I was a seismic analyst/technician in the USAF (1969-73). Our training detachment was at Rocky Mountain Arsenal, just north of Denver's old Stapleton Airport. DoD caused WW I/II nerve and mustard gas to be stored at RMA. Shell Chemical Company built a plant at RMA to process those gasses into inert liquids, and then pump those liquids into 10,000 foot holes in the ground (at RMA).
Our RMA seismometers routinely detected minor earchquakes caused by those inert liquids, but since our mission was classified, we couldn't tell anyone. In the meantime, the Denver news media trumpeted that the SEISMIC ACTIVITY IN DENVER PORTENTS THE NEXT "BIG ONE."
In reality, the pumped liquids were lubricating the (very minor) geological faults under Denver, causing the release of stress that actually reduced the risk of a more vigorous quake. Go figure.