GOLDEN, Justice.
Appellants Gene and Dorothy E. Cran-ston (Cranstons) appeal from the trial court’s orders dismissing their complaint against the Weston County Weed and Pest Board (WCWPB) and dismissing their amended complaint against the Weston County Board of Commissioners (Commissioners). The trial court’s dismissals were based on the Cranstons’ failure to serve a separate notice of claim on WCWPB, to show that Weston County owed them a duty of care, and to prove that the county had insurance available to cover appellant’s claim against Weston County.
Appellants raise the following issues:
A. Whether the Weston County Weed and Pest [Board] is a “governmental entity” requiring separate service of a Notice of Claim?
B. Whether Weston County Weed and Pest [Board] is estopped from asserting that it was a separate and distinct governmental entity from the Weston County Board of Commissioners?
C. Whether Appellants substantially complied with W.S. 1-39-113 so as to confer subject matter jurisdiction upon the district court?
D. Whether the Weston County Commissioners waived their immunity from [253]*253liability by purchasing liability insurance?
E. Whether the Weston County Board of Commissioners owe a duty to Plaintiffs in this case?
We affirm the order dismissing appellants’ suit against WCWPB, reverse the order dismissing appellants’ suit against the Commissioners, and remand for further proceedings.
FACTS
Appellants own a ranch adjoining state-owned property in Weston County. Historically, appellants’ source of drinking water has been a well which pumps from an aquifer located beneath the surface of their property. Water from the aquifer has also been used for livestock purposes.
In August, 1987, after noticing that plants in his garden wilted when he watered them, Gene Cranston sent a sample of his tapwater to the Wyoming Department of Agriculture for testing. The test results showed that the water was contaminated with 18 parts per billion of Picloram (tradename “Tordon”), a herbicide used to control broadleaf weeds. The Department of Agriculture advised Cranstons that the amount of Tordon present in their water was sufficient to harm vegetable crops and broadleaf weeds. The Department recommended that the Cranstons find another source of drinking water.
The Cranstons notified the Wyoming Department of Environmental Quality (DEQ) of the contamination problem. After an investigation, the DEQ found that appellee WCWPB was responsible for spraying and applying pellets of the herbicide to the state land adjacent to and upgradient from the Cranstons’ property. This herbicide polluted the groundwater from which the Cranstons obtained their drinking water. The DEQ issued a notice of violation to Weston County for the herbicide pollution.
Cranstons prepared a notice of claim against both the Commissioners and the WCWPB. The notice requested damages of $2 million based on various claims arising from negligent application of the herbicide by WCWPB employees. Cranstons sent a single copy of this document certified mail addressed to “Weston County Commissioners, Weston County Courthouse, Newcastle, Wy. 92701.”
When the claim went unsatisfied, Cran-stons filed suit in district court. Their complaint requested damages for negligence by the Commissioners and WCWPB. Both entities moved to dismiss the complaint, citing immunity under the Wyoming Governmental Claims Act and insufficiency of process.
The trial court found that WCWPB was a separate governmental entity which should have been served with a notice of claim before the suit; that the Commissioners could not be held vicariously liable for the acts and omissions of WCWPB under the doctrine of respondeat superior; that the complaint failed to allege that the County had liability insurance; and that no other exception to the Governmental Claims Act was applicable. The trial court dismissed Cranstons’ complaint, but allowed them to file a claim with WCWPB if they could still do so during the limitations period. See W.S. 1-39-113 (June 1988 Repl.). If not, the court found no just cause for delay and stated it would enter judgment in favor of WCWPB.
Cranstons were given thirty days to file an amended complaint against Weston County. This complaint was required to allege that the Commissioners could be held liable because of insurance coverage. Cranstons were also given the opportunity to discover information about the county’s insurance policies.
Cranstons were unable to file a claim with WCWPB because the two-year limitations period had expired; therefore, they appealed to this court that portion of the trial court’s order granting judgment for WCWPB. Cranstons also filed an amended complaint, which included an allegation of insurance coverage, against the Commissioners. After a hearing the trial court granted the Commissioners’ motion to dismiss the amended complaint. Cranstons appealed from that order, and we now con[254]*254sider all of Cranstons’ issues together in this appeal.
STANDARD OF REVIEW
As a threshold question we must determine whether the trial court’s orders were dismissals under W.R.C.P. 12(b)(6) or whether the motions to dismiss had been converted to motions for summary judgment by the court’s consideration of material outside the pleadings.
