Waste Management

1. Waste Management A Brief History of Waste Disposal: The Early Years: “Dilute and Disperse” -Waste production was taken care of by dumping, either into unused land areas (“swamps”) or into rivers. Many cities have areas that once were “dumps”, and are now covered by parks or buildings.

3. Most trash or waste was either buried loose, or in barrels. Big Problem: Early trash dumps were used for everything, and unregulated. Many toxins were dumped with no thought as to the repercussions. In Delaware, several sites that were formerly sand and gravel pits were used as dumps. EX: Army Creek Landfill, Tybouts Corner Landfill, Delaware Sand and Gravel Landfill

4. Most of these dumps were “open pit” dumps, with no effort made to cover up the trash and waste. In some instances, the waste was periodically burned, to provide more space. Sanitary Landfills Later designs were not open pit, because the waste was covered with a layer of soil. Landfills today use this method of covering the trash. The layer of soil prevents access to the waste by birds, insects and rodents.

5. Sanitary Landfills have distinct alternating layers of compacted trash and soil. Soil Layer Layer of Compacted Trash

6. Problems Associated with Landfills 1) Landfill space is very limited Ex: Philadelphia is out of landfill space (it used to be near the airport), and now has to ship its trash elsewhere (very costly!) In Delaware:The Cherry Island Landfill is near capacity, and studies are underway to determine if the hill of trash can be made even higher. Understandably, people living near the landfill are quite upset about the prospects of more trash.

7. 2) Creating newer, safer landfills is an uphill battle. NIMBY Syndrome The sites chosen for landfills often are located near poor, politically disconnected populations. 3) Leachate from the Landfill Probably the biggest environmental problem with landfills, leachate is the movement of water through the waste, into the groundwater or a nearby body of water.

8. The nature of the leachate depends on the nature of the waste,the quantity of water, and the time it takes to percolate through the pile. 4) Atmospheric Pollution Since the waste is cut off from the air, it degrades anaerobically. Anaerobic degredation takes longer, and produces different products. Rather than decomposing into CO2, the trash decomposes into CH4, methane gas.

14. The Composition of Our Solid Waste Solid waste varies in composition depending on its source. Paper is the largest component of the waste stream, at about 38%. The single largest item is newspaper, which accounts for over 18% of solid waste.

15. The Composition Of the Solid Waste Stream

16. Waste Management, or “What Do We DO With All This Stuff”? Integrated Waste Management (IWM) “a set of management alternatives that include reuse, source reduction, recycling, composting, landfills, and incineration” • Reduce, Reuse, Recycle: the ultimate goal • of waste management is to reduce the amount • of waste that must be dealt with in the • first place.

17. Studies have indicated that waste could be reduced by as much as 70%. But HOW? -Reduction in packaging wastes -Reusable packages, deposits on containers -Packages made of easily recycled materials -Increased markets for recycled materials -Increased public support for recycling

18. 2) Composting Composting is a biochemical process that breaks down organic materials into rich soil-like material. It involves microscopic aerobic organisms, so the compost must be aerated to keep them alive. Piles of compost may be turned over periodically, allowing air to penetrate the pile. Large “digesters” continually turn the compost, making a very efficient system.

19. Problems with Composting: Compost having left over pesticides may kill plants that it is applied to. (herbicides) Compost can only be made when the organic material is collected separately from other trash. (plastics/metals, etc..) Composting does have a good future, because it can be done on a small scale, in yards and gardens.

20. 3) Sanitary Landfill (improved designs): Sanitary landfills are not going to be eliminated from any integrated system. There is always going to be a need for them. Improved designs will better handle leaching, and prevent contamination of air and groundwater. Landfills by design, not by accident, built to take specific types of waste. Built in monitoring systems, wells, liners, and leachate collection pipes.

21. An Idealized Sanitary Landfill

22. 4)Incineration: also known as “trash to steam”, has an advantage that the energy in the trash can be converted to heat energy. Also reduces the volume of trash up to 95%. Problems with Incineration -Creates air pollution, including SO2, NOx and all kinds of heavy metals (mercury, lead, etc…) -can be lowered with specialized equipment ($$) -The ash produced is very toxic, and needs to be handled as toxic waste.

23. Human Waste Disposal Since the dawn of human evolution, solid human waste has posed a problem as to its disposal. Wherever large populations of people lived, the waste became a big problem. For thousands of years in China and India, waste was used on crops as fertilizer. By the early 20th century, land application was taking place in many places, including the U.S. “Sewage Sludge”

24. Major Problems with Human Waste Disposal -Contamination with infectious agents, and their spread to waterways and treated crops Ex: Chi-Chi’s green onion problem (e-coli bacteria) -Pollution with heavy metals, industrial solvents, and pesticides. Industrial contributors could pre-treat their sewage, thereby eliminating many pollutants. ($$$) If the price of oil continues to climb, making man-made fertilizers more expensive,the use of human waste as fertilizer may gain favor again.

