letter fails to observe the formalities required by the Clean Water Act, the court lacks jurisdiction to hear the case. See Washington Trout v. McCain Foods, Inc., 45 F.3d 1351, 1355 (9th Cir.1995). Neither the regulation nor the Supreme Court has clearly established the specificity or level of detail that a notice letter must include. The regulation requires that the plaintiff provide enough information to permit the recipient to identify the dates of the violation, but does not specifically require the notice to contain those dates. See 40 C.F.R. § 135.5(a). Ideally, a plaintiff will identify a precise date, but if not, the range of the dates should be “reasonably limited.” California Sportfishing Protection Alliance v. City of West Sacramento, 905 F.Supp. 792, 799 (E.D.Cal.1995) (<HOLDING>). The Ninth Circuit has held that plaintiffs
holding that assertions of privilege must normally be raised as to each record sought and each question asked so that  the court can rule with specificity holding that a rule 10b5 claim must be stated with particularity holding that determining the existence a violation of  1692e when the statutory verification notice is contained in the letter turns on whether the specific text contains any impermissible overshadowing or contradiction with respect to the validation notice holding that dates of violation must be stated with some specificity and rejecting a notice letter that alleged hundreds of violations in a fiveyear range as insufficiently specific holding that the district court erred in finding violations that were not alleged specifically in the plaintiffs notice letter and no penalties could be imposed for those violations