Siting a Wastewater Treatment Plant
A county of 180,000 people must site a new wastewater treatment plant within five years. Site A is 40 acres of floodplain beside the river that supplies the county's drinking-water intake two miles downstream. Site B is 35 acres of prime farmland adjacent to a census tract where median household income is $31,000. Site C is 50 acres of a former steel plant, partially remediated, served by rail and a state highway, one mile from a wetland. The county's bond capacity is $60 million. Full remediation at Site C is estimated at $18 million, and acquiring Site B would require eminent domain.
1. Rank the three sites using geographic and planning criteria, and explain the tradeoffs.
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Site C is the strongest candidate despite its cost. Its situation is good - highway and rail access, already industrial, within existing infrastructure - and brownfield reuse is a standard planning preference. The costs are real: $18 million in remediation, wetland proximity, and residual contamination risk that must be monitored.
Site A should rank last. Placing a treatment plant in a floodplain upstream of a drinking-water intake creates a hazard exactly where failure is most damaging; flood frequency and downstream position are disqualifying, not merely costly.
Site B is intermediate. It has adequate land and likely lower construction cost, but converting prime farmland is a permanent loss, and eminent domain next to a low-income tract raises an environmental-justice problem: the people bearing the nuisance are not the people receiving the benefit.
2. Which additional data layer would most likely change your ranking?
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Flood frequency and groundwater data for Site A, and a wetland delineation plus contamination-plume map for Site C. Those are the two places where unknown physical geography could overturn a planning judgment.
If Site C's plume is migrating toward the wetland, remediation cost and long-term liability rise sharply and the site may drop behind B. If Site A's floodplain turns out to be outside the regulatory floodway and the intake can be protected, A becomes less clearly disqualifying - though the downstream position remains a serious concern.
Notice that the ranking is not a formula. It is an argument from criteria - hazard exposure, infrastructure, land conservation, equity, cost - and different defensible weightings produce different answers. The exam-style skill is stating the criteria, applying them to specific facts, and acknowledging what would change your mind.
3. How should environmental-justice concerns at Site B be handled rather than merely noted?
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Proximity alone is not the whole analysis; process and cumulative burden matter. The relevant questions are whether the affected tract already hosts disproportionate industrial or waste facilities, whether residents had meaningful notice and voice before siting, and whether mitigation - buffering, odor control, local hiring, compensation - is built in.
If the county can avoid the question by choosing C, that is the cleaner answer, because siting a plant next to a low-income tract by eminent domain concentrates a burden on people with the least capacity to resist. If B remains under consideration, the county should document cumulative burden, hold hearings in the tract itself, and commit to enforceable mitigation.
Treating equity as a checkbox is itself the failure mode the analysis should catch.