25. Ocean Dumping Types of things that get dumped into the oceans of the world: Dredge spoils: solid materials, generally silt,sand and pollutants dug up as navigation channels are deepened. Industrial wastes:acids, pesticide wastes, all matter of solvents, heavy metals Construction Debris Sewage Sludge Radioactive waste, explosives, garbage

26. Ocean Dumping Laws (U.S.) 1972: Ocean Dumping Act:Prohibited the dumping of chemical weapons, high level radioactive waste, biological warfare agents. 1988: Expanded to include sewage sludge, industrial waste, and medical waste. 1992: Provisions for a coastal water quality monitoring program were added

27. Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972 Permitted dumpingArticle 4 states that Contracting Parties "shall prohibit the dumping of any wastes or other matter with the exception of those listed in Annex 1." 1. Dredged material 2. Sewage sludge 3. Fish waste, or material resulting from industrial fish processing operations

28. 4. Vessels and platforms or other man-made structures at sea 5. Inert, inorganic geological material 6. Organic material of natural origin 7. Bulky items primarily comprising iron, steel, concrete and similar unharmful materials for which the concern is physical impact and limited to those circumstances, where such wastes are generated at locations, such as small islands with isolated communities, having no practicable access to disposal options other than dumping.

29. Hazardous Waste and its Disposal In the U.S., over 35,000 chemicals are classified as hazardous to the health of people or to ecosystems (Table 28.1 in textbook) The U.S. produces an average of 700 MILLION metric tons of hazardous waste annually. Most is generated by the chemical industry, followed closely by the electronics industry, and oil/petroleum industries.

30. Another great source of hazardous waste is US! Almost every household has used pesticides, oil, solvents, paints, batteries, etc. When these get thrown into the “regular” trash, they end up in a landfill not designed for hazmat, or, even worse, incinerated in a plant not made for burning hazmat. In the U.S., there are an estimated 2000 sites polluted with hazmat, and the number keeps going up as new sites are found.

31. Love Canal In 1976, toxic chemicals began oozing out of the soil covering what once had been a toxic dumping ground. Chemicals had been dumped by a company that produced pesticides, such as DDT, as well as lots of chlorinated solvents. The company sold the land to the city of Niagara, NY for $1 (it was pressured by the city to do so)

32. Homes and a school were eventually built over the buried waste. Studies in the late 70’s suggested high rates of cancer and birth defects among the residents of Love Canal, although results were debated. Efforts were made to clean and neutralize the site and the homes were eventually sold again to new owners. By 1990, $275 million had been spent on cleanup and relocation costs.

33. Hazmat Disposal There are several methods of dealing with hazmat disposal (Table 28.2 in textbook) • Secure Landfill: similar to a sanitary landfill, but • with more durable liners, closer inspection of • wells, etc. Secure landfills also usually have a leachate pond, which collects the liquid as it runs through the pile. The leachate is then sent to a treatment facility designed for hazmat.

34. Hazardous Waste Landfill

35. 2) Surface Impoundments: natural or man-made holes, in which liquid waste is held May include a plastic liner but not all do. Some rely on clay, rock or “impermeable soil”. Big Problems with Impoundments • They are open to the air, so evaporation takes • place, especially of solvents, etc.. 2) They can be flooded with heavy rain, and overflow into a nearby waterway or groundwater

36. 3) Deep Well Injection: drilled to a depth that is below any underground aquifers, and the liquid waste is injected under high pressure into the Earth. The well has to be sited so that it penetrates a permeable rock layer far underground, but is under an impermeable layer Well Impermeable Rock Porous Rock

37. Problems with Deep Well Disposal There have been instances where deep well injection has been implicated in causing earthquakes deep underground. The high pressure liquid lubricates rock layers, allowing them to slide. (Rocky Mtn. Arsenal, 1980’s) There is no guarantee that the waste will not find its way into a water system at some time. (no way to monitor the waste)

38. 4) Incineration Destruction by high temperatures Is considered a treatment, rather than disposal, because the leftover ash must still be disposed of in a landfill Is the chosen method for treatment of chemical weapon stocks (Johnston atoll) Also conducted on ships that are purpose built for incineration (very controversial)

39. Incinerators for hazmat are designed to reduce waste as much as is possible.

40. Hazardous Waste Legislation Ultimately, it would be far better to reduce the amount of waste, rather than dispose of or treat it. Resource Conservation and Recovery Act (RCRA): Identification of hazardous products and regulations regarding their disposal. “Cradle to Grave” regulation Promotes recycling, re-use of chemicals