Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Electrical Engineering


The Federal Environmental Protection Agency (EPA) strongly favors land application of sludge as a disposal method and requires communities to consider the application of sewage wastes to land as one of their alternatives to advanced wastewater treatment in order to be eligible for federal funding to improve sewage wastewater treatment facilities. Although use of sewage sludge on the land has definite benefits, several potential problems may develop when applying this method of disposal. One main concern has been the possibility of toxic metal pollution occurring in the application soils. If high concentrations of zinc, copper, lead, cadmium, etc. are present in the sludge, they may be retained by the soil and accumulate to levels which pose a health risk to the environment. To minimize risks from sludge application on land it is necessary to impose certain regulations and restrictions on sludge application rates and management techniques. EPA is primarily responsible for most of the regulations and guidelines applied to sludge disposal. Included in these guidelines is the requirement to analyze the sludge for any harmful or potentially toxic contaminants it may contain. Application soils should also be analyzed to establish a base reference before the addition of sludge and to determine any unusually high concentrations of elements that would restrict loading rates. This study was conducted to determine the trace metal concentrations in sewage sludge for the city of Brookings. S.D. Instrumental Neutron Activation Analysis (INAA) was used to determine the trace metal content since this methodology yields accurate, precise results for many elements at one time with a minimum of chemical and physical manipulation. Sludge samples were collected from the wastewater plant of Brookings as were soil samples from farming areas selected as potential sludge application sites. Standards and samples were irradiated in a TRIGA reactor at Washington State University. The gamma ray spectra were analyzed using a lithium drifted germanium crystal detector and a multichannel analyzer. Thirty-two different trace metals were identified and their concentrations determined for both sludge and soil.

Library of Congress Subject Headings

Sewage sludge as fertilizer -- South Dakota -- Brookings
Trace elements -- Analysis
Soils -- Trace element content
Nuclear activation analysis
South Dakota State University Theses



Number of Pages



South Dakota State University