OPINION
ROBINSON, J.{1} This case concerns the interpretation of a collective bargaining agreement entered into in 1996 between the University of New Mexico (the University) and the University of New Mexico Police Officer’s Association (the Association). The trial court determined that the University breached its agreement with the Association by underpaying police officers and awarded damages accordingly. On appeal, the University argues that (1) under NMSA 1978, § 37-l-23(A) (1976), it is immune from suit, and (2) the action is barred because the Association failed to exhaust its administrative remedies. We affirm.
Background
{2} The trial court articulated thirty-two findings of fact, which provided an extensive background for its rationale. The University challenges only one finding of fact. We set the background for this case based upon the remaining facts as found by the trial court. See Tres Ladrones, Inc. v. Fitch, 1999-NMCA-076, ¶ 17, 127 N.M. 437, 982 P.2d 488 (stating that a trial court’s unchallenged findings of fact are binding on appeal). The University recognized in the early 1990s that its system of classifying and compensating employees was in “a state of disarray” due to significant changes in both its operations and in the nature of work in general. It hired an outside organization to study the wages being paid to its employees. The purpose of the UNMPact, as the study came to be called, was to address the inadequacy of University pay in light of the wages paid in comparable markets. The UNMPact classified employees and proposed to pay wages in accordance with comparable markets and the wages paid for similar work.
{3} While the study was in progress, the Association was organized to represent the police officers and sergeants of the University’s police force. In 1996, the Association began negotiations with the University regarding the Association’s first collective bargaining agreement that would cover its members. However, by the fall of 1996, the parties had reached an impasse on the issue of officer salaries.
{4} On October 26, 1996, Susan Carkeek, Associate Vice President and Director of Human Resources for the University, gave a presentation concerning the UNMPact to officials of the Association. Although, conflicting testimony was presented at trial as to the substance of this presentation, the trial court expressly found that during Carkeek’s presentation, representatives of the Association were told that police officer wages would be increased to an amount equal to the average salary of first-year officers for the Albuquerque Police Department and the Bernalillo County Sheriffs Department, effective January 1, 1997. Carkeek was specifically asked whether a comparison would be made between the Association’s wages and those of smaller departments. She replied “No,” that the marketplace used for this analysis would be the Albuquerque Police Department and the Bernalillo County Sheriffs Department. The average salary then for an entry-level Albuquerque Police Department or Bernalillo County Sheriffs officer was $13.68 per hour.
{5} Association representatives reported to their membership on Carkeek’s presentation, and the members voted to accept an employment contract with the University which included the UNMPact. The vote was based on an express understanding that salaries would be adjusted to $13.68 per hour for those officers not presently earning that wage. The Association ratified its first collective bargaining agreement with the University on November 21, 1996, based on this understanding, and included within that agreement a provision that the parties agreed to fully implement the UNMPact.
{6} In January or February 1997, the University sent individual members of the Association letters informing them of the salary they would receive based on the UNMPact. The police officers also received instructions on filing a request for reconsideration if they objected to the new salary level. The request was to be submitted on a form provided by the University. The trial court explicitly found that the University did not mail any information concerning requests for reconsideration to the Association as required by the collective bargaining agreement. Yet, the trial court found that the Association completed a reconsideration form and submitted it to the University. This last finding is the only one challenged on appeal.
{7} Based on these findings, the trial court concluded that the collective bargaining agreement required the University to pay police officers $13.68 per hour and that the University breached the contract by paying officers less than that amount. In addition, the trial court concluded that the Association did not fail to exhaust its administrative remedies. Indeed, the trial court determined that the Association continually pressured the University, from April 1997 through the time of trial, to pay its police officers the correct wage by means of grievance proceedings, the filing of a Prohibited Practice Complaint with the Public Employee Labor Relations Board, and the exchange of letters with the University.
Section 37-l-23(A) Does Not Immunize the University from this Lawsuit
{8} The University does not challenge the trial court’s finding that the Association was promised that implementation of the UNMPact would result in raising the hourly wage of its member officers to $13.68 per hour. However, it contends enforcement of this representation is barred by Section 37-l-23(A). Under the circumstances of this case, we disagree.
