Internet research indicates that the Oxnard Kart track was most recently occupied by Jim Hall Kart Racing School, but was closed in 2004 when the area was returned to wetlands. Jim Hall would move to what appeared to be a copy, at least in some ways, of the old Oxnard facility, but that too was closed recently. Quite a shame to lose so many nice tracks. The Oxnard track looks like it would have been a blast to drive on!
Check out the video below: