What is the term that refers to all sediment deposited by running water?

Landfills are best left as open areas, such as golf courses or parks. This is because of the potential for
ongoing subsidence as the fill consolidates over time. Subsidence would be damaging to structures. A
second consideration is the potential for methane gas leakage. Keeping the area open provides a way
for methane gas to escape without building up to dangerous levels.

The greatest risk from this would be the possibility of an accident in which radioactive substances
might be dispersed into the upper atmosphere of the Earth. Alpha and Beta decay, for example, are
much more problematic where inhaled particles are concerned. Dust from an explosion at high level
could literally blanket the globe.

A residential community situated on top of a chemical waste dump began to experience serious health
issues related to leaking toxic substances. The problem became so acute that the President of the
United States declared the area a federal disaster area. This led to the evacuation and relocation of the
community and a very expensive cleanup effort. It was an important case because it prompted
Congress to enact legislation that provided money for toxic cleanup. This legislation also gave the
EPA authority to sue polluters for the cost of cleanup and relocation of victims.