San Antonio---Firefighters, police officers, and CPS energy crews are monitoring a gas leak on the northwest side at 2380 Benrus Blvd. Crews were working in the area on Saturday and noticed that an underground tank was leaking. The tank could not be capped so crews are letting it vent to burn off. Firefighters do not anticipate any evacuation, but have part of Benrus closed off. Crews plan to be out monitoring the situation for several hours.