The record reveals the following discussion between counsel and the court at the hearing on appellees' first motion to dismiss:
Mr. Hunt [counsel for appellees]: I have a letter that Mrs. Hein has agreed to stipulate to admission of which, it comes from the Farm Bureau Insurance Company, Mountain West Farm Bureau Mutual Insurance Company, whereby the attorney for that company has denied liability on the claims of which it is aware * * *. I offer that to the court to—
Ms. Hein [counsel for appellants]: No objection, Your Honor.
The Court: Okay.
That will convert this from a 12(b) motion to a motion for summary judgment then?
Mr. Hunt: In that it—
The Court: Looks at matters outside the pleadings.
Mr. Hunt: —outside the pleadings. That’s okay with me.
Ms. Hein: That’s not okay with me then. That’s going to change it.
Apparently, no further discussion was held on whether appellees’ motion to dismiss had been converted to a motion for summary judgment. Nor was any determination made on Cranstons’ objection to conversion.
A motion for dismissal under W.R.C.P. 12(b)(6) converts to a motion for summary judgment if the trial court considers matters other than the pleadings. Mostert v. CBL & Associates, 741 P.2d 1090, 1097 (Wyo.1987). For a more thorough explanation of this concept, see also Torrey v. Twiford, 713 P.2d 1160, 1162-63 (Wyo.1986). If the materials considered are affidavits attached to the motion, conversion occurs automatically. Torrey, 713 P.2d at 1165; W.R.C.P. 12(b). If affidavits have not been filed, but other materials are considered, such as discovery documents, conversion does not occur automatically. The court may still treat the motion as one for summary judgment, but the record must demonstrate that the parties had notice of the conversion and that the nonmovant had an opportunity to respond. Torrey, at 1164. See also Kimbley v. City of Green River, 642 P.2d 443, 445 (Wyo.1982), appeal after remand 663 P.2d 871 (Wyo.1983).
In this case, the trial court considered nonaffidavit materials which were outside the pleadings. Counsel for appel-lees presented the court with a letter from their insurance company at the first hearing. Cranstons provided insurance information to the court at the second hearing. The question is whether Cranstons had notice which appears in the record of the court’s intent to convert the motion to one for summary judgment.
The court’s statements in the colloquy reprinted above were sufficiently ambiguous that they did not satisfy the notice requirement. Also, although Cranstons presented the court with their own materials outside the pleadings, the trial court never ruled on Cranstons’ objection to conversion. Furthermore, its orders were captioned and worded as orders to dismiss rather than orders for summary judgment. Because the requirement of clear, unambiguous notice for conversion was not satisfied, we will treat the court’s orders in this case as orders to dismiss rather than as converted orders for summary judgment.
We set forth concisely our standard of review of a trial court’s order dismissing a complaint:
According to our standard of review we will sustain a dismissal of a complaint only if it shows on its face that the plaintiff was not entitled to relief under any set of facts. In considering such a motion, the “facts alleged in the com[255]*255plaint are admitted and the allegations must be viewed in the light most favorable to plaintiffs.” Dismissal is a drastic remedy, and is sparingly granted.
Matter of Paternity of JRW, 814 P.2d 1256, 1259 (Wyo.1991) (quoting Mostert v. CBL & Associates, 741 P.2d 1090, 1092 (Wyo.1987)) (citations omitted).
DISCUSSION
In Cranstons' first two issues, they argue alternatively that either WCWPB is not a separate governmental entity entitled to notice of claim under the Wyoming Governmental Claims Act, or that WCWPB is estopped from asserting that it is a separate governmental entity.
Governmental entities and their public employees in Wyoming are immune from tort liability, except as provided for in W.S. 1-39-101 et seq. (June 1988 Repl.) (Wyoming Governmental Claims Act). See W.S. l-39-104(a). Actions against governmental entities may only be pursued if brought in procedural and substantive compliance with the act. See Boehm v. Cody Country Chamber of Commerce, 748 P.2d 704, 708-09 (Wyo.1987). One such procedural requirement is that claimants give notice of their claim to the governmental entity in order to maintain an action under the act: “No action shall be brought under this act against a governmental entity unless the claim upon which the action is based is presented to the entity as an itemized statement in writing within two (2) years of the date of the alleged act, error or omission * * W.S. 1-39-113.
