Officials in a small town near Denver have lifted a water advisory put in place over concerns of THC contamination after further testing revealed the water was safe on Saturday. On Thursday, authorities in Hugo had warned residents not to use the tap water because THC, the intoxicating chemical in marijuana, may have gotten into the water supply. After enlisting the help of the FBI and the Colorado Bureau of Investigation, further testing revealed that the THC contamination was limited to only one of the town's five wells, and the drinking supply was clear of the chemical. Police in Hugo say they believe one of the town's wells was tampered with, but they are still trying to determine whether it was deliberate. The investigation is ongoing.