Time
class 1-2 operators need _____ hrs of education to renew
Class 3-4 operators need_____ hrs of education to renew
12,24
this living thing can change pH, taste, odor
Algal blooms
destratification in lakes and ponds happens
spring and autumn
is any physical link between potable water supply and one of unknown or questionable quality
cross-connection
When do you backwash a filter?
6-10ft of loss head
NTU > 0.3
greater than 100hrs
Flocculation is a slow steady mix greater detention time is better for the floc the minimum time is:
the idea time is:
30min
1-2hrs
Is when the supply pressure drops?
is when the customer side has increased presser?
back-siphonage
backpressure
what is the Langelier saturation index formula
pH(A) - pH(S)
this valve offers no protection and is ineffective
single check valve
are the least effective media at removing dissolved solids
rapid sad filtering
hold times for
Heterotrophic plate counts
total coliform
Giardia and cryptosporidium
6hrs
30hrs
96hrs
protecting on the consumer side is?
Protects the supply side of the pipe?
Isolation
Containment
must be 2x the inside diameter or 1in whichever is bigger?
Air gaps
a higher pH means?
more basic and more hypochlorite and less hypochlorous acid
gallons treated per day are required to be a class 4 license/ plant
greater than 3,000,000
if a sample is positive for E.coli, the division of water must be contacted within
24hrs
Haloacetic acids Haa5 regulated annually at
Trihalomethanes are regulated at
Chlorite is reg monthly avg
60ppb
80ppb
1ppm
The regulated disinfectant though the entire system free chlorine
Chloramine: combined chlorine
0.2mg/l
0.5mg/l
are weaker disinfectant than chlorine but are more stable and make fewer DBPs
Chloramines
Ion exchange columns use what to recharge?
a salt brine
What is CT calculation and what does it determine
CT= contact time
helps determine chemical dose
your system has high TTHM levels and low HAA formation. How do you reduce the TTHM
Lower the pH
disrupts DNA of pathogen and has no DBP's
UV disinfection
Filter Turbidity is less than NTU goal
Max turbidity less than NTU in 95% of samples per month
NEVER to exceed NTU
0.10
0.30
1
membrane with the smallest filter size