----- Original Message -----

From: Randy Coslow rcoslow@hotmail.com
Sent: Sunday, February 20, 2000 11:36 AM
Subject: Thank you for your interest.

Dear Dr. Thomas,

Yes, indeed, we have many more questions for you. We sincerely appreciate
your assistance and your quick response. Here are some of our current questions:

(1) How would the pumping cost be lowered? It is my understanding that the
vertical building would have the highest point higher than the flat ground
configuration. Though we have placed the mechanical bar screen to rid the
sewage of grit and garbage before the final vertical pumping, the reduction
of the load by removing the garbage seems like it would be minimal compared
to the increased height of the building. All treatment of the domestic
sewage would occur after the pumping, as is the convention.

(2) In terms of efficiency, would there be an advantage to keeping the
domestic sewage local rather than the assumed alternative of having it
pumped long distances away from the city limits?

(3) Are we correct in saying the anaerobic digesters process wet sewage and
egg digesters process dewatered sludge?

(4) Would floating covers be required for the egg digesters? Our
understanding is that only pancake and anaerobic digesters are
designed to use such covers. Egg digesters seem to focus the sludge into the
bottom of the cone and therefore do not need the pressure increase from
a floating lid. We understand that the ventilation  for both the egg digester(s)
and the anaerobic digester(s) must be very well built.

(5) Should we place the egg digester(s) on top near the anaerobic
digester(s)? We am sure that gravity pumping would still work when this
change comes about and would concentrate all methane production to a
specific level in the structure. This level would be the strong-hold, the
level with the highest degree of reinforcement and safety of all the levels
due to its volatile nature.

(6) Would we have to incorporate more than one pump to move the mass of
sewage required the increased distance? Is there a standard vertical
distance (or ratio of height to flow rate) for an average industrial pump to
lift sewage?

(7) Would you happen to know of any architectural or construction firm (or
an individual you know who works for such a company) who could validate this
proposal?

We are extremely appreciative of your continued assistance,
-Randy J. Coslow