The Environmental Protection Agency has opened another round of public comment on three key terms in a rule defining which bodies of water are subject to regulation, also known as the “Waters of the United States,” or WOTUS, rule, further lengthening the agency’s timeline for finalizing the rules.

The EPA and the Army Corps of Engineers announced on Friday that they would issue a supplemental notice seeking public input on additional options for defining “relatively permanent” and “continuous surface,” and including a new proposed definition for “perennial.”