Companies in Florida, and possibly other areas with porous rock, may continue to use the option of treating their wastewater before injecting it, even if it doesn’t pass the no-fluid-movement test.

The city of Miramar, joined by the Sierra Club and several other municipal water treatment groups in Florida, filed a petition against the EPA’s federal underground injection control requirements for Class I municipal disposal wells in Florida. According to court documents, the petitioners argued that the 2005 regulation failed to protect underground sources of drinking water as the no-fluid-movement standard did.

Sierra Club is particularly concerned that secondary treatment and high-level disinfection, while they might take care of biological pathogens, fail to address the potential entry of industrial and other non-biological contaminants into groundwater. However, the court agreed with the EPA, believing that because it’s impossible to track the flow of such injections in such conditions, the only logical method of control, while still allowing underground injection, is to do so at the source.

The case is Miramar v. EPA.