Excerpt from A Monitoring Plan for the Occurrence of Hydrocarbon Constituents in Lakes Powell, Mead, and Mohave, Arizona, Nevada, and Utah The overall purpose of this monitoring plan is to present a sampling and analysis approach that will provide the nps with representative data on the occurrence of hydrocarbon compounds in waters of Lakes Powell, Mead, and Mohave within Glen Canyon nra and Lake Mead nra. The monitoring plan identifies locations for collecting samples, frequencies of sample collection, affected sampling media, and target constituent compounds.