PARENT SESSION
TP7 - Water Quality Criteria
Chair: Canton, Steve¹, ¹ Chadwick Ecological Consultants, Littleton, CO
2:10 PM to 5:30 PM - Tuesday, 19 November 2002
Room Ballroom A

(465) Storm Water Monitoring for Priority Toxic Pollutants in California.

Datta, Seema^*,1, Busalpa, Rodelia¹, Do, Luat¹, Young, Thomas¹, ¹ University of California, Davis, CA

ABSTRACT- The California Toxics Rule is a numeric water quality criteria for priority toxic pollutants to be applied to the waters in the State of California. The purpose of this study is to monitor storm water runoff so that the California Department of Transportation (Caltrans) may respond to and comply with requirements of the CTR. Two field sites, a highway site and a Caltrans maintenance yard, were monitored for metals and organic priority pollutants. Additionally, rainwater samples were collected alongside storm water in an effort to determine atmospheric versus highway contaminant loading. For in-situ monitoring of volatile and semi-volatile trace organic in storm water and rainwater, samples were collected by two modified ISCO auto samplers, and a customized rain sampler. A total of 110 organic compounds were grouped based on methods of collection and analysis into 5 categories: volatile organic compounds (VOCs), semi-volatiles (chlorinated pesticides, polychlorinated biphenyl, and polyaromatic hydrocarbons), nitrosamines, phenols, and others (phthalate esters, organic halogens, haloethers and miscellaneous). For the 2001-2002 rainy season, a total of 11 storm events were collected, and analyses have been determined for VOCs, nitrosamines and the phenolics groups. VOCs were not detected, however, 6 compounds were detected in all storm events in the nitrosamine and phenolic groups. Of these 6 compounds, pentachlorophenol and N-nitrosodiphenylamine were found to be in exceedance of the CTR criteria by one and two orders of magnitude, respectively. Storm water pentachlorophenol and N-nitrosodiphenylamine levels ranged from 0.5-4 ug/L and 19-550 ug/L, respectively. Pentachlorophenol has industrial application as a wood preservative while N-nitrosodiphenylamine is no longer manufactured in the United States for rubber products such as tires.

Key words: water quality, priority toxic pollutants, storm water , pentachlorophenol