Help me decode some fine print

I am thinking of getting this independence air flat-rate flying pass for college students this summer. There is a base fee of $250 and then you just pay taxes. But does this mean that you pay taxes per destination?

"8. All fares (including the $0 fare) do not include segment fees of up to $6.40 per one-way trip, the September 11th Security Fee of up to $5.00 per one-way trip and Passenger Facility Charges of up to $9.00 per one-way trip."

So if I go Chicago-->DC-->Palm Beach, do I pay the $20 taxes twice?

btw: what airline offers that?

flyi.com

all the references are to "segment fees" and "one-way trips"

NORFOLK, Va. (AP) - Independence Air will stop flights to
Norfolk at the end of May as the low-fare carrier tries to avoid
bankruptcy.
The Dulles-based airline also plans to reduce service at many of
the 41 cities it serves.
Independence Air spokesman Rick DeLisi says they decided to pull
their five daily flights out of Norfolk because it's so close to
Dulles.
He says the airline will return 18 of its 87 regional jets to
its lease partner as part of a financial restructuring.
Norfolk airport officials said Independence's departure will be
a blow because its low fares drove down ticket prices to Dulles.
Kenneth Scott, the Norfolk airport's executive director, says
fares to Dulles hovered around 600 dollars round trip before the
airline arrived in June. Round trip fares on Independence range
from 68 to 218 dollars.

http://blogs.flyertalk.com//blogs/viewwing/archives/2005/02/warning_off_ind.html

http://www.washingtonpost.com/wp-dyn/articles/A17560-2005Feb11.html

The parent of financially troubled Independence Air said late yesterday that a lender had repossessed one of the airline's 73 leased regional jets.