Chapter 1: Critical Evaluation of Cancer Risk from 2,4-D. Introduction, Epidemiological Evidence for Cancer Risk, Experimental Animal Studies, Evidence for Potential to Affect Cancer Risk, Environmental Fate and Potential for Human Exposure * Chapter 2: Ecotoxicological Risk Assessment for Roundup Herbicide. Introduction, Problem Formulation, Exposure Assessment, Toxicity Assessment, Risk Characterization, Uncertainty Analysis * Chapter 3: Manure and Wastewater Management for Cattle Feedlots. Introduction, Runoff from Cattle Feedlots, Manure Collection, Manure Storage and Processing, Air Quality and Feedlot Management, Managing the Feedlot Surface, Discussion.