[Gaffer]

Mr. Pickering was targeted by a longtime surveillance system called mail covers, a forerunner of a vastly more expansive effort, the Mail Isolation Control and Tracking program, in which Postal Service computers photograph the exterior of every piece of paper mail that is processed in the United States — about 160 billion pieces last year. It is not known how long the government saves the images.

You can safely bet that if the 'outside' data triggers against some keyword/address list, the entire CONTENTS are photographed too.

[Crazieman]

The images are saved for 30 days. Its supposed to be for high speed processing.

/postal clerk.

[tired&retired]

No wonder the Post Office loses so much money!!!

Wonder if they do the same with their own emails?

[Flick Lives]

Mr. Pickering was targeted by a longtime surveillance system called mail covers, a forerunner of a vastly more expansive effort, the Mail Isolation Control and Tracking program, in which Postal Service computers photograph the exterior of every piece of paper mail that is processed in the United States — about 160 billion pieces last year. It is not known how long the government saves the images.

...and yet the IRS can't keep email from its own director.