Senior Associate, Hazen and Sawyer, Raleigh, NC
Principal Engineer, Hazen and Sawyer, Hollywood, FL
Professor, Trace Elements Research Laboratory, Texas A&M University, College Station, TX
Assistant Director of Utilities, City of Hollywood, Hollywood, FL
Pages: 12 Published: Jan 1997
Recent years have shown a trend by regulatory agencies towards increased scrutiny of metals in effluent discharges. As a result, stricter enforcement and lower water quality criteria for metals have become more commonplace. Additionally, EPA policy,adopted in May of 1995, promotes the use of dissolved metals to set and measure compliance with water quality standards and presents alternatives to metals permitting.Implementation of such criterion leaves no room for sampling and analysis error, thus putting a premium on obtaining accurate, low concentration trace metal data. At stake are potential noncompliance fines, unnecessary treatment plant modifications, hampering the industrial development of an area, loss of discharge permits, and exposure to increasingly common third-party lawsuits. The scientific and regulatory communities are now in general agreement that historical background receiving water metal concentrations are substantially overestimated (U.S. EPA 1992, Windom et al. 1991). It is therefore reasonable to assume that the same contamination has and is occurring with conventional sampling and analytical methods for effluents. Historically the total recoverable form of the metal was used for evaluation of environmental impact. Recently the EPA (U.S. EPA 1995, U.S. EPA 1994) has recommended the only way to obtain such accurate metal data at low concentrations is through the implementation of clean chemistry techniques. These techniques have been developed in the Oceanographic Community over the past twenty years out of the necessity to minimize contamination and analyze ambient trace metal concentrations which are very low (Bruland et al. 1979, Patterson and Settle 1976, Shiller and Boyle 1985 and 1987). Case studies involving a paper mill effluent copper study, an estuarine receiving water zinc study, and a Virginia municipal wastewater facility are examples of the application and importance of such techniques for the domestic and industrial community. Data are not only defensible to regulators, but provide a more accurate view of background and effluent concentrations. These results improve the integrity of the database and typically resolve the majority of concerns. However, if the metal concentrations are above levels of concern, various permitting alternatives such as the chemical translator approach, water effects ratios, recalculation of mixing zones,seasonally tiered permits or variances could be pursued. These alternatives focus on the toxic forms of the metals. This approach accommodates improved information and data to protect the environment, without diverting significant funds from other needs.
Metals Permitting, Clean Techniques, Water Effect Ratio, NPDES
Paper ID: STP12253S