TM94-03 Change in Method for Determining Chloride, Sulfate, and Fluoride

The National Water Quality Laboratory (NWQL) has had difficulty with determinations of chloride, sulfate, and fluoride at various times for different reasons over the past several years. In April 1990, three separate methods for these anions were replaced with a single ion chromatographic (IC) method (I-2057- 90) which used a Dionex OMNIPAX-500 column. Subsequently, problems arose with chloride using this method, and chloride was changed back to an approved photometric method on December 16, 1992 (see NWQL Tech Memo 93-03). Sulfate and fluoride continue to be determined with the OMNIPAX-500 column IC method.

Superseded by NWQL TM94-03