Grade 1 Water Distribution Study Questions
With Correct Answers 2024
Which .agency .sets .legal .limits .on .the .concentration .levels .of .harmful .contaminants .in
.potable .water .distributed .to .customers?
a. .National .Primary .Drinking .Water .Regulations .Agency
b. .US .EPA
c. .US .Public .Health .Service
d. .Occupational .Health .and .Safety .Administration .- .correct .answer.B
The .number .of .monthly .distribution .system .bacteriological .samples .required .is
a. .based .on .the .water .withdrawal .permit .limit
b. .based .on .the .system .size
c. .based .on .population .served
d. .different .for .each .state .- .correct .answer.c
What .is .the .maximum .contaminant .level .for .TTHM .in .the .united .states? .- .correct
.answer..08
Under .the .Surface .Water .Treatment .Rule, .disinfection .residuals .must .be .collected .at .the
.same .location .in .the .distribution .system .as?
a. .coliform .samples
b. .total .tthms
c. .disinfection .by .products
d. .alkalinity, .conductivity, .and .pH .for .corrosion .studies .- .correct .answer.a
Iron .can .cause ."red .water" .and .thus .customer .complaints .when .its .concentration .is .above
.its .secondary .maximum .contaminant .level .of:
a.) .0.01 .mg/L
b.) .0.05 .mg/L
c.) .0.10 .mg/L
d.) .0.30 .mg/L .- .correct .answer.d
The .goal .of .the .Surface .Drinking .Water .Act .is .for .each .________ .to .accept .primary
.enforcement .responsibility .(primacy) .for .the .operation .of .the .state's .drinking .water
.program.
a. .state
b. .water .treatment .plant
,c. .operator
d. .municipality .- .correct .answer.a
What .is .the .objective .of .the .Total .Coliform .Rule?
a. .to .provide .Cryptosporidium .protection .in .new .facilities
b. .to .ensure .safe .levels .of .lead .and .copper
c. .to .protect .the .public .from .exposure .to .giardia .lamblia .and .crypto
d. .to .promote .routine .surveillance .on .system .water .quality .to .search .for .fecal .matter
.and/or .disease-causing .bacteria .- .correct .answer.d
Which .agency .sets .standards .on .concentration .levels .of .harmful .contaminants .in .drinking
.water? .- .correct .answer.USEPA
Explain .the .difference .between .the .different .tiers .of .violations. .Which .one .is .the .most
.serious? .- .correct .answer.Tier .1 .is .an .acuty .MCL .violation .requiring .public .notification
.within .24 .hrs. .Tier .2 .notification .must .occur .within .30 .days. .Tier .3 .require .notification
.within .1 .year.
A .positive .E. .coli .test .must .be .reported .to .the .primacy .health .agency .within .what .period .of
.time? .- .correct .answer.24 .hours
How .is .the .required .number .of .monthly .bacteriological .samples .determined? .- .correct
.answer.Population .served
What .is .the .action .level .for .lead .in .first .draw .samples .taken .from .customer .taps? .- .correct
.answer..015 .mg/L
A .water .system .is .designated .a .community .public .water .system .if .it .serves .how .many
.homes? .- .correct .answer.15 .or .more
What .authority .provides .specific .water .sampling .instructions? .- .correct .answer.the .state
.primacy .agency
According .to .the .Lead .and .Copper .Rule, .what .is .the .action .level .for .lead? .- .correct
.answer.0.015 .mg/L
Determine .the .detention .time .in .hours .for .the .following .water .treatment .system:
.Distribution .pipe .from .water .plant .to .storage .tank .is .549 .feet .in .length .and .14 .inches .in
.diameter. .Storage .tank .averages .2,310,000 .gallons .of .water .at .any .given .time. .Flow
.through .system .is .6.72 .mgd. .- .correct .answer.8.3 .hours
divide .daily .flow .by .24 .hours .in .a .day .(280,000)
then .divide .280,000 .into .tank .capacity
, If .chlorine .is .being .fed .at .a .rate .of .260lb/day .for .a .flow .rate .of .23cf/s, .what .should .be .the
.adjustment .on .the .chlorinator .when .the .flow .rate .is .decreased .to .16 .cf/s .if .all .other
.parameters .were .to .stay .the .same? .- .correct .answer.180lb/day
260/23=x/16
divide .260 .by .23, .then .multiply .that .by .16