{9} Whether Section 37-l-23(A) bars a particular action is an issue of law that is reviewed de novo on appeal. See Campos de Suenos, Ltd. v. County of Bernalillo, 2001-NMCA-043, ¶ 10, 130 N.M. 563, 28 P.3d 1104 (“[T]he application of the facts of a case to an assertion of immunity, is a legal question that we review de novo.”).
{10} Section 37-l-23(A) provides: “Governmental entities are granted immunity from actions based on contract, except actions based on a valid written contract.” This section has been interpreted to require only that there be a valid written contract underlying a claim. See Treloar v. County of Chaves, 2001-NMCA-074, ¶16, 130 N.M. 794, 32 P.3d 803. Thus, when an action arises from a valid written contract, the action is not barred by Section 37-l-23(A) even though the action involves equitable claims such as reformation based on mutual mistake, see Ballard v. Chavez, 117 N.M. 1, 2 n. 2, 868 P.2d 646, 647 n. 2 (1994), or breach of an implied warranty, see Vinnell Corp. v. State, 85 N.M. 311, 312, 512 P.2d 71, 72 (1973) (holding that highway construction contractor who is misled by incorrect plans and specifications may recover for the resulting extra expenses). More recently, the New Mexico Supreme Court indicated that if there is a valid written contract, Section 37-1-23(A) will not bar litigation that may involve a dispute concerning the terms and conditions of the contract. See Handmaker v. Henney, 1999-NMSC-043, ¶¶ 17-20, 128 N.M. 328, 992 P.2d 879.
{11} The University characterizes this dispute as involving “a contract term that was established only through alleged oral representations.” We do not agree. It is undisputed that there is a valid written contract between the Association and the University. The contract provides that “[t]he parties agree to participate in and fully implement the UNMPact classification and compensation study.” The question to be resolved by the trial court was what this provision meant to the Association at the time it agreed to the provision. See Maine v. Garvin, 76 N.M. 546, 550-51, 417 P.2d 40, 43 (1966) (“Parol evidence may not be received when its purpose and effect is to contradict, vary, modify, or add to a written agreement, but is generally admissible to supply terms not in the written contract, to explain ambiguities in the written agreement, or to show fraud, misrepresentations, or mistake.”); C.R. Anthony Co. v. Loretto Mall Partners, 112 N.M. 504, 509, 817 P.2d 238, 243 (1991) (“It is important to bear in mind that the meaning the court seeks to determine is the meaning one party (or both parties, as the circumstances may require) attached to a particular term or expression at the time the parties agreed to those provisions.”). In determining what this phrase meant to the parties, the trial court in this case could consider “evidence of the circumstances surrounding the making of the contract and of any relevant usage of trade, course of dealing, and course of performance.” See id. This type of evidence can be used initially to determine whether the provision was ambiguous and, if so, to resolve the ambiguity. Ponder v. State Farm Mut. Auto. Ins. Co., 2000-NMSC-033, ¶ 13, 129 N.M. 698,12 P.3d 960.
{12} The University appears to recognize that the testimony concerning Carkeek’s representations made at the October 26 meeting was offered to clarify the meaning of the contract language concerning the UNMPact. However, it asserts that this approach was rejected by Campos de Sueños, 2001-NMCA-043, ¶ 23, 130 N.M. 563, 28 P.3d 1104. We cannot agree. In Campos de Sueños, the developer of a parcel of land argued that even though there was no written contract between the developer and the county, a series of writings could be used to create a “valid written contract” within the meaning of the statute. Id. ¶ 12. We held that a series of writings did not satisfy the requirement of a written contract. Id. ¶ 19. The portion of the opinion that the University relies on recites one of the contentions of the developer. See id. It does not state this Court’s view. Again, in this case, there was indisputably a valid written contract. The dispute is about the meaning of one provision of that contract. Thus, Campos de Sueños is inapposite. Considering the evidence surrounding the making of the contract, and particularly the representations made by Carkeek, the discussion about the UNMPact, and the agreement to fully implement the UNMPact classification and compensation study, we think the trial court could reasonably conclude that the dispute involves a term of the contract as contemplated in Handmaker. See Handmaker, 1999-NMSC-043, ¶ 20, 128 N.M. 328, 992 P.2d 879.
