A leak in Mid-Columbia Medical Center’s oxygen tank on the corner of Oregon and 19th Streets in The Dalles shut down all car and foot traffic in that neighborhood for a brief period of time this morning.  An MCMC spokesperson says the hospital shut off the oxygen from the main line, and repairs began at 8 a.m.  Traffic was allowed to continue in the area a few minutes later.  The hospital is running on what it terms “an abundant supply” of back-up oxygen until the repairs are made, and does not foresee any additional impact to patient care or access to the hospital.