If your job description is like most, it is impossible to do everything on it.  So prioritize the various tasks listed in your job description (number them in order of importance, 1-10). Then try to match them with the priorities of the job according to the personnel committee.  Once you and the personnel committee get the same list of priorities, you have permission to let go of #5 this year while you focus on #1-#4--and the staff will back you.  Do this every year; if priority #1-#4 take your time this year, next year you can probably prioritize something else.