Question: Investigation. Riverdale Mills Corp. makes plasticcoated steel wire products using a water-based cleaning process that generates acidic and alkaline wastewater. To meet federal clean-water requirements, Riverdale has a system within its plant to treat the water. It then flows through a pipe that opens into a manhole-covered test pit outside the plant in full view of Riverdale's employees. Three hundred feet away, the pipe merges into the public sewer system. The Environmental Protection Agency (EPA) sent agents to inspect the plant. Without a search warrant and without Riverdale's consent, the agents took samples from the test pit. Based on the samples, Riverdale and James Knott, the company's owner, were charged with criminal violations of the federal Clean Water Act. The defendants sued the EPA agents and others, alleging violations of the Fourth Amendment. What right does the Fourth Amendment provide in this context? Should the agents be held liable? Why or why not? [Riverdale Mills Corp. v. Pimpare, 392 F.3d 55 (1st Cir. 2004)]