{13} To bolster its position that immunity is essential, the University argues that the statute was enacted to prevent fraud and to encourage adherence to appropriate processes in governmental contracting. In our view, the overriding fact is that a valid written contract exists. The issue is whether that contract was meant to include the UNMPact and the average starting salary of the police officers as represented to the Association. The overall purpose of the statute, which is to create immunity, Campos de Suenos, 2001-NMCA-043, ¶ 19,130 N.M. 563, 28 P.3d 1104, was not violated by the trial court’s interpretation of the statute and application of the statute to the facts.
Exhaustion of Administrative Remedies
{14} The trial court made two determinations concerning the affirmative defense of exhaustion of remedies. First, the trial court found that the University did not mail any information concerning the request for reconsideration process to the Association as required by Section 38 of the agreement between the parties. Second, the trial court found that the Association completed the reconsideration form and submitted it to the University. On appeal, the University makes both legal and factual arguments. Legally, the University argues that because the individual police officers were notified of the reconsideration process, the Association had actual notice of the process and therefore it was not necessary to provide written notice to the Association. Factually, the University contends the trial court’s finding that the Association submitted a request for reconsideration is not supported by substantial evidence, arguing that the only evidence supporting that finding was based on the members’ belief that the request had been filed.
{15} We turn first to the University’s argument that notice to individual members was legally sufficient. The trial court determined that Section 38 of the collective bargaining agreement required the University to give written notice of the reconsideration process to the Association. The University does not challenge this interpretation of the collective bargaining agreement. Instead, it relies on cases that provide that formal notice may not be required if the party has actual notice. However, none of the cases cited by the University involved a contract that required written notice. The cases involve situations in which a provision of a statute or contract required notice but did not specify the manner in which notice was to be given. See In re Estate of Gaines, 113 N.M. 652, 654-56, 830 P.2d 569, 571-73 (Ct. App.1992) (statute requiring person receive notice held satisfied when the party had been served by both sides in a will contest); State v. Integon Indem. Corp., 105 N.M. 611, 612, 735 P.2d 528, 529 (1987) (actual notice to contractor that he was lowest bidder at the time bids were taken was adequate notice under Public Purchase Act); see also Mega Constr. Co. v. United States, 29 Fed. Cl. 396, 442-43 (1993) (statute requiring request for a final decision on a claim held satisfied when the request can be inferred from circumstances); Bloom Township High Sch. v. Ill. Commerce Comm’n, 309 Ill.App.3d 163, 242 Ill.Dec. 892, 722 N.E.2d 676, 689 (1999) (contract requiring notice held satisfied by verbal and voice mail notice when contract did not require that company provide written notice or dedicated phone line to provide notice). Thus, the cases supplied by the University are inapposite.
{16} Next, we examine the University’s challenge to the trial court’s finding that the Association, and specifically then-President James Daniels, submitted the reconsideration request. We view the evidence in the light most favorable to the trial court to determine whether there is sufficient evidence to support the finding. Lopez v. Adams, 116 N.M. 757, 758, 867 P.2d 427, 428 (Ct.App.1993). Thus, we draw all inferences from the evidence in a manner that will uphold the finding and disregard evidence and inferences to the contrary. Weidler v. Big J Enters. Inc., 1998-NMCA-021, ¶ 30, 124 N.M. 591, 953 P.2d 1089. The Association contends that this issue was not preserved because the University did not make the same substantial evidence argument below that it now makes on appeal. However, the University’s motion for a directed verdict argued that there was no competent evidence to support a finding that the Association’s reconsideration request was submitted. Thus, the issue was brought to the attention of the trial court, and the Association was provided an opportunity to respond.
{17} The trial court heard considerable testimony about the preparation and submission of the reconsideration request. University personnel Carkeek and Shannon Mick both testified that there was no record of the request having been submitted. On the other hand, three police officers testified that they helped prepare the reconsideration request. One of the three testified that he instructed an officer to put the request in President Daniels’ box. In addition, there was testimony that the Association and its members had been informed that the request had been submitted.
