) “imposed a mandatory time frame of sixty-five days on local site plan approvals. Id., 359-62; see also Carr v. Woolwich, supra, 694-95.” SSM Associates Limited Partnership v. Plan & Zoning Commission, supra, 335.
The plaintiffs contend that timetables provided in the land use statutes evidence the legislature’s intent to protect the interests of applicants from abuses of municipal authority, such as the delays in the processing of the application in this case that allegedly subjected Gelinas to civil and criminal penalties. They argue that a writ of mandamus was the proper remedy for the town’s failure to act within the prescribed time limits. The trial court found, however, that the application was incomplete because Gelinas had never provided the town with information as to the actual or proposed use of the property, and that he did not seek the certificate of approval in a timely manner, that is, before he did the work.14 The trial court found further [587]*587that the clean hands doctrine defeated the plaintiffs’ request for a writ of mandamus. “One who seeks equity-must also do equity and expect that equity will be done for all.” LaCroix v. LaCroix, 189 Conn. 685, 689, 457 A.2d 1076 (1983).
In light of our conclusion in part I A that the plaintiffs’ site plan application did not comply with the requirements of §§ 8-3 (g) and 8-7d (b), they have failed to establish the necessary predicate for their claimed entitlement to a writ of mandamus. We conclude, therefore, that the trial court properly refused to order the extraordinary remedy of mandamus.
C
The plaintiffs next dispute the propriety of the injunction that the trial court issued against Gelinas pursuant to § 8-12 in rendering its judgment for the defendants on their counterclaim. The plaintiffs contend that: (1) there was insufficient evidence to support the trial court’s finding that the uses to which the subject building had been put were illegal; or (2) in the alternative, the town was estopped from seeking an injunction because it had issued various carpentry, air conditioning and electrical permits for areas in the building that the town then maintained had been put to illegal uses. We disagree, and address each argument in turn.
The plaintiffs argue that the evidence was insufficient to support the decision by the trial court to grant the injunctive relief, pursuant to § 8-12, as requested by the town in the counterclaim.15 We do not agree.
[588]*588In seeking an injunction pursuant to § 8-12, the town is relieved of the normal burden of proving irreparable harm and the lack of an adequate remedy at law because § 8-12 by implication assumes that no adequate alternative remedy exists and that the injury was irreparable. Conservation Commission v. Price, 193 Conn. 414, 429, 479 A.2d 187 (1984). The town need prove only that the statutes or ordinances were violated. Id. The proof of violations does not, however, deprive the court of discretion and does not obligate the court mechanically to grant the requested injunction for every violation. Id., 430. Although this eourt will generally refrain from interfering with a trial court’s exercise of discretion; State v. Martin, 201 Conn. 74, 88, 513 A.2d 116 (1986); discretion is to be exercised “in conformity with the spirit of the law and in a manner to subserve and not to impede or defeat the ends of substantial justice.” (Internal quotation marks omitted.) Hammerberg v. Leinert, 132 Conn. 596, 604, 46 A.2d 420 (1946).
The zoning code of the town provides that no structure shall be expanded or structurally altered until a certificate of site plan approval has been issued. West Hartford Code § 177-38; see also § 177-6 (B) and (C). Additionally, no structure may be used or changed to another use until the building inspector has issued a certificate of occupancy, certifying that the zoning ordinances have been complied with in full, including any conditions attached to any site plan approval. West Hartford Code § 177-39. Section 177-41 of the zoning code specifies the content required in applications for zoning and building permits. Section 111.1 of the state [589]*589building code provides in relevant part that “no building or structure shall be constructed; altered . . . have its use changed . . . until an application has been filed with the building official and a permit issued.”
The trial court found that Gelinas had removed a stage and, in its place, added six offices, three on each of two levels of the subject building. The trial court found further that Gelinas had admittedly made the alterations and additions without first obtaining the requisite permits, thereby violating §§ 177-38 and 177-39 of the zoning code and § 111.1 of the building code.
We conclude that the trial court properly exercised its discretion in fashioning its orders for prohibitory and mandatory injunctive relief for violations of the building code that had occurred prior to the approval of a site plan application as required by law.
The plaintiffs argue in the alternative that the town was estopped from seeking an injunction because it had issued various mechanical permits for work in areas of the building that the town then maintained had been put to illegal uses.16 The plaintiffs equate the permit approvals for work in specific areas of the building with zoning approval that would estop the town from obtaining injunctive relief.
