HONOLULU, HAWAII, Dec. 4, 2012 -- The U.S. Environmental Protection Agency issued a notice of proposed action under the Clean Water Act to reissue National Pollutant Discharge Elimination System permits to the Guam Waterworks Authority for the Northern District and Agana Sewage Treatment Plants.
The proposed permits will require the plants to upgrade to full secondary treatment and establish wastewater quality levels consistent with secondary treatment requirements. GWA will need to comply with effluent limitations for bacteria based on protecting Guam's beaches, and establish additional controls to reduce sewage spills from the improper management of fats, oils and grease.
"GWA is currently under a schedule to make significant improvements to their drinking and wastewater infrastructure," said Jared Blumenfeld, EPA’s Regional Administrator for the Pacific Southwest."These new permits underscore EPA’s commitment to improve water quality for the protection of Guam’s ocean waters."
The Clean Water Act generally requires municipal wastewater treatment plants to use both primary and secondary treatment. The act does allow for variances from secondary treatment for marine discharges, provided the plant meets primary treatment requirements, water quality standards and other specific criteria. On Sept. 20, 2009, EPA issued final decisions to deny GWA’s application for variances. The EPA concluded discharges from the two plants no longer qualify because the treated wastewater exceeds Guam's ocean water quality standards for bacteria, designed to protect recreational activities such as swimming and fishing. Additionally, neither plant has met the minimum standards for primary treatment, which require 30 percent removal of total suspended solids and biochemical oxygen demand.
Primary treatment generally involves screening out large objects such as rags and sticks, removing grit, such as cinders, sand and small stones, and allowing wastewater to settle, followed by the removal of collected solids. When secondary treatment is used, primary-treated wastewater flows into another facility where a large portion of the organic matter in the wastewater is removed by treating the sewage with bacteria. There are a variety of different biological treatment techniques that allow the bacteria to consume most of the waste’s organic matter.
The proposed permits, fact sheets and background information are available on EPA's website for review and comment. EPA will consider all comments received on the proposed permit.
For more information, please visit: http://www.epa.gov/region09/water/npdes/pubnotices.html.
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