Figure I Generalized map of the Wilbur Mining ... - University of Utah

2. near the County MuseLmi well (pr using the
actual, well); and
3. near the-end of the secondary supply Tine
{near the' County Courthouse')'.
Location 1 is best to minimize the effect on
adjacent wells in terms of water levels,, but may
cause premature temperature breakthrough. Location
2 elimi nates a return pipeTine to the production
zone and can use the existing museum well.
Temperature .effect would also be less due to lower
well water temperatures'in the injection area
(around 180° to l:9d°F). Location 3 could be considered
if .the primary heat, exchange facility were
eliminated, thus elirainatirig the heed for the
cTosed-lobp sjecondary p.ipellne. Geothermal water
would theri be desliyered directly to all buildings,
similar-to the Icelandic system. Each building
would then be required 'to supply their ortn heat exchanger
or use the fluid directly. Injection near
the end of the line would eliminate the need for a
return linei but may effect cold (60°' to 90°F) water
wells in the area,.
LBL reGonmends the^ second location, which is
the main dfe considered in this report. The drilling
and testing of at least two deep wells ih the
production area is necessary to better jevaluate
this Tecommendatian.
Dri'ltinq Costs - Klamath Basin. Well drilling
costs in the Klaraath Basin by cable or r-otary rigs
up to 3,000 feet are as follov/s:
$1,00 per inch of diameter-per foot of depth
in "soft" rock, and
$2.50 per inch of diamelier per foot of depth
iri "hard" rock up to 500 feet in defith.
For every additional 100-foot increment, add
41.00 per-foot of clepth-
Casing costs can be estimated at $1 ...05 per
inch of diameter per foot Of depth. Full^
depth casing is assuraed for all wells.
Using these costs, which include mobilization
arid dempbilization, and assuraing that the production
wells encounter the tsa'nie amounts of "hard" and
"soft" drilling that the test well log indicatesi
drilTihg and casing of a 1,OdO-ft well would cost
.$38,,'898 with full-depth casing. These costs are
expected to: rise apprpximately 10% in the very nearfuture,
and do not include costs for drilling mud,
additional air- compressprs if requiredi -foaraing
ageri'ts, etc.
Central Heat Exchangers
there are three basic'methods of transferring
the heat fro.m the gepthermal water to the buildirig
•air space. These are: 1} Use-, the geothermal water
directly iri the building heat emitters.; 2} Utilize
individual building hea't exchangers to transfer
heat-frora the geothermal water to a building cTo'sedwater
loop which in turn transfers heat to the heat
emitters; arid 3) Utilize large central heat exchanger's
to transfer heat to a di;strict. closed-war
ter loop and supply the buildings with fresh-heated
387
Lund, et. al.
water to be used in the heat emitters. Each system
has its advantages and disadvantages.
Even though the geothermal water in Klamath
Falls IS relativeiy pure, the dire.ct use in heat
emitters Is nol; recommended, especially in the fan
coil units of air handling systeras and small tube
baseboard units-. Experience with direct use at
OIT, Shadow Hills Apartments, Kingswood .Manor
apartmehts, arid several businesses in the East Main
Street .area indicate that life expectancy of the
fan coils may range from 1 1/2 Or 2 years to 12 or
15 years. At both Shadow Hills and Kingswood Manor,
leaks in fan coil units developed in 2.years or
less. Inspection of the units shows corrosion occurring
in the units priraariiy at soldered joints
and: changes in direction of the tubes at "the ends,,
although a few leaks have occurred in the main
body of units v/here tubes are straight. AtOJT,
five failures have occurred ir the 14 years the
Ltriits have been in service., again with most near
soldered joints, headers^ and at the ends df cOils,
There are no known di.rect uses of sraalT-finned tube
baseboaird units, bui: since the materials and methods
of construction are similar, it is assumed
they would have Simflar life tiraes. The exact nature
and cause of the failures, arid as, importantly
the difference in life of some units, is not. known
but is undeif study by OIT, Battel Te N-W. and
Radian Corporation iri a joint effort. Until the
cause of the failures .can be determined and/br .corrected,
direct use is not considered practical.
The-usual material's of construction of fan
coils are copper "tubes with pressed aluminum fins.
Other jriatenals which may have' To'nger life are
avai'lable, but reduce the heat transfer efficiency
and are more costly. As far as is kriown, all units
presently installed in any of the air handling
units in the buildings to be heated in the district
do have copper tubes.
Direct Use. The advantages Of direct use are
that water would.be supplied to the buildings at
higher temperatuice since heat would not be' lost in
a heat exchanger and the distriet construction
cost y/ould be much less'. The main disacfvantage' is
that iperhaps few customers v^oul'd hook up since the
reduced, cost of heat energy would be offset, or
p'er haps exceeded by, increased costs of maintenance.
Since experience is liraited, the cause of
failures is unknown, arid useful lives of components
apparently varies considerably even, within individual
systeras; maintenanGe and, replacement costs
ate next to impossible to evaluate., and an economic
comparison be'tween this- system and other's is
impossible,.
Indi vi dual Bui Tdinq Exchangers. The second
riethod, that of .supplying geothermal water to each
building where heat isr transferred -to a closed loop
within the .building, is a viable^ alternative and
offers several advantages but in th'e.overa-TT-, is
more mostly due to the economics of size.
Each :building would have its small heat exchanger,,
probably a plate type, with the associated
valves and controls to control the pressure flow.