Failure to give notice within the two-year claim period of a claim which falls under the statute acts as an absolute bar to suit. Duran v. Board of County Commissioners of Sweetwater County, 787 P.2d 971, 972-73 (Wyo.1990) and cases cited therein. A litigant’s failure to file a timely claim deprives the district court of subject matter jurisdiction. Dee v. Laramie County, 666 P.2d 957 (Wyo.1983).
It is undisputed in this case that Cranstons did not present a separate notice of claim to WCWPB within the two-year claim period. The only notice given was the certified letter mailed to the Commissioners. Cranstons argue, however, that this notice to the Commissioners gave sufficient notice to WCWPB of their claim because WCWPB is not a separate “governmental entity” from Weston County.
Cranstons make several arguments as to why the WCWPB should not be considered a separate governmental entity. First, they note that it is not included within any of the enumerated categories in W.S. 1-39-103 (June 1988 Repl.). For purposes of the Governmental Claims Act, governmental entity “means the state, University of Wyoming or any local government.” W.S. 1-39-103(a)(i). Local government “means cities and towns, counties, school districts, joint powers boards, airport boards, public corporations, community college districts, special districts and their governing bodies, all political subdivisions of the state, and their agencies, instrumentalities and institutions.” W.S. l-39-103(a)(ii) (emphasis added).
Cranstons argue that since weed and pest control districts are not included as a separate entity in the definition of “local government,” the legislature recognized them as a part of county government for purposes of the statute. However, we believe that the WCWPB is included in this statute as a “special district [or its] governing body.” Accordingly, Cranstons’ first argument fails as a matter of law.
Cranstons next argue that WCWPB is not a separate entity because it cannot operate without the authority of the county commissioners. Cranstons note that the Commissioners appoint the board members for WCWPB and that WCWPB cannot set its own budget or raise taxes on its own to fund itself. Cranstons conclude that WCWPB is the same governmental entity as Weston County. Our examination of the pertinent statutes relating to weed and pest control boards leads us to the opposite conclusion.
WCWPB is a county weed and pest control district created under the auspices of the Wyoming Weed and Pest Control Act of 1973, 1973 Wyo.Sess.L. ch. 30 § 1. This [256]*256act is found within our statutes, W.S. 11-5-101 et seq. (June 1989 Repl.). Under the act, all land within the boundaries of Wyoming is included in weed and pest control districts whose boundaries are coexistent with the county in which the district is located. W.S. 11-5-103. Each weed and pest control district is operated by a district board. W.S. 11-5-105. The board members are appointed by the county commissioners of each district from a list of nominations submitted by local landowners. W.S. ll-5-104(a). County commissioners have the power to remove a director for “repeated unexcused failure to attend meetings or for refusal or incapacity to act as a district board member.” W.S. 11-5-104(e).
County commissioners are directed to levy an annual tax to carry out the act. This tax, which is levied on all property in the district and cannot exceed one mill on each dollar of assessed value, is specifically defined as “not part of the general county or city mill levies.” W.S. 11-5-111. Any funds appropriated by the legislature for weed and pest control are allocated by an allocation committee which consists of the Commissioner of Agriculture, three members appointed by the state weed and pest council, and one member of the Wyoming Board of Agriculture. W.S. ll-5-113(a).
The above statutes indicate that weed and pest control boards are separate entities from the counties in which they are located. Although the county commissioners appoint members to the board, their appointment and removal powers are limited. They can only appoint from a list of persons nominated by local landowners, and they can only remove board members for failure or incapacity to carry out their duties. Furthermore, although the county commissioners levy the tax and set the amount which is to be levied for the board, the tax itself is separate from city or county levies. Any legislative appropriations are allocated by the allocation committee without the need to seek the county commissioners’ authorization.
W.S. ll-5-105(b) enumerates the powers of local weed and pest districts. The deciding factor for us is the authorization for local districts to “sue and be sued.” W.S. ll-5-105(b)(i). If a district is given statutory authority to be sued in its own name, it seems only logical that it is a separate governmental entity and, absent evidence to the contrary, it is entitled to notice under the Governmental Claims Act.1 Our review of statutory authority convinces us to hold that a weed and pest control district under Title 11 is an independent governmental entity for purposes of the Governmental Claims Act.
Cranstons next argue that WCWPB is estopped in this case from claiming that it is a separate governmental entity. They rely on the elements of estoppel from a statute of limitations set forth in Taylor v. Estate of Taylor, 719 P.2d 234, 240 (Wyo.1986): “The delay in filing the action must be induced by the defendant; the defendant must have misled the plaintiff; and the plaintiff must have acted on the misinformation in good faith to the extent that he failed to pursue his action in a timely manner.”
