BM>car.  How, in a case like this, can I make the would-be good Samaritan
  >understand, even before he gets out of his car, if possible, that I want
  >privacy, not help?
I can understand your problem; but short of a big "Cholera" sign 
I don't know how you can keep people away.  Even a sign that you are
taking a nature call would attract curious people.  Good luck.
On the other hand, maybe a "Drug Checkpoint" sign would work. 
CHARLES HUNTER
 * 1st 2.00 #9124 * Logic is a wreath of pretty flowers that smell bad.
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