Why won't propane smell go away, even after leak was repaired?

THE WAY TO DO IT. HIRE A PLUMBER LICENSED FOR PROPANE AND TELL HIM TO TEST FOR LEAKS. HE WILL PUT A WATER COLUMN ON THE PIPE AND PRESSURIZE IT. HE WILL LEAVE IT ON FOR THE PRESCRIBED TIME AND WHEN HE COMES BACK TO CHECK IT HE WILL TELL YOU IF IT HAS A LEAK OR NOT-FOR SURE!!! HE MAY WANT TO BUBBLE TEST SOME BEFORE DOING THE FULL TEST IN THE INTEREST OF SAVING TIME. THIS IS WHAT THEY HAVE TO DO WHEN THEY INSTALL A SYSTEM IN A HOME. THE CITY INSPECTOR THEN HAS TO VERIFY/CHECK THAT THE WATER COLUMN STAYS THE SAME BEFORE THE GAS IS ALLOWED TO BE APPLIED. THE POSSIBILITY OF A LEAK MUST BE ELIMINATED. A INSPECTOR WOULD NOT BE REQUIRED UNLESS THE PIPING IS CHANGED OR MODIFIED DUE TO A LEAK. PROPANE GAS IS HEAVIER THAN AIR AND POCKETS OF GAS FROM A LEAK DO NOT DISSIPATE EASILY LIKE NATURAL GAS.