Cranstons argue that WCWPB had actual notice of the claim against it prior to the expiration of the two-year claim period, that WCWPB led Cranstons to believe that it had notice, and that they relied on this belief in good faith in not filing their claim with WCWPB. They point to several elements in the record which they claim support this contention. First, a letter from an insurance analyst concerning coverage dated October 25, 1988, states that WCWPB was consulted regarding the claim. Second, the county attorney represented both appellees throughout the case. Third, the DEQ served WCWPB with a Notice of Violation which described the harm which is the subject of this case.
While these elements certainly establish that WCWPB had notice during the claims period that Cranstons thought they had a claim against WCWPB, they do not show that the delay in filing was induced by [257]*257WCWPB, or that WCWPB misled them as to the need to file a claim. This court has addressed a similar estoppel argument in Duran:
Duran [appellant] relies upon the mere pendency of negotiations as the basis for employing the doctrine of estoppel, both in her brief in this court and in her defense to the motion to dismiss in the district court. Such an assertion is not of itself sufficient to establish an estop-pel. * * * There was no assertion of representation by the insurer relied upon by appellant. As a matter of law, what is asserted is insufficient to require that the issue be presented to a fact finder.
Duran, 787 P.2d at 974-75 (citations omitted). In this case, the representations which Cranstons bring to our attention are insufficient as a matter of law to establish that WCWPB misled them or that the delay in filing was due to WCWPB’s actions. Our review of the complaint in the light most favorable to Cranstons demonstrates that there is no set of facts alleged which, if proved, could establish the last two elements of an estoppel claim here.
Cranstons’ third issue is whether they substantially complied with the notice provision of the Governmental Claims Act by sending the notice of claim to the Commissioners. Cranstons argue that since WCWPB had actual notice of their claim within the two-year statutory period, the purpose of the notice provision was served.
Generally, service of a notice of claim on one governmental entity is not sufficient to give notice to other potential defendants. Cf. Davis v. City of Casper, 710 P.2d 827 (Wyo.1985) (notice of claim sent to City of Casper but not Natrona County; dismissal upheld as to County for failure to send notice of claim). In this case, however, Cranstons assert that since both entities had the same attorney, and there is evidence that WCWPB had actual notice of the claim, the notice sent to Weston County substantially complied with the statute.
Cranstons cite Rissler and McMurry Company v. Wyoming Highway Department, 582 P.2d 583 (Wyo.1978), a case in which we allowed the plaintiff to assert substantial compliance with a notice of claims statute. In Rissler, the plaintiff submitted a claim to the Highway Department in compliance with a departmental regulation and then negotiated with the Highway Department until after the deadline for filing notice of claim with the state auditor had passed.2 We held that the purposes of the claims statute, timely notice to the state of claims against it, had been fulfilled by notice of claim to the Highway Department, particularly since plaintiffs claim had opened the way for settlement negotiations between the parties.
We distinguish Rissler from this case, however. In Rissler, the plaintiff sent a claim to a governmental entity whose published claims procedure contained an independent notice requirement. In this case, there was no such independent procedure on which Cranstons erroneously relied. Also in Rissler, the Highway Department entered into negotiations with the plaintiff, which suggested to the plaintiff that it was following the appropriate claims procedure. Here, no such negotiations were entered into between Cranstons and WCWPB. There is simply no consequent “gamesmanship” or bad faith by the governmental entity here such as the Rissler decision sought to avoid. Rissler, at 586.
Furthermore, that WCWPB and Weston County shared the same attorney and WCWPB had actual notice of Cranstons’ claim do not, in and of themselves, excuse compliance with the notice provision of the statute. WCWPB had a right to rely on Cranstons’ compliance with the statute, particularly in view of the cases cited above which state that compliance is jurisdictional. WCWPB could not be said to be on official notice of the claim until Cranstons filed such notice as prescribed. We will not excuse strict compliance with the procedural norms of the Governmental Claims Act except in compelling circumstances. We hold that Cranstons did not substantial[258]*258ly comply with the Governmental Claims Act claim procedure as to their claim against WCWPB. We affirm the trial court’s dismissal as to WCWPB for Cran-stons’ failure to send proper notice under W.S. 1-39-113.
Cranstons’ final two arguments relate to their claim against Weston County. We will consider their last argument first, in order to discuss the arguments in logical order. Thus, we first consider whether the County owed them a duty of care.
