1.  How many pounds of 65% HTH chlorine will be required to disinfect 400 feet 
     of 8-inch watermain at 50 ppm?

a.  .22 lbs b.  .68 lbs c.  3.68 lbs d.  10.45 lbs

2.  An 8-inch diameter pipe is flowing at 1.5 ft³/sec (cfs).  What is the velocity
     in ft/sec.?

a.  1.88 ft/sec b.  4.26 ft/sec c.  8.72 ft/sec d.  16.61 ft/min

3.  If a pipe must carry 350 gpm at a maximum velocity of 4 ft/sec, what diameter
     pipe will be required? 

a.  2 inch b.  6 inch c.  12 inch d.  2 ft. 6 inch

         4.  What is the rate of flow in cfs in a 6-inch pipe with water velocity of 3.5 ft/sec?            

a.  .69 cfs b.  4.22 cfs c.  5.12 cfs d.  6.22 gallons/sec

5.  A 1500 gpm high service pump transmits water to the distribution system through
     a 16-inch pipe.  What is the water velocity in ft/sec?

a.  1.2 ft/sec b.  4.2 ft/sec c.  2.4 ft/sec d.  2 ft/sec

         6.  A 12-inch watermain is reduced to a 6-inch watermain.  If the velocity in the 12-inch
              watermain is 2.5 ft/sec, what is the velocity in the 6-inch watermain?

a.  10 ft/sec b.  5 ft/sec c.  8.5 ft/sec d.  11 ft/sec

7.  Calculate the Langlier Index for a water with a calculated pH_s value of 8.69 and 
      an actual pH of 8.5. 

a.  -.19 b.  -.49 c.  2.2 d.   6

8.  The pH of stability (pH_s ) for your water has been calculated to be 8.8.  You are
     reading a pH of 9.4 today in your distribution system.  Is your water scale forming
     or corrosive?

a.  .6   forming b.  .6  corrosive c.  1.82  forming d.  2.222 corrosive

Lime Softening

9.  What is the molecular weight of hydrated lime? Ca(OH)₂

a.  2.6 b.  6.3 c.  56.1 d.  74.1

10.  What is the molecular weight of pebble lime? CaO

a.  3.4 b.  7.4 c.  35.6 d.  56.1

11.  What is the molecular weight of calcium carbonate? CaCO₃

a.  33.3 b.  48.6 c.  78.4 d.  100.1

12.  What is the molecular weight of calcium bicarbonate? Ca(HCO₃)₂

a.  25.1 b.  50.1 c.  162.1 d.  222.2

13.  How many pounds of hydrated lime would be required to treat 500,000 gallons
       of water to reduce the amount of calcium bicarbonate from 240 mg/l to 
       90 mg/l?

a.  86 lbs b.  116 lbs c.  202 lbs d.  286 lbs

14.  Find the amount of lime as CaO that would be required to reduce the amount
       of calcium bicarbonate from 200 ppm to 85 ppm in a plant with a 5600-gpm
       flow.

a.  266.3 lbs b.  506.1 lbs c.  1,331.5 lbs d.  2,663 lbs

15.  28,500 pounds of alum are added each month at a plant operating at 3.6 MGD,
       and the alum costs $8.00 per 100 pounds.  What is the total cost of the alum for
       the month?        

a.  $1,220 month b.  $1,550 month c.  $2,280 month d.  $3,352 month

16.  See above--total cost of the alum for the year?

a.  $14,640 year b.  $18,600 year c.  $27,260 year d.  $40,224 year

17.  What would the total cost of lime for one year if lime is fed at an average rate of
       65 ppm for a plant with a flow of 3600 gpm?  Assume the plant operates 7 days a
       week, 24 hours a day, and that the cost of the lime is $12.00 per 1000 pounds.

a.  $6,802 year b.  $12,308 year c.  $16,444 year d.  $28,002 year

18.  The pumping level in a well is 80 feet.  Water is pumped 2000 feet horizontally to
       an elevated storage tank 120 feet high.  The head loss in the pipe is approximately
       2.8 feet per 1,000 feet.  What is the total pressure in psi required by the pump?

a.  9 psi b.  29 psi c.  49 psi d.  89 psi

19.  The water level in a 50-foot diameter reservoir at 8:00 am is 21 feet.  The water
       level at 4:00 pm is 11 feet.  If the water is flowing into the reservoir at 220 gpm, 
       at what rate is the water being pumped out of the reservoir from 8:00 am to 
       4:00 pm?

a.  42 gpm b.  86 gpm c.  170 gpm d.  220 gpm

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