On February 22, 2001, EPA issued an AO to Respondent (PRASA) for failure to comply with the filtration requirements of the SDWA. The AO required the Respondent to filter the Cedrito public water system by November 15, 2002 and placed Respondent on an enforceable schedule. On November 7, 2002, EPA issued a Complaint and Notice of Porposed Assessment of a Civil Penalty and Notice of Opporturnity to Request a Hearing.