landfills, dust, odor, noise pollution, and reduced local property values. landfill gas gases are produced in landfills due to the anaerobic digestion by microbes. in a properly managed landfill this gas is collected and used. its uses range from simple flaring to the landfill gas utilization and generation of electricity. landfill gas monitoring alerts workers to the presence of a build-up of gases to a harmful level. in some countries, landfill gas recovery is extensive; in the united states, for example, more than 850 landfills have active landfill gas recovery systems. a gas flare produced by a landfill in lake county, ohio regional practice a landfill in perth, western australia south east new territories landfill, hong kong canada landfills in canada are regulated by provincial environmental agencies and environmental protection legislation. older facilities tend to fall under current standards and are monitored for leaching. some former locations have been converted to parkland. european union in the european union, individual states are obliged to enact legislation to comply with the requirements and obligations of the european landfill directive. the majority of eu member states have laws banning or severely restricting the disposal of household trash via landfills. india landfilling is currently the major method of municipal waste disposal in india. india also has asia's largest dumping ground in deonar, mumbai. however issues frequently arise due alarming growth rate of landfills and poor management by authorities. on and under surface fires have been commonly seen in the indian landfills over the last few years. united kingdom landfilling practices in the uk have had to change in recent years to meet the challenges of the european landfill directive. the uk now imposes landfill tax upon biodegradable waste which is put into landfills. in addition to this the landfill allowance trading scheme has been established for local authorities to trade landfill quotas in england. a different system operates in wales where authorities cannot 'trade' amongst themselves, but have allowances known as the landfill allowance scheme. united states u.s. landfills are regulated by each state's environmental agency, which establishes minimum guidelines; however, none of these standards may fall below those set by the united states environmental protection agency (epa). permitting a landfill generally takes between five and seven years, costs millions of dollars and requires rigorous siting, engineering and environmental studies and demonstrations to ensure local environmental and safety concerns are satisfied. types municipal solid waste: takes in household waste and nonhazardous material. included in this type of landfill is a bioreactor landfill that specifically degrades organic material. industrial waste: for commercial and industrial waste. other related landfills include construction and demolition debris landfills and coal combustion residual landfills. hazardous waste or pcb waste: polychlorinated biphenyl (pcb) landfills that are monitored in the united states by the toxic substances control act of 1976 (tsca). microbial topics the status of a landfill's microbial community may determine its digestive efficiency. bacteria that digest plastic have been found in landfills. reclaiming materials one can treat landfills as a viable and abundant source of materials and energy. in the developing world, waste pickers often scavenge for still-usable materials. in commercial contexts, companies have also discovered landfill sites, and many have begun harvesting materials and energy. well-known examples include gas-recovery facilities. other commercial facilities include waste incinerators which have built-in material recovery. this material recovery is possible through the use of filters (electro filter, active-carbon and potassium filter, quench, hcl-washer, so2-washer, bottom ash-grating, etc.). alternatives in addition to waste reduction and recycling strategies, there are various alternatives to landfills, including waste-to-energy incineration, anaerobic digestion, composting, mechanical biological treatment, pyrolysis and plasma arc gasification. depending on local economics and incentives, these can be made more financially attractive than landfills. restrictions countries including germany, austria, sweden, denmark, belgium, the netherlands, and switzerland, have banned the disposal of untreated waste in landfills. in these countries, only certain hazardous wastes, fly ashes from incineration or the stabilized output of mechanical biological treatment plants may still be deposited.