AWWA JAW69599

To investigate the effect of hardness variabilityon implementation of the U.S. EnvironmentalProtection Agency's (USEPA's) hardness-dependentwater quality criteria (e.g., metals), theauthors superimposed effluent hardness and flowdata from two publicly owned treatment plantsonto 15 receiving water data sets. Althoughstudy results suggest that minimum effluenthardness may be used to develop protective effluentlimitations for chronic cadmium, copper,chromium (III), nickel, and zinc, the results alsosuggest that in some cases significant data arenecessary to develop protective effluent hardness-based limitations with 80% confidence.The study supports USEPA's recommendation thateffluent limitations for hardness-dependent metals bedeveloped with consideration for the dynamic conditionsseen in effluent and receiving water bodies. Theauthors provide guidance for implementing USEPA'shardness-based metals criteria based on real effluentand receiving water data sets. This generalized guidancewill help water managers and permitting officialsunderstand how to set metals limits that are protectiveof receiving water quality. Includes 6 references, tables, figures.

Product Details

Edition:

Vol. 101 - No. 2

Published:

02/01/2009

Number of Pages:

12

File Size:

1 file , 650 KB