Environmental Engineering Reference
In-Depth Information
Cancel the units:
Solve the math:
ii. How many coal cars will be needed to operate the power plant for the day? (2 points maximum— 1
point for setting up the problem, 1 point for arriving at the correct answer)
or simplified
Set up the problem, cancel the units, and simplify the units:
Solve the math:
Final answer:
iii. How many trains will be needed to power the plant for a day if the train pulls 80 coal cars? (1 point
maximum)
B. Coal mines in the west tend to be strip mines. Describe how a strip mine is mined to obtain the coal.
Explain one impact on aquatic ecosystems from strip mining. (2 points maximum)
• 1 point: Strip mining, one form of surface mining, is the removal of soil and rock that are above the
coal. Large "earthmover" equipment is needed to remove the soil and rock. Then additional ma-
chines (excavators) remove the coal.
• 1 point: When it rains, the water may wash soil and small rocks down into the stream, increasing tur-
bidity, which can then decrease photosynthesis and alter the entire ecosystem.
• 1 point: Acid drainage can occur. During mining, when rock is exposed, naturally occurring sulfide
minerals also are exposed. When it reacts with oxygen and water, the sulfide turns into sulfuric acid.
This can run off into waterways and become toxic to organisms.