Cranstons argued in their amended complaint that the Commissioners were negligent in their hiring of the WCWPB board members and in failing to properly supervise WCWPB’s actions. The trial court determined that the Commissioners did not owe a legal duty of care to Cranstons for the injuries stated. It dismissed their amended complaint for failure to state a claim.
We agree that Cranstons’ amended complaint does not state a claim for negligent supervision. The Commissioners had no duty to supervise WCWPB or its employees under the applicable statutes. However, we hold that their amended complaint does state a claim under the theory of negligent hiring.
We have found no published Wyoming case which sets out the elements of a claim by a nonemployee third party for negligent hiring. This tort was presented to the court in Blake v. Rupe, 651 P.2d 1096, 1103 (Wyo.1982), cert. denied, 459 U.S. 1208, 103 S.Ct. 1199, 75 L.Ed.2d 442 (1983), but the case was resolved on other grounds. We accept the special definition of this cause of action set forth in Restatement (Second) of Agency § 213 (1958):
A person conducting an activity through servants or other agents is subject to liability for harm resulting from his conduct if he is negligent or reckless:
* * # * * *
(b) in the employment of improper persons or instrumentalities in work involving the risk of harm to others.
In this case, the Commissioners were not “conducting an activity through servants or other agents” when herbicide was applied to the state land. The employees who did the application were employees of WCWPB, not of the Commissioners. However, only the Commissioners had the statutory power to appoint the board members who actually did the supervising. That statutory power carried with it a duty not to negligently hire board members. Therefore, a jury could reasonably find that the Commissioners’ failure to properly appoint board members was the proximate cause of Cranstons’ injuries. See Stephenson v. Pacific Power and Light Co., 779 P.2d 1169, 1178 (Wyo.1989); McLaughlin v. Michelin Tire Corp., 778 P.2d 59, 87 (Wyo.1989) (Urbigkit, J., specially concurring and dissenting); McClellan v. Tottenhoff, 666 P.2d 408, 414 (Wyo.1983) (proximate cause is a question of fact for the jury unless reasonable minds could not disagree.).
Appellee Commissioners argue that since the statute requires them to select board members from a list of nominated candidates, and since they can only remove board members for neglect of their duties, not incompetence, they cannot be held responsible for negligently choosing board members. See W.S. 11-5-104. These contentions, if supported by appropriate facts in this case, might justify the entry of summary judgment. However, at this stage of the proceedings there are still conceivable sets of facts under which Cran-stons could establish their claim: if, for example, there were far more applicants for the board than positions and the Commissioners negligently failed to properly screen the applicants. Under the circumstances, we cannot uphold the order dismissing Cranstons’ amended complaint, because there are factual circumstances in which they could conceivably be entitled to recover on their claim.
In sum, we hold that Cranstons’ amended complaint states a claim for negligent appointment of the board members by the Commissioners. On remand Cranstons will have the burden of establishing that the Commissioners were negligent in appointing the board members, that the board [259]*259members or their servants negligently caused their appellants’ injuries, and that the failure to properly appoint the board member was the proximate cause of their injuries.
We next consider Cranstons’ argument that the Commissioners waived their immunity to liability by purchasing liability insurance. W.S. 1 — 39—118(b)(i) provides that a governmental entity may extend its liability by purchasing insurance: “If a governmental entity has insurance coverage either exceeding the limits of liability as stated in this section or covering liability which is not authorized by this act, the governmental entity’s liability is extended to the coverage.”
The trial court in this case found that there was insufficient proof to establish that the county had liability insurance which would have indemnified the Commissioners against the Cranstons’ injuries and thereby waive immunity under the Governmental Claims Act. However, in considering the motion to dismiss, the trial court should have made its findings based solely on the allegations of the amended complaint. The only question about insurance coverage at the dismissal stage was whether the Cranstons pled it and thereby avoided Rule 12(b) dismissal on the basis of sovereign immunity. If the complaint pled applicable insurance coverage, it should not have been dismissed on its face. The record shows that the amended complaint did plead applicable liability insurance:
“14. Defendant COUNTY has had insurance coverage in effect for the period of time covered in this Complaint which is 1974 through the present, and are [sic] therefore liable to the extent of said insurance coverage.”
Since dismissal is inappropriate, we reverse and remand as to the complaint against Weston County to allow development of the record concerning insurance coverage. The trial court should see to it that the record is more fully developed, if necessary, before taking further action on the insurance issue. See Pickle v. Board of County Commissioners of Platte County, 764 P.2d 262, 266 (Wyo.1988).