How Did the Orange County Water District Solve the Problem

Multiple Choice

How did the Orange County Water District solve the problem of saltwater intrusion into unconfined coastal aquifers?

A) It built a dam to block the seepage of saltwater into the aquifers.
B) It stopped using those aquifers as public water supplies.
C) It installed desalination plants to purify the water coming out of the aquifers.
D) It began to pump highly treated sewage wastewater into infiltrated wells.
E) It built sea walls along coastal areas to keep out advancing waves.