…er liter Water None None None > 35 microns None None USGS use and no use by EPA 32279 Pheophytin a >35u, calcd ug/l BIO Pheophytin a greater than 35 microns, calculated as pheophytin a (P32213) less pheophytin a <35 um (P32273), micrograms per liter Water None None None > 35 micr…