{"data":{"id":"us/40-cfr-141.552","jurisdiction":"us","citation":"40 CFR 141.552","heading":"My system consists of “alternative filtration” and is required to conduct a demonstration—what is required of my system and how does the State establish my turbidity limits?","body":"(a) If your system consists of alternative filtration(filtration other than slow sand filtration, diatomaceous earth filtration, conventional filtration, or direct filtration) you are required to conduct a demonstration (see tables in § 141.551). Your system must demonstrate to the State, using pilot plant studies or other means, that your system's filtration, in combination with disinfection treatment, consistently achieves:\n(1) 99 percent removal of Cryptosporidium oocysts;\n(2) 99.9 percent removal and/or inactivation of Giardia lamblia cysts; and\n(3) 99.99 percent removal and/or inactivation of viruses.\n(b) [Reserved]","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER D—WATER PROGRAMS","PART 141—NATIONAL PRIMARY DRINKING WATER REGULATIONS","Subpart T—Enhanced Filtration and Disinfection—Systems Serving Fewer Than 10,000 People"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"d8153737188fb638e77af645eca623cd918fad15f762afd88a55a13aa4507fd6","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-141.551","next":"us/40-cfr-141.553"},"notice":"GroundRules: Original legal text. Not legal advice."}