The US Supreme Court ruled against the Trump Administration and DoJ views that groundwater disposal should be exempted from certain requirements of the Clean Water Act. The ruling negates a prior loophole that underground injection wells would not be liable for potential environmental damages from potential “indirect” contamination of freshwaters (i.e., rivers, lakes, streams, underground aquifers) and even the ocean. In practice, there have been limited cases of injection wells contaminating these waters, but these incidences are increasing rapidly as more testing is done. Moreover, when an underground aquifer (which currently supply about one-third of global freshwater) is contaminated, the effects are difficult to reverse.
Here is the link to the full report.