SITE INFORMATION AND CORRESPONDENCE 1980-1999

Home Browse Search

State Board Order reiterates that basic equation, stating: "In order to comply with the federal antidegradation,the mass loading limits should also be revised,based on mean loading, concurrently with adoption of revised effluent limits." Order at 78. Hence, if the current permit is not proposing mass limits based on the current "mean loading",the permits will be in violation of the antidegradation policy and the State Board's previous Order. See also EPA Technical Support Document for Water Quality-Based Toxics Control at 110 (§ 5.7.1). To comply with antidegradation policy,mass limits must be included in the permit consistent with the State Board guidance. Required mass limits include mercury,pesticides,electrical conductivity,toxicity (both acute and chronic), zinc,lead,cyanide,Bis (2-ethylhexyl)phtahalate and chlorine. III. THE TURBIDITY RECEIVING WATER LIMIT AND THE TOTAL SUSPENDED SOLIDS EFFLUENT LIMIT BACKSLIDES FROM THE PREVIOUS PERMIT. Receiving Water Limitation 7, in order number 93-030, states that the discharge shall not cause in the receiving water [t]urbidity to increase more than 10 percent over background levels." The Receiving Water Limitation in the Tentative Permit states that the discharge shall not cause [t]urbidity to increase more than 20 percent of background levels." The turbidity limit in the Tentative Permit backslides from the previous permit and may not comply with the turbidity standard in the Basin Plan. This is particularly important given the low dissolved oxygen problems in Dredger and Bishop Cuts and White Slough. These waterways are highly eutrophic containing high levels of algae. Any reduction in light penetrating the water will cause algae to die and decompose thereby increasing oxygen demand. The turbidity limit must be strengthened not relaxed. The Discharger's previous permit limited Suspended Matter to 50 mg/1 as a Daily Maximum. The Tentative Permit proposes a Daily Maximum of 90 mg/l of Suspended Solids which would backslide from the previous permit. IV. THE PROPOSED COL]FORM LIMIT IS INADEQUATE TO PROTECT HUMAN HEALTH. Effluent limits in the Tentative Permit's Effluent state that effective 1 May 2004, a new discharge effluent limitation for total coliform organisms of 2.2 MPN/100 ml,monthly median, and 23 MPN/100 ml,daily maximum, shall be applied. However, the California Department of Health Services (DHS)has been very explicit that a 30 day median will not protect contact recreation. For example,in their comments on the El Dorado Irrigation District Deer Creek Wastewater Treatment DeltaKeeper,Tentative NPDES Permit,Lodi, 17 December 1999,Page 7.