How .many .gallons .of .sodium .hypochlorite .solution .that .contain .12.1% .available .chlorine
.are .needed .to .disinfect .a .1.5ft .diameter .pipeline .that .is .283 .feet .long, .if .the .dosage
.required .is .50 .mg/L? .Assume .the .sodium .hypochlorite .is .9.92 .lb/gallon. .- .correct
.answer.1.3 .gallons .sodium .hypochlorite
sodium .HCl=[(mil .gal)(dosage)(8.34)]/[%avail .Cl2/100%]
A .storage .tank .has .a .60ft .radius .and .averages .25.5ft .in .water .depth. .Calculate .the
.average .detention .time .in .hours .for .this .storage .tank, .if .flow .through .the .tank .averages
.2.91 .mgd .during .the .month .in .question. .- .correct .answer.17.8 .hours
A .24in .pipeline, .427ft .long, .was .disinfected .with .calcium .hypochlorite .tablets .with .65%
.available .chlorine. .Determine .the .chlorine .dosage .in .mg/L, .if .7lb .of .calcium .hypochlorite
.was .used. .Assume .that .the .hypochlorite .is .so .diluted .that .it .weighs .8.34lb/gal. .- .correct
.answer.54 .mg/L
CaHCl(lb/day)= .[(mgd)(dosage)(8.34)(100%)]/[%available .Cl2]
Head .is .measured .in
a. .absolute .pressure
b. .gauge .pressure
c. .feet
d. .foot-pounds .- .correct .answer.c
A .plat .is .
a. .a .map
b. .a .corrosion .point .on .a .pipe
c. .an .organelle .found .in .some .protozoans
d. .a .highly .corrosive .soil .type .- .correct .answer.A
At .which .time .of .day .is .the .age .of .the .water .stored .in .the .distribution .system .the .highest?
a. .Early .morning
b. .Late .morning
c. .early .afternoon
d. .late .evening .- .correct .answer.a
Water .mains .should .primarily .be .sized .based .on .
a. .earthquake .potential
b. .peak .domestic .and .commercial .demands
With Correct Answers 2024
Which .agency .sets .legal .limits .on .the .concentration .levels .of .harmful .contaminants .in
.potable .water .distributed .to .customers?
a. .National .Primary .Drinking .Water .Regulations .Agency
b. .US .EPA
c. .US .Public .Health .Service
d. .Occupational .Health .and .Safety .Administration .- .correct .answer.B
The .number .of .monthly .distribution .system .bacteriological .samples .required .is
a. .based .on .the .water .withdrawal .permit .limit
b. .based .on .the .system .size
c. .based .on .population .served
d. .different .for .each .state .- .correct .answer.c
What .is .the .maximum .contaminant .level .for .TTHM .in .the .united .states? .- .correct
.answer..08
Under .the .Surface .Water .Treatment .Rule, .disinfection .residuals .must .be .collected .at .the
.same .location .in .the .distribution .system .as?
a. .coliform .samples
b. .total .tthms
c. .disinfection .by .products
d. .alkalinity, .conductivity, .and .pH .for .corrosion .studies .- .correct .answer.a
Iron .can .cause ."red .water" .and .thus .customer .complaints .when .its .concentration .is .above
.its .secondary .maximum .contaminant .level .of:
a.) .0.01 .mg/L
b.) .0.05 .mg/L
c.) .0.10 .mg/L
d.) .0.30 .mg/L .- .correct .answer.d
The .goal .of .the .Surface .Drinking .Water .Act .is .for .each .________ .to .accept .primary
.enforcement .responsibility .(primacy) .for .the .operation .of .the .state's .drinking .water
.program.
a. .state
b. .water .treatment .plant
,c. .operator
d. .municipality .- .correct .answer.a
What .is .the .objective .of .the .Total .Coliform .Rule?
a. .to .provide .Cryptosporidium .protection .in .new .facilities
b. .to .ensure .safe .levels .of .lead .and .copper
c. .to .protect .the .public .from .exposure .to .giardia .lamblia .and .crypto
d. .to .promote .routine .surveillance .on .system .water .quality .to .search .for .fecal .matter
.and/or .disease-causing .bacteria .- .correct .answer.d
Which .agency .sets .standards .on .concentration .levels .of .harmful .contaminants .in .drinking
.water? .- .correct .answer.USEPA
Explain .the .difference .between .the .different .tiers .of .violations. .Which .one .is .the .most
.serious? .- .correct .answer.Tier .1 .is .an .acuty .MCL .violation .requiring .public .notification
.within .24 .hrs. .Tier .2 .notification .must .occur .within .30 .days. .Tier .3 .require .notification
.within .1 .year.
