The evening all started at 20:07 hrs with an on station call from a resident at 1081 Park Ave. They believed that they were smelling natural gas in and around their home. E43-3 responded with a crew of (6) to investigate. Crews sampled the air inside and outside of 1081 and 1091 Park Ave with nothing found. The crews also checked out the regulator house @ Park Ave and Thorne Dr. There was an obvious presence of natural gas at that location. Columbia Gas was then notified. 43 Units cleared the scene at 20:40 hrs. About 1 hour later 21:53 hrs Station 43 was called out to 382 Hancock Street. for a smell of natural gas. E43-3 responded with a crew of (4) E43-2 crew of (2) and Chief 43 (POV). Chief 43 on scene to find a strong smell of gas coming from the gas meter. 43 crew shut off gas service to 382 and 384. Columbia Gas responded to the scene to verify the leak. Thru conversation with the gas Co. official this was his  10th call in the area that evening. Official believed that Columbia Gas was adding more MERCAPTAN to system, making the smell more noticeable. 43 units cleared the scene at 22:42 hrs.