The answer is petroleum
hope this helps!
Answer: Mining is an activity which the earth is dig to obtain minerals and oil reservoirs.
Explanation:
The two environmental consequences that are responsible for filling the valleys are soil erosion and downstream mining causing the contamination of the neighboring water source. Soil erosion is resultant of the mining activity causing the trees to be uprooting from their site and making soil prone to the affect of physical factors like wind and water.
The U.S. has more than 87,000 dams greater than six feet high (and two million overall). While many dams continue to provide benefits such as flood control, irrigation, and water supply, for other dams the cost of maintenance or the negative effects on communities, fish, and tribes justifies their removal.
Dam owners and regulators decide whether to remove a dam by weighing many factors including: the cost of removal and the ability to replace any lost power generation against avoided long-term maintenance; safety concerns; benefits to endangered fish populations; increased recreational and commercial fishing; and restoration of cultural values of nearby tribes.
By 2020, roughly 70% of dams will be more than 50 years old, inviting us to reconsider the value to the public of long-term investments in this infrastructure.
I think its B C D are the ones that fit the most
