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There are thousands of subterranean coal fires in the world that, because of incomplete combustion, emit a wide variety of volatile and semivolatile organic compounds to the atmosphere, water, and soil at concentrations that could pose health risks to humans and wildlife. The main goals of this study were to (1) review methods that are used to characterize physical and chemical characteristics of coal-fire sites, (2) determine relationships between gas emissions and physical and chemical characteristics of coal-fire sites, using a combination of regression and multivariate statistical methods, and (3) determine the concentrations of volatile and semivolatile organic compounds in water and soil at two coal-fire sites in eastern Kentucky. More specifically: The objective of Chapter 1 was to review past works and list technologies used over time. Eight years of coal-fire collection technologies were reviewed. A variety of methods and technologies were identified. Qualitative and quantitative preferences were noted. The objective of Chapter 2 was to identify and list uncontrolled coal-fire variables. These variables include complete/incomplete combustion; fire temperature and size; distance to fire; relative humidity and moisture in the system; geology, geochemistry, and age of coal; condition of the mine, sampling time of day; sampling equipment differences; and human error. A secondary objective of this chapter was to determine which coal-fire gases have strong relationships by using the principal component analysis (PCA) software JMP. The strongest relationship was between CO and H2S. Temperature and CH4 were also important. This indicates that incomplete combustion and polynuclear aromatic hydrocarbon (PAH) formation are likely occurring, setting the stage for Chapter 3. The objective of Chapter 3 was to identify and define the extent of soil and water hydrocarbon contamination at the Truman Shepherd and Lotts Creek coal fires in eastern Kentucky. No groundwater contamination was detected at either location. Soil contamination was found at both, but was much higher at Lotts Creek, potentially because of sorption onto soil organic matter (which is reduced at Truman Shepherd by an excavation attempt) and other physicochemical mechanisms. Soil contamination was localized to relatively small areas around coal-fire vents. Based on the results, future studies should consider: Attempting to duplicate these results in other geologic regions Quantifying greenhouse gas emissions from coal fires to consider their contribution to climate change. Coal-fired power plants are regulated, but coal fires, which produce many more harmful gases, are not Determining the feasibility of an oxygen-injection system to engender more complete combustion, therefore possibly reducing harmful gases Determining the feasibility of electricity production from coal fires Adopting a consistent federal coal-fire policy

Dagens samhälle är beroende av el, allt från att få rent vatten i kranen till att kunna tanka bilen kräver el. Vattenkraftverk står för nästan 50% av dagens elproduktion i Sverige vilket medför att vattenkraft är en väsentlig verksamhet för att få samhället att fungera. Ur ett miljöperspektiv anses vattenkraft vara mer miljövänlig än el som produceras på fossila bränslen. I och med den stora rollen vattenkraft spelar i dagens samhälle är det viktigt att förebygga eventuella olyckor och produktionsstopp, till exempel bränder. Bränder har tidigare förekommit på vattenkraftverk runt om i världen. Colorado är ett exempel där det började brinna i det brandfarliga materialet som arbetades med i en tunnel på stationen. Detta resulterade i en brand där flera arbetare blev instängda i en tunnel under marken, samtliga omkom då det endast fanns en utrymningsväg. I vattenkraftstationer som är belägna under marken är det vanligt förekommande att det endast finns en utrymningsväg. Olyckan påvisar den komplexitet som finns vid dimensionering av vattenkraftstationer under marken. Syftet och målet med detta projekt har varit att identifiera brandrisker på två vattenkraftverk och finna passande åtgärder för att minimera och förebygga dessa. För att uppnå projektets mål har bland annat en litteraturstudie genomförts för att ge en förståelse över problem som kan uppstå. En riskidentifiering genom platsbesök har också genomförts för att se hur det ser ut i verkligheten på de två vattenkraftstationerna. Det har även gjorts en datasimulering för att ge en uppfattning av rökspridningen, denna datasimulering har genomförts med hjälp av Fire Dynamics Simulator (FDS). Litteraturstudien påvisade, genom statistik från MSB:s databas IDA, att transformatorbränder är en av de största riskerna i anläggningar under marken. Vid platsbesöket på Messaure, ett vattenkraftverk, fanns det endast lokaltransformatorer placerade under marken. Dessa lokaltransformatorer var av typen torrtransformator vilket medför en mindre brandrisk. Tidigare fanns även övriga transformatorer under mark men dessa är flyttade ovan mark för att minimera brandrisken. Till skillnad från Messaure fanns Akkats, ett vattenkraftverk, transformator placerad under mark i en egen transformatorhall vilket utgör en egen brandcell. Entrén till denna fanns i direkt anslutning till tillfartstunneln som också används för utrymning. För att undersöka hur mycket en brand i transformatorhallen skulle påverka utrymningen valdes detta utrymme för en FDS-analys. Den slutsatsen som kan dras är att skulle dörren stå öppen skulle en brand i transformatorn ha en stor negativ inverkan på utrymningen. Rökutvecklingen skedde snabbt och röken strömmade tidigt ut i tillfartstunneln vilket medförde en påverkan på all utrymning. Vanligtvis ska dörren till transformatorhallen vara stängd men den kan lätt glömmas öppen i och med att det inte finns en dörrstängare. En kostnadseffektiv förbättring vore att installera en dörrstängare, det skulle kunna rädda liv. / Today's society is dependent on electricity, from getting clean water in the faucet to being able to put fuel in the car electricity is required. Hydroelectric power plants account for almost half of today's production of electricity, which means that hydropower is a vital factor for the community to function. From an environmental perspective, hydropower is considered more environmentally friendly than electricity produced from fossil fuels. Since hydroelectric power plants play a big role in society makes it very important to prevent possible accidents and hold-ups in production, such as a fire. Fires have occurred at hydropower plants around the world. Colorado is an example where the fire started in the flammable material that was being used in a tunnel at the hydropower plant. This resulted in a fire where several workers were trapped in a tunnel underground, all workers died since there was only one escape route. In hydropower stations located underground, it is common that there is only one escape route. The accident demonstrates the complexity that exists in the dimensioning of hydropower stations underground. The purpose and goal of this project has been to identify fire risks at two hydropower plants and how to minimize and prevent them. In order to achieve the project's goals, a literature study has been conducted to provide an understanding for the problems that may arise. A risk investigation was also conducted at the hydropower plants to see what they look like in the reality. A computer simulation has also been made to give an idea of the smoke spread. This computer simulation has been performed using the Fire Dynamics Simulator (FDS). The literature study showed, through statistics from MSB's database IDA, that transformer fires are one of the biggest risks in underground facilities. During the visit to Messaure, a hydroelectric power plant, only the local transformers were placed below the ground. These local transformers were of a dry-transformer type, which results in a smaller fire hazard. Previously, there were also other transformers underground, but these are moved above ground to minimize the fire hazard. Unlike Messaure, Akkat's, a hydroelectric power plant, transformer was placed underground in a separate transformer hall, which is a separate fire cell. The entrance to this was directly adjacent to the access tunnel which is also used for evacuation. To investigate how much a fire in the transformer hall would affect the evacuation, this space was chosen for an FDS analysis. The conclusion that can be drawn is that if the door should be left open, a fire in the transformer would have a major negative impact on the evacuation. Smoke quickly streamed into the access tunnel, which has an effect on all evacuation. The door should always be closed . However, there is no automatic door closer, which can result in the door being left open. A cost-effective improvement would be to install a door closer, which could save lives.