Hazardous Waste/ Bioremediation AP Environmental Science

Hazardous Waste Defined Hazardous waste is a waste with properties that make it dangerous or potentially harmful to human health or the environment.

Forms of Hazardous Waste Liquids Solids Contained gases Sludges. The EPA has a list of more than 500 specific hazardous wastes

Characteristics of Hazardous Contains one or more of 39 carcinogenic, mutagenic, or teratogenic compounds at levels that exceed established limits Ignitability – Create fires under certain conditions, are spontaneously combustible, or have a flash point less than 60 °C (140 °F). waste oils and used solvents. Corrosivity – Acids or bases (pH less than or equal to 2, or greater than or equal to 12.5) capable of corroding metal containers. Battery acid is an example.

Continued Reactivity – Unstable under "normal" conditions, can cause explosions, toxic fumes, gases, or vapors when heated, compressed, or mixed with water. lithium-sulfur batteries and explosives. Toxicity – Harmful or fatal when ingested or absorbed, this is the issue with leachate

Hazardous Landfill Construction

Hazardous Waste is Listed The F-list (non-specific source wastes). This list identifies wastes from common manufacturing and industrial processes, such as solvents that have been used in cleaning or degreasing operations. F-listed wastes are known as wastes from non-specific sources. The K-list (source-specific wastes). This list includes certain wastes from specific industries, such as petroleum refining or pesticide manufacturing. Certain sludges and wastewaters from treatment and production processes in these industries are examples of source-specific wastes.

Listed The P-list and the U-list (discarded commercial chemical products). These lists include specific commercial chemical products in an unused form. Some pesticides and some pharmaceutical products become hazardous waste when discarded.

When we have to pull in the little guys to help 2011 Bioremediation When we have to pull in the little guys to help 2011

Bioremediation the use of microbes to enhance the elimination of toxic compounds in the environment.

Strategies for bioremediation Using native (indigenous) microbes Improving microbes living conditions Adding selected microbes

Indigenous Microbes There are many naturally occurring microbes that occur in the environment that will decompose (eat) small amounts of toxin over long periods of time. This works at a very, very slow rate

Improving living condition People can add water and oxygen to the environment to speed up the growth rate of the microbes. Also by adding additional chemical such as fertilizers.

Adding more and different microbes Adding additional non-native microbes can help degrade the toxins Oil Spills

What microbes to use Toxins come in 2 categories Organic Inorganic The type of toxin determines how and what microbes can be used

Top 10 contaminants Lead Trichloroethylene Toulene Benzene PCB’s Chloroform Phenol Arsenic Cadmium Chromium

Anarerobic tolulene degrader Azoarcus tolulyticus (dividing in photo) Found in a gasoline contaminated aquifer Tolulene is one of the most toxic components of gasoline Important find because it is anaerobic and can work in an underground environment.

Using living organisms to breakdown organic compounds Biodegradation 2,4-D=Weed B Gone--Herbicides Oil PCB”s—insulator coolants in electric power plant transformers DDT—pesticide Plastic Detergents

2,4-D RoundUp,glyphosphate Three main microbes Alclegenes eutrohus Burkholderia cepia Halomonas 2,4-D RoundUp,glyphosphate Most widely used herbicide in the US. Between 54-60 million pounds annually Can be degraded in 2 weeks in agricultural soils

Inorganic wastes contain no Carbon, include heave metals Although found in nature humans are responsible for accumulating them into abnormally found amounts Mercury—in batteries Nitrite—fertilizer runoff Selenium, Arsenic Uranium Acid mine drainage

Bacterial communities Communities of bacteria can handle even nuclear waste Highly contaminated waste sites have found bacteria eating the uranium and breaking it down to less water soluble compounds

Acid mine drainage Using microbial communities to clean the heavy metals

Hazardous waste are creating new fields of study Microbial technology Limiting factors for critical processes & significant organisms Identification of key biotic interaction Structure and function of food webs Environmental biotechnology Cleaning effluents of treatment waste Alternative and ecofriendly processes Alternative and ecofriendly products