[590]*590“Estoppel against municipalities is . . . limited and may be invoked against the enforcement of zoning regulations (1) only with great caution, (2) only when the resulting violation has been unjustifiably induced by an agent having authority in such matters, and (3) only when special circumstances make it highly inequitable or oppressive to enforce the regulations. Dupuis v. Submarine Base Credit Union, Inc., [170 Conn. 344, 354, 365 A.2d 1093 (1976)].” Zoning Commission v. Lescynski, 188 Conn. 724, 731-32, 453 A.2d 1144 (1982); see also West Hartford v. Gelinas, 18 Conn. App. 688, 691, 559 A.2d 1176 (1989). To prevail on the claim that the town is estopped from seeking an injunction, Gelinas must establish that an agent of the town induced him to believe that certain facts existed and to act on that belief, and that he changed his position in reliance upon those facts, thereby incurring some injury. Zoning Commission v. Lescynski, supra, 731.
Gelinas began work on the premises before he had submitted the June 24, 1987 building permit application, the approval of which would have allowed him to commence structural alterations to the interior of the building. The zoning enforcement officer testified that the building permit application to replace windows, to do electrical work, and to make interior alterations had been denied within thirty days of submission. He also testified, however, that: a permit for a heat pump had been issued, but only because unauthorized work on the new second floor had cut off the heat source that had previously protected the fire sprinkler system from freezing; one electrical permit had been issued for a change of service location only; and a permit for fire damage repair that did not involve any room reconfiguration had been issued. Although § 8-3 (f)17 prohibits [591]*591town officials from issuing building permits of any kind where zoning violations exist, the issuance of certain permits for these limited purposes could not have led Gelinas to believe that he had carte blanche to proceed with extensive structural alterations. We conclude, therefore, that the plaintiffs have not established that the subsequent building and zoning code violations by Gelinas had been induced by an agent of the town. Accordingly, their claim of estoppel must fail.
D
Gelinas also claims in his amended appeal that the trial court abused its discretion by refusing to open the judgment in which it had assessed a daily fine of $100 from June 29, 1987, to June 15, 1990, for the “wilful violation” of zoning ordinances pursuant to General Statutes § 8-12.18 We agree.
The gravamen of Gelinas’ claim is that § 8-12 provides for the imposition of fines for “wilful offenses” only if a defendant has been convicted of a criminal offense. Gelinas maintains that if he was liable for any penalty at all, only the language in § 8-1219 concerning civil penalties of “not less than ten nor more than one hundred dollars for each day that such violation [592]*592continues” and “a civil penalty not to exceed two thousand five hundred dollars” would be applicable on these facts. Gelinas contends that the legislature did not intend that the remedies in § 8-12 for wilful violations be cumulative or interchangeable with those for nonwilful violations.20 The town contends, to the contrary, that § 8-12 affords broad discretion to the trial court in fashioning appropriate remedies for the violation of zoning ordinances. The town argues that the trial court imposed the maximum allowable civil fine of $100 or, in the alternative, that the availability of a fine as a penalty in a criminal proceeding for “wilful violations” does not preclude judicial authority from imposing fines in other appropriate circumstances. According to the town, therefore, reasons of judicial economy militate toward a construction that allows the imposition of all fines for zoning violations in a single action.
“A motion to open and vacate a judgment ... is addressed to the [trial] court’s discretion, and the action of the trial court will not be disturbed on appeal unless it acted unreasonably and in clear abuse of its discretion. ... In determining whether the trial court abused its discretion, this court must make every reasonable presumption in favor of its action. . . . The manner in which [this] discretion is exercised will not be disturbed so long as the court could reasonably conclude as it did.” (Citations omitted; internal quotation [593]*593marks omitted.) Walton v. New Hartford, 223 Conn. 155, 169-70, 612 A.2d 1153 (1992).
It is undisputed that the trial court imposed the fine for “wilful violation” of the zoning ordinances. Section 8-12 unambiguously provides for both civil and criminal remedies. It does not, however, authorize a court to impose the same penalties in a civil proceeding that it could impose in a criminal proceeding. To construe the statute as the town proposes would be to render a nullity the necessity for a criminal prosecution as a predicate for the imposition of fines for a “wilful violation.” We conclude, therefore, that the trial court improperly denied Gelinas’ motion to open the judgment assessing criminal penalties imposed pursuant to § 8-12, in order to consider whether the predicate conviction of a criminal offense existed. Accordingly, we reverse in part the judgment of the trial court and remand the case to that court with direction to vacate the daily fine of $100 for “wilful offenses” and to impose such civil penalties pursuant to § 8-12 as the trial court may deem appropriate in the proper exercise of its discretion.21
E
Gelinas finally alleges that the trial court abused its discretion because its injunctive order was so overly broad in its scope and application as to deprive him permanently of the use of an entire floor of the subject building. Gelinas requested that the trial court limit the scope of the injunction, as it related to the first floor, to the area formerly occupied by the stage. The trial court, however, enjoined the use of the entire first floor. Contrary to Gelinas’ assertions as to the unreasonableness of the court’s order, however, the trial court allowed him either to take the necessary steps within [594]*594sixty days to obtain approval to use the newly constructed first floor offices or to remove them within six months and reapply for zoning approval for proposed uses for the entire area of the first floor.
