HILL. 141


 rhe sp ce on fhe lower level underneath the mezzanine is d'ted to
the Ionener a d wash-water pumps. Three Wheeler surf6e con-
den rs, equipped with steam jet air pumps capable of maintning a
28-i. vacuum, are used. Each of the three condensers receives the exhaust
fron0a high nd a low lift pump. Cooling water for the condensers i taken
frothe lo lift mp discharge. As the temperature of the rive water
cl y app ximat a that of the air, it was felt that it would be untsirable
tos1 firtr inci ease the temperature of the water supplied to #te city.
For is ron, te cooling water after leaving the condensers ~carried
to a ewEr ad wa ed. Duplicate 350 gal. per minute water mot#*driven
 a-waer ump have been installed. These are automatic con-
trolld b as reg ator valves operated by water pressure from tS wash-
wat4tt .
 he p iping station is so arranged that from the high-lift por the
engi eer watcl the operation of the entire pumping plant. ,ie low-
lift ad gepi rators on the lower level are in full view of the operator.
Ope tios the condenser room may be seen through openingi.in the
mez r e fl or. l gages are located on or plainly visible from tl~ floor.
 ie 0O shews a longitudinal and transverse section threVgh the
pu ing sta ion. 'Figure 11 is a plan of the pumping equipment ad main
pipi g. g e 122 is a photographic view taken from the floor of the low-
lift i T m. I, shows the high-lift pump room above and the ~ondenser
roo b w he mezzanine floor.,
 tPnt. The treatment plant of 12-15 million ggL initial
rate ca acy has been designed so that by the addition of new tmits the
cap ity ka r readily be enlarged to 36 million gal. daily without ipairing
the iymne y. T\he plant comprises mixing tanks and sedin1dhtation
 basic s, checal house, filter house, gravity mechanical filters, and filtered
water reservr.
 Mixng Tanks Eight lime-mixing tanks, each 24 ft. square, and eight
aluminum s phat( mixing tanks, each 18 ft. 8 in. square, have been con-
stlrued.] I ach mixing tank is provided with a bronze impeller 'et in a
14-i draft ube and operated by a'one-horse-power motor. Ea& motor
is c"trolle by a! individual switch. As no covering .is proved for
mix tank or sedimentation basins, the motors are protected by copper
hoo Tw mixing g tanks, separated by a top baffle, are always used in
seri The chemical solutions enter the mixing tanks through an orifice
box ro de with brass orifice plate, so as to give equal dosage to pi tanks
in u .
 edi tionasins. Two lime-settling basins, each of.one millionn
 gal.apa t or sicient to give a 4-hour detention period when operating
 at t e n rate and two decolorizing basins, each three-quartrs of a
 .n paeit r, giving a detention period of three hours, are provided
 (see ig 1 14, id 15). As previously stated, these basins ca-be used
 eith in ere or i parallel.