{18} The cornerstone of the University’s substantial evidence argument is the testimony of President Daniels. At the time the contract was negotiated and the UNMPact was implemented, Daniels was the president of the Association.
{19} At trial, Daniels testified that he filled out two requests for reconsideration that he could recall. The first was on behalf of one or more detectives, and the second was on behalf of a corporal. On cross-examination by the University, Daniels initially testified that he never saw the request for reconsideration concerning police officers until “just now.” When asked if it was “something he ever submitted on behalf of the police officers,” he testified “No. When I submitted these [referring to the other two requests], I signed them. This one is not signed. I don’t recall submitting a police officer. I recall submitting detectives and a corporal.” Later in his testimony he again stated that he recalled submitting only a couple of requests for reconsideration. Upon redirect by the Association, he did recall that he had seen a request for reconsideration for the police officers earlier when it had been produced previously by the Association during this litigation.
{20} The University views this testimony as establishing that Daniels did not submit the reconsideration request for the police officers. However, on appeal we view the evidence in the light most favorable to the trial court’s decision. Weidler, 1998-NMCA-021, ¶ 30, 124 N.M. 591, 953 P.2d 1089. ' Thus, we view Daniels’ testimony as establishing only that he did not recall filing the reconsideration request on behalf of police officers.
{21} Several other witnesses testified concerning the reconsideration process. Carkeek testified that there were about 2300 reconsideration requests submitted. She was not aware of each and every request that was filed. She denied that any such requests were misplaced or lost. In addition, she testified that employees filing reconsideration requests were not required to go through their supervisors. She also testified that the Association itself did not receive notice of the reconsideration process. In addition, Mick, who oversaw the reconsideration process, testified that approximately 2400 requests were filed. She indicated this was forty percent of the employees affected by the UNMPact. Mick also testified that, even though there were 2400 documents filed and only six or seven people on her staff to process those documents, none of the documents was ever lost or misplaced and they never had any complaints about documents being lost or misplaced. In closing argument, the Association’s lawyer characterized her testimony as unbelievable.
{22} In sharp contrast to this testimony was that of Donald Birge, president of the University Staff Council which represents the non-teaching staff of the University. Birge gave specific examples of erroneous reclassifications that had occurred as part of the UNMPact process. In addition, his testimony that “during the thirty-six to forty-eight times that he helped employees at the university prepare this particular form, that, in fact, it was common to have the documents not filed, to have them lost, to have no recognition of receipt of the documents.”
{23} The evidence, viewed in the light most favorable to the finding, was as follows: The Association had a copy of a request for reconsideration in its files. The University did not. Three people who were members of the Association at the time the request would have been submitted testified about their role in preparing the request. One of the three testified to instructing an officer to put the request in President Daniels’ box, who did not recall submitting the request. A fourth witness, who was not a member of the Association, testified that it was not uncommon for the University to lose reconsideration requests. On the other hand, the University personnel who testified insisted that there were no complaints concerning lost reconsideration requests and that no request was ever lost, despite the large volume of requests and the small number of people available to handle them. On this state of the testimony, we think that the trial court was in the best position to “weigh the testimony, determine the credibility of the witnesses, reconcile inconsistent statements of the witnesses, and determine where the truth lies.” Sanchez v. Homestake Mining Co., 102 N.M. 473, 476, 697 P.2d 156, 159 (Ct.App. 1985). In this situation we defer to the trial court’s resolution of the issue. Id. We hold that the trial court’s finding that the request for reconsideration was filed is supported by substantial evidence and that the Association thereby exhausted its administrative remedies.
Conclusion
{24} In summary, we hold the Association’s action against the University is not barred by Section 37-l-23(A). We further hold that, under the circumstances, the trial court properly rejected the University’s contention that the Association failed to exhaust its administrative remedies. The University failed to pay the police officers their proper wages under the collective bargaining agreement. The judgment of the trial court is affirmed.
{25} IT IS SO ORDERED.
MICHAEL D. BUSTAMANTE, Judge (specially concurring). JONATHAN B. SUTIN, Judge (specially concurring).