We conclude, therefore, that the trial court did not abuse its discretion in framing the scope of the injunctive relief granted.
II
The Town’s Appeal
The town claims in its appeal that the trial court improperly denied the town’s request for an injunction against a use change in the basement of Gelinas’ building that was in violation of § 177-39 of the West Hartford Code. We agree.
The town introduced evidence that Gelinas had illegally introduced commercial uses into the basement beginning in February, 1987, and had entered into additional commercial leases in 1988 and 1989. These commercial uses were in addition to the valid nonconforming assembly hall main use and dining and kitchen accessory uses by the tenant fraternal organization. On July 10, 1987, the assistant zoning enforcement officer ordered Gelinas to return the entire basement to the prior valid nonconforming uses and issued him an infraction ticket. It is undisputed that Gelinas did not appeal the order.
The town consequently requested an injunction, pursuant to § 8-12, to halt the changed uses in the basement for which a certificate of occupancy had not been issued; West Hartford Code § 177-39; and for which a cease and desist order had been issued on July 10, 1987. The trial court denied the request because it concluded that the evidence concerning the allegations of nonconforming uses and structural changes in the basement was contradictory and inconclusive.
[595]*595The town argues that injunctive relief should have been granted because it is the proper remedy if a party has failed to appeal a cease and desist order of a zoning enforcement official. “The cease and desist order was, in effect, a determination that the defendant did not have a valid nonconforming use.” Bianco v. Darien, 157 Conn. 548, 558, 254 A.2d 898 (1969).
General Statutes § 8-6 (1) provides that a zoning board of appeals shall have the power “[t]o hear and decide appeals where it is alleged that there is an error in any order, requirement or decision” made by, inter alios, the zoning enforcement officer. Section 177-49 of the West Hartford Code provides that the zoning board of appeals shall have the power and duty “[t]o hear and decide appeals where it is alleged that there is an error in any order, requirement or decision made by any official charged with the enforcement and administration of the Zoning Ordinance.” We have held that the statutory scheme reflects the legislative intent that the issue of what constitutes a nonconforming use should be resolved in the first instance by local officials. Greenwich v. Kristoff, 180 Conn. 575, 578, 430 A.2d 1294 (1980); see also General Statutes § 8-7. “[Wjhen a party has a statutory right of appeal from the decision of an administrative officer or agency, he may not, instead of appealing, bring an independent action to test the very issue which the appeal was designed to test.” Country Lands, Inc. v. Swinnerton, 151 Conn. 27, 33, 193 A.2d 483 (1963); Cummings v. Tripp, 204 Conn. 67, 78, 527 A.2d 1230 (1987). Likewise, the validity of the order may not be contested if zoning officials seek its enforcement after a violator has failed to appeal.
However, “[e]ven in an action brought by a zoning enforcement officer to require conformity with the zoning regulations, the granting of injunctive relief, which must be compatible with the equities of the case, rests [596]*596within the trial court’s sound discretion. Dupuis v. Submarine Base Credit Union, Inc., supra, 356. Those equities should take into account the gravity and wilfulness of the violation, as well as the potential harm to the defendants. Berin v. Olson, 183 Conn. 337, 343, 439 A.2d 357 (1981).” Johnson v. Murzyn, 1 Conn. App. 176, 183, 469 A.2d 1227, cert. denied, 192 Conn. 802, 471 A.2d 244 (1984). A review of the record discloses that the equities in this case patently lie with the town. The record clearly reveals that Gelinas installed commercial ventures in the basement of the subject building knowing full well that he was flagrantly violating the West Hartford zoning ordinances.
We conclude, therefore, that the trial court abused its discretion by refusing to render judgment entitling the town to injunctive relief from the unauthorized business use of the basement. Accordingly, we reverse the judgment of the trial court on this issue and remand the case to the trial court with direction to render judgment for the town consistent with this opinion. We leave it to the discretion of the trial court to fashion the scope of the injunctive relief to which the town is entitled.
The judgment is reversed in part with respect to the plaintiffs’ appeal, the judgment is reversed with respect to the town’s appeal, and. the case is remanded for further proceedings in accordance with this opinion.
In this opinion Peters, C. J., Borden and Katz, Js. concurred.