An analytical method for total heavy metal complexing agents in water and its application to water quality studies

The principle research accomplishment on this project was the development of several methods of analysis for low levels of complexing agents, particularly chelating agents. These species are very important in water quality. It is only very recently that their importance has become very apparent in areas such as heavy metal transport, algal growth, and toxicity of heavy metals. The first method developed, was an atomic absorption analysis of strong heavy metal chelating agents. This method is based upon the fact that when copper ion is added to a water sample and the pH adjusted to 10, the only copper that remains in solution is that which is in a complexed or chelated form. The precipitate which comes out of the solution at pH 10 contains the copper which is not complexed or chelated and is removed by filtration. The copper remaining in solution is measured by atomic absorption. This copper concentration is a measure of the amount of chelating agent in the water and is called the copper equivalent chelating capacity of the water. The method was used on a number of natural water samples. It was found, for example, that normal creek water contains about one milligram per liter copper equivalent chelating capacity. Water supporting algal growth typically contains about the same level. Raw sewage from a nonindustrial source typically contains around 3 milligrams per liter copper equivalent chelating capacity, whereas properly treated sewage effluent contains 1 milligram per liter or less. The method was extended to the analysis of cyanide ion, a water pollutant found in mining and metal processing effluents. It is applicable to cyanide and provides a simple and convenient method for the analysis of this pollutant. In the final few weeks of the project, a new method was developed in which the copper is solublized from a copper-containing chelating ion exchange resin. This method is much more rapid than the first method described, though somewhat more subject to interferences. It is applicable to automated procedures and as a detection system for chelating agents separated by liquid chromatography. It is extremely sensitive and can detect as little as 5x10^-7 millimoles of NTA. These applications of the method are being pursued under a USDI-OWRR matching grant starting on July 1, 1973.Project # A-056-MO Agreement # 14-31-0001-382

Recent Sediments of the Central California Continental Shelf, Pillar Point to Pigeon Point: Part A -- Introduction and Grain Size Analysis

The following work is part of a continuing study of the sediments and sedimentary processes of the continental shelf of central California done in cooperation between the University of California, Berkeley and the Coastal Engineering Research Center, U.S. Army Corps of Engineers. Sediment analyses of the samples were done at the University of California, Berkeley, utilizing the facilities of the Departments of Civil Engineering, and Geology, and the Institute of Marine Resources. The results of this study will be presented in three separate reports:Part A Part B Part C Introduction and Grain Size Data (this volume) Mineralogical Data Interpretation and Summary of Results.The first two reports, Parts A and B, raw data will be presented with little or no interpretation. In Part C the authors' interpretation of the data plus background information and previous work in the study area will be given