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Management of Non-Point Source Pollution CE 296B Department of Civil Engineering California State University, Sacramento Lecture #11, March 12, 1998 Sources of Pollutants - Part VII Recall that we were looking at the six categories of pollutants: 1. Toxic inorganics - e.g. metals
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Management of Non-Point Source PollutionCE 296B Department of Civil Engineering California State University, Sacramento Lecture #11, March 12, 1998 Sources of Pollutants - Part VII
Recall that we were looking at the six categories of pollutants: 1. Toxic inorganics - e.g. metals 2. Synthetic organics - e.g. solvents 3. Biostimulants - BOD, nutrients 4. Sediment - clay, silt, sand, gravel Left off here 5. Pathogenic organisms - viruses, bacteria, protozoa 6. Trash - use your imagination
And the framework for acquiring knowledge about each category: • 1. What are the sub-categories in each category and what are representative members? and here • 2. What are the origins of pollutants? • 3. How pollutants are introduced to the flow stream? • 4. How pollutants behave in water?
Sample VI. The fifth category of pollutant to examine is pathogens. (cont.) E. Other methods for counting indicator organisms: 1. Membrane filters: Pour through a measured amount of sample or diluted sample Incubate 24 hours at 35°C, count colonies Membrane filter treated with lactose and a chemical that produces a green sheen when aldehyde is produced as part of the fermentation of lactose.
VI. The fifth category of pollutant to examine is pathogens. (cont.) • E. Other methods for counting indicator organisms:(cont.) 1. Membrane filters: Are the results, most probable numbers? 2. High tech methods: a. PCR (polymerase chain reaction) Looks for specific sequences of DNA, specific to the organism in question. In most techniques, the cells are first lysed. Problem with this method is that it picks up of the correct DNA, including DNA that is just floating around.
VI. The fifth category of pollutant to examine is pathogens. (cont.) • E. Other methods for counting indicator organisms:(cont.) • 2. High tech methods: (cont.) b. In situ hybridization. Does the PCR work inside the cell. Promising but needs to be better developed. c. Co-prostinal detection. Analyze for the fatty acid profile in fecal material of cholesterol digestion. There is a different profile for humans vs. different kinds of animals. Problem with this is very demanding analytical methods and inconclusive results.
VI. The fifth category of pollutant to examine is pathogens. (cont.) F. Origins of pathogens as pollutants: 1. Of course, improper disposal of fecal material. 2. Suggested sources of urban bacteria: • dogs • the homeless • soil 3. Suggested sources of rural bacteria: • poorly performing septic-leach field systems • animal husbandry • all the urban sources
VI. The fifth category of pollutant to examine is pathogens. (cont.) G. How do pathogens behave in water? 1. Many of the indicator bacteria reproduce. 2. The amount of dilution may be great. 3. Protozoa, a topic we have been glossing over, may indeed be a big problem. It does not require a large dose to make one sick. Protozoa may be quite persistent and are very hard to detect. This is a topic that will not go away or be dealt with soon.
Bacteria counts, indicator organisms such as total coliform or fecal coliform are astronomical. • VI. The fifth category of pollutant to examine is pathogens. (cont.) • G. How do pathogens behave in water? (cont.) 4. Recall an earlier diagram, a water body in an arid area during a storm event: Effluent, all storm water Receiving Water, all storm water
Discussion Break A major complaint from dischargers is that they are being held to an impossible standard on bacteria during storm events. Why do you think this is? What are some solutions? Problems with those solutions?
Discussion Break We have seen most all of the pollutants, their sources and potential impacts. Where would you rank pathogens in this scheme of things?
Recall that we were looking at the six categories of pollutants: 1. Toxic inorganics - e.g. metals 2. Synthetic organics - e.g. solvents 3. Biostimulants - BOD, nutrients 4. Sediment - clay, silt, sand, gravel 5. Pathogenic organisms - viruses, bacteria, protozoa 6. Trash - use your imagination on to here
And the framework for acquiring knowledge about each category: • 1. What are the sub-categories in each category and what are representative members? • 2. What are the origins of pollutants? • 3. How pollutants are introduced to the flow stream? • 4. How pollutants behave in water?
VII. The sixth category of pollutant to examine is trash. A. Not very exotic, but in urban areas, this can be a substantial problem. What are some examples of trash? 1. Litter - food containers, beer cans, etc. 2. Cigarette butts 3. Industrial material improperly disposed of. 4. Biomedical waste 5. Dead animals 6. Other ideas?
VII. The sixth category of pollutant to examine is trash. (cont.) B. What are the origins of trash? I know, a dumb question, my answer is improper disposal of discrete objects of human origin. C. How is trash introduced to the flow stream? A little more complicated, but not too much so. 1. Item is lying on the ground where the flow can push it to the receiving water.
VII. The sixth category of pollutant to examine is trash. (cont.) • C. How is trash introduced to the flow stream? (cont.) 2. Item(s) are directly deposited in the receiving water. Malicious littering. 3. If the item is large enough and/or dense enough, it will remain lodged in place until a large storm moves it downstream. Shock loading.
VII. The sixth category of pollutant to examine is trash. (cont.) D. How does trash behave in water? 1. The trash can sink to the bottom. From that location it can: • Impede navigation • Interfere with habitat • Decompose, either a biostimulant or release toxic compounds. • Something like biomedical waste can become a real health hazard.
VII. The sixth category of pollutant to examine is trash. (cont.) • D. How does trash behave in water? (cont.) 2. The trash can float on the surface. From that location it can: • Impede navigation • Interfere with habitat • Cause substantial damage to wildlife. The soft drink plastic rings issue as an example. • Interfere with aesthetics • Decompose, either a biostimulant or release toxic compounds.
VII. The sixth category of pollutant to examine is trash. (cont.) • D. How does trash behave in water? (cont.) 3. The trash can wash ashore. From that location it can: • Interfere with habitat • Cause substantial damage to wildlife. The soft drink plastic rings issue again. • Interfere with aesthetics • Decompose, either a biostimulant or release toxic compounds. • Something like biomedical waste can become a real health hazard.
Discussion Break The economic impact of trash as a non-point source pollutant can be very immediate. What are some examples of these economic impacts?
Discussion Break Some cynics, such as myself, believe that if the trash issue was solved, the interest in non-point source pollution would calm down. Do you agree? How would this reduced interest be a good thing? How would this reduced interest be a bad thing?
The End Of the Sources of Pollutants Section