Under the Safe Drinking Water Act (SDWA), EPA promulgates national primary drinking water regulations (NPDWRs) that specify maximum contaminant levels or treatment techniques for drinking water contaminants. The NPDWRs include analytical testing methods used to measure compliance. Under the SDWA Section 1401(1)(D), NPDWRs include “criteria and procedures to assure a supply of drinking water which dependably complies with such maximum contaminant levels; including accepted methods for quality control and testing procedures . . . ” EPA can promulgate national secondary drinking water regulations that primarily affect the aesthetic qualities of drinking water. These regulations are not federally enforceable, but are used by the states as guidelines. The secondary regulations include analytical techniques.