A .positive .E. .coli .test .must .be .reported .to .the .primacy .health .agency .within .what .period .of
.time? .- .correct .answer.24 .hours
How .is .the .required .number .of .monthly .bacteriological .samples .determined? .- .correct
.answer.Population .served
What .is .the .action .level .for .lead .in .first .draw .samples .taken .from .customer .taps? .- .correct
.answer..015 .mg/L
A .water .system .is .designated .a .community .public .water .system .if .it .serves .how .many
.homes? .- .correct .answer.15 .or .more
What .authority .provides .specific .water .sampling .instructions? .- .correct .answer.the .state
.primacy .agency
According .to .the .Lead .and .Copper .Rule, .what .is .the .action .level .for .lead? .- .correct
.answer.0.015 .mg/L
Determine .the .detention .time .in .hours .for .the .following .water .treatment .system:
.Distribution .pipe .from .water .plant .to .storage .tank .is .549 .feet .in .length .and .14 .inches .in
.diameter. .Storage .tank .averages .2,310,000 .gallons .of .water .at .any .given .time. .Flow
.through .system .is .6.72 .mgd. .- .correct .answer.8.3 .hours
divide .daily .flow .by .24 .hours .in .a .day .(280,000)
then .divide .280,000 .into .tank .capacity
, If .chlorine .is .being .fed .at .a .rate .of .260lb/day .for .a .flow .rate .of .23cf/s, .what .should .be .the
.adjustment .on .the .chlorinator .when .the .flow .rate .is .decreased .to .16 .cf/s .if .all .other
.parameters .were .to .stay .the .same? .- .correct .answer.180lb/day
260/23=x/16
divide .260 .by .23, .then .multiply .that .by .16
How .many .gallons .of .sodium .hypochlorite .solution .that .contain .12.1% .available .chlorine
.are .needed .to .disinfect .a .1.5ft .diameter .pipeline .that .is .283 .feet .long, .if .the .dosage
.required .is .50 .mg/L? .Assume .the .sodium .hypochlorite .is .9.92 .lb/gallon. .- .correct
.answer.1.3 .gallons .sodium .hypochlorite
sodium .HCl=[(mil .gal)(dosage)(8.34)]/[%avail .Cl2/100%]
A .storage .tank .has .a .60ft .radius .and .averages .25.5ft .in .water .depth. .Calculate .the
.average .detention .time .in .hours .for .this .storage .tank, .if .flow .through .the .tank .averages
.2.91 .mgd .during .the .month .in .question. .- .correct .answer.17.8 .hours
A .24in .pipeline, .427ft .long, .was .disinfected .with .calcium .hypochlorite .tablets .with .65%
.available .chlorine. .Determine .the .chlorine .dosage .in .mg/L, .if .7lb .of .calcium .hypochlorite
.was .used. .Assume .that .the .hypochlorite .is .so .diluted .that .it .weighs .8.34lb/gal. .- .correct
.answer.54 .mg/L
CaHCl(lb/day)= .[(mgd)(dosage)(8.34)(100%)]/[%available .Cl2]
Head .is .measured .in
a. .absolute .pressure
b. .gauge .pressure
c. .feet
d. .foot-pounds .- .correct .answer.c
A .plat .is .
a. .a .map
b. .a .corrosion .point .on .a .pipe
c. .an .organelle .found .in .some .protozoans
d. .a .highly .corrosive .soil .type .- .correct .answer.A
At .which .time .of .day .is .the .age .of .the .water .stored .in .the .distribution .system .the .highest?
a. .Early .morning
b. .Late .morning
c. .early .afternoon
d. .late .evening .- .correct .answer.a
Water .mains .should .primarily .be .sized .based .on .
a. .earthquake .potential
b. .peak .domestic .and .commercial .demands
