(concurring in part, dissenting in part)—I concur with the majority's decision to reverse and remand this action. However, I disagree with the majority's holding that an easement "for railroad purposes" does not, as a matter of law, include a hiking and biking trail or other arguably "recreational" use. I believe that any discussion of what is intended by "railroad purposes" is premature in this instance.
*462This case entails the interpretation of a grant of an interest in land which, for purposes of the defendants' CR 12(b)(6) motion, is considered an easement. The scope of an easement is controlled by the intent of the parties at the creation of the easement. Brown v. Voss, 105 Wn.2d 366, 371, 715 P.2d 514 (1986); Zobrist v. Culp, 95 Wn.2d 556, 560, 627 P.2d 1308 (1981); Logan v. Brodrick, 29 Wn. App. 796, 631 P.2d 429 (1981). Regardless of what general rules might apply to easements for railroads, a court must always look to the particular language of the deed in question to determine intent. State v. Department of Natural Resources, 329 N.W.2d 543, 546 (Minn.), cert. denied, 463 U.S. 1209 (1983). When the deed is ambiguous on the question of intent, the court then may look to extrinsic evidence of the circumstances surrounding the conveyance. Roeder Co. v. Burlington Northern, Inc., 105 Wn.2d 269, 273-74, 714 P.2d 1170 (1986). When extrinsic evidence is considered, the interpretation of the conveyance becomes a mixed question of fact and law; the question of intent, however, is a factual one. Roeder Co. v. Burlington Northern, Inc., 105 Wn.2d 567, 571-72, 716 P.2d 855 (1986).
The deeds at issue here are ambiguous on the question of intent. The deeds themselves do not mention "railroad purposes" but speak instead of "benefits and advantages” accruing to the grantors. Clerk's Papers, at 69-70. What these "benefits and advantages" are is not unambiguously evident from the face of the conveying instruments. Thus, identifying the benefits and advantages and deciding whether they could reasonably ensue from the use of the easement as a hiking and biking trail or recreational use is a factual determination to be made by the trial court.
This case came before the Supreme Court on appeal of a CR 12(b)(6) dismissal of the plaintiffs' claims. Arguably the 12(b)(6) motion was converted into a motion for summary judgment when the trial court considered matters outside the pleadings. See CR 12(c). In any event, the defendants in their 12(b)(6) motion have not conceded that the conveyances were intended as easements for railroad purposes *463nor has the trial court made findings in that regard. Because the parties clearly dispute the nature and extent of the interest conveyed—a dispute that is partly factual—the case belongs in trial.
The trial court's inquiry should follow basic principles of deed interpretation. If the conveyances are found to be easements, the court should consider not only the specific intentions of the original parties to the grant, but also "the nature and situation of the properties subject to the easement, and the manner in which the easement has been used and occupied." (Citation omitted.) Logan v. Brodrick, supra at 799. When an easement is intended for a specific use or purpose, an invalid use or purpose will violate the easement, even when the new use or purpose creates no additional burden on the servient estate. See Brown v. Voss, supra at 372.
The fact that the original parties' intent circumscribes the scope of an easement does not mean that any variation from the original use and burden violates the easement.
The law assumes parties to an easement contemplated a normal development under conditions which may be different from those existing at the time of the grant. Normal changes in the manner of use and resulting needs will not, without adequate showing, constitute an unreasonable deviation from the original grant of the easement.
(Citations omitted.) Logan, at 800; see also Natural Resources, at 547 (easements are not limited to particular methods of use in vogue at time of conveyance); 25 Am. Jur. 2d Easements and Licenses §§ 74, 77 (1966) (when easements are in general terms without limitations, grantee or grantee's successors in interest are permitted "unlimited reasonable use"). Cf. 5 Restatement of Property § 484 (1944) ("In ascertaining, in the case of an easement appurtenant created by conveyance, whether additional or different uses of the servient tenement required by changes in the character of the use of the dominant tenement are permitted, the interpreter is warranted in assuming that the *464parties to the conveyance contemplated a normal development of the use of the dominant tenement."). The reasonable use of an easement is a factual determination. 25 Am. Jur. 2d supra, § 74.
An easement for a railroad, then, may in some cases allow for a change in the type of vehicle used or the frequency of use. See Natural Resources, at 546-47; 25 Am. Jur. 2d, supra, § 74. At the same time, however, "[a] principle which underlies the use of all easements is that the owner of the easement cannot materially increase the burden of the servient estate or impose thereon a new and additional burden." 25 Am. Jur. 2d, supra, § 72. One could assume the grantor would never have made the conveyance if the burden on the servient estate would have been too great. Arguably, an easement "for railroad purposes" could be abused by a volume or frequency even of railroad traffic when that traffic is far in excess of the grantor's reasonable expectations.
In sum, the task before the trial court is to ascertain the original parties' intent with respect to the burdens they assumed and the "benefits and advantages" they anticipated. The court must look not only at the circumstances existing at the time of the grant but also at the circumstances the parties reasonably expected would develop. If the deeds are construed as requiring a particular purpose or use, the court must ascertain the natural development of that purpose or use. If the court finds that current or prospective purpose or use follows the natural and reasonable development of the estate, the court then must satisfy itself that the resulting burden on the servient estate is not materially increased. In making these factual determinations, the court should consider the nature and situation of the properties in question and the nature of the original and changed uses. See Logan, at 799; see also 25 Am. Jur. 2d, supra, § 74.