In Voices for Rural Living v. El Dorado Irrigation Dist. (2012) 209 Cal.App.4th 1096, 1107 147 Cal. Rptr. 3d 480 (Voices), this court said two questions are at issue in reviewing an agency's determination that a project did not trigger the exception for unusual circumstances that have a significant effect on the environment. "'First, we inquire whether the project presents unusual circumstances. Second, we inquire whether there is a reasonable possibility of a significant effect on the environment due to the unusual circumstances. '" (Voices, supra, 209 Cal.App.4th at pp. 1107-1108, quoting Banker's Hill, Hillcrest, Park West Community Preservation Group v. City of San Diego (2006) 139 Cal.App.4th 249, 278 42 Cal. Rptr. 3d 537 (Banker's Hill).) "'A negative answer to either question means the exception does not apply.'" (Banker's Hill, supra, 139 Cal.App.4th at p. 278.) "The first question, whether the project for which a categorical exemption is being claimed involves unusual circumstances, is an issue of law we review de novo. " (Voices, supra, 209 Cal.App.4th at p. 1108, italics added.) The Court held that the unusual circumstances exception applied to an irrigation district's agreement to provide water to a tribal casino and hotel project. (Voices, supra, 209 Cal.App.4th at pp. 1108-1114.) The project involved relocating the existing three-inch water meter and installing a short section of pipeline linking the meter to an existing water main, both of which would occur on tribal land. (Id. at p. 1103.) The district determined the project was exempt under the Class 3 categorical exemption for new construction or conversion of small structures. (209 Cal.App.4th at p. 1104.) The Court concluded, "the MOU (memorandum of understanding) project presents circumstances that are unusual for this categorical exemption. The proposed project's scope, providing 216 additional EDU's (equivalent dwelling units) of water to a casino and hotel project so large it brings with it its own freeway interchange instead of providing one or four EDU's of water as contemplated by the class 3 categorical exemption is an unusual circumstance under that exemption. The sheer amount of water to be conveyed under the MOU obviously is a fact that distinguishes the project from the types of projects contemplated by the class 3 categorical exemption." (Id. at p. 1109.)