Wastewater Lab Analyst Flash Cards
What determines the number of bacteriological samples collected per month??
# of people in the population
What is the concentration of the titrant used for alkalinity?
0.02 N
You have 0.01 mg of Manganese in 200 mL. How much do you have in 1L?
0.05 mg
1000 mg is equal to how many grams?
1 gram (g)
What is 10,025 rounded to three significant figures?
10,000
What magnification in a microscope is used to view filamentous bacteria?
100x
How to report TNTC on fecal coliform analysis?
1600 colonies/100 mL
According to the SDWA, to test TDS, filter a well-mixed sample, evaporate and dry to a constant weight, at what temp & for how long?
180 degrees celsius for 1 hour
What is the BOD incubation temp?
20 +/- 1 degree celsius
What temperature is volumetric glassware generally calibrated?
20 degrees Celsius
What is the hold time for COD?
28 days
What is the hold time for nitrate - nitrite?
28 days
What is the holding time for ammonia samples if preserved and refrigerated?
28 days
What reference document can you find OSHA regulations in?
29 CFR 1910
Total alkalinity endpoint?
4.5 pH
Primary drinking water standards are found where?
40 CFR 141
Where should you look to find approved methods (besides standard methods)?
40 CRF 136
What is the hold time for fecal coliform?
6 hours
What is the holding time for metals?
6 months/180 days
how should BOD samples be set up?
60 mL BOD bottles or greater
How many analyses must be completed in order to determine a MDL (minimum detection limit)?
7
What is the sludge concentration of 7% sludge?
70,000 *(multiply by 10,000)
Alkalinity titrations using phenolphthalein has a pH endpoint of what?
8.3
End point for phenolphthalein alkalinity?
8.3
What angle is light measured in a turbidity meter (nephelometer)?
90 degree angle
What purity ethanol is used to prepare some standards?
95% golden grain
Ammonia is released at what pH?
> 11
Fume hoods should be used when what concentration of volatiles are present?
>150 ppm
What type of fire extinguisher is used for grease fires?
Class B
How is the multiple tube fermentation technique for fecal coliform performed?
EC medium at an incubation temperature of 44.5 +/- 2 degrees celsius
What do you use before using pipets for phosphorous analysis?
HCl
What does MPN stand for?
Most Probable number
Who regulates confined spaces?
OSHA
What document is used daily to provide guidelines and directions for analysts and operators?
Standard operating procedures (SOP)
Meaning of TD & TC on glassware?
TD = to deliver TC = to contain
A single sample taken without considering time or flow is?
a grab
To assure greatest safety, how should all chemicals be stored?
according to manufacturers recommendations
What is the rule of acids and water?
add acid to water slowly and while stirring to disperse heat
how does activated carbon work?
adsorption
What is tested using the indicator methyl orange?
alkalinity
What is the nitrification cycle?
ammonia --> Nitrite --> Nitrate aka NH3 --> NO2 --> NO3
Potassium dichromate is an example of?
an oxidizing agent
Where should a sample be placed after a known volume of the sample is filtered for TDS?
analyzed immediately (in-situ)
Silver sulfate in COD analysis is used for what?
as a catalyst
When should sodium thiosulfate be added to the container for coliform samples?
before sterilization
cations are attracted to ...?
cathodes
What document follows all samples from collection through reporting and is filed with the test results?
chain of custody
how do you check a manhole for leaks?
check for gas coming out of edges before opening
main concern with a chemical spill is what?
clean up & containment
What is the correct method to prepare a total metals test after rinsing with tap water?
clean with nitric acid
Results of bacti test are expressed as what?
coliforms per 100 mL
What information should be on a sample?
date, time, initials
What is digestion?
decomposing a sample with high heat and acidic conditions
Jar test is for what?
determining dosage of polymer for coagulation and sedimentation
How do you prepare samples for metals analysis?
digestion
What term means killing pathogenic organisms?
disinfection
How do you reunite a liquid column of a thermometer?
dry ice - alcohol slurry and store vertical for 24 hours
What must be present for a bacti sample to fluoresce?
e-coli
Class "C" fire extinguishers are for what type of fire?
electrical
E. coli represents the presence of what?
fecal
Coliforms are indicators for what?
fecal microorganisms
the tss lab procedure uses what type of filter?
glass fiber
On what type of sample can oil and grease can be analyzed?
grab
In chemistry, what does the word Normality mean?
gram equivalent weights of reagent chemical per liter of solution
How often do you check eye wash and safety showers?
in intervals/monthly
How should chemicals be stored?
in the appropriate container as indicated
In the process of titration, phenolphthalein is used as an...?
indicator
The conductivity of de-ionized water should have how many microhmos/cm?
less than 0.2
Refrigeration at what temperature is the most accepted method of sample preservation?
less than or equal to 6 degrees celsius
What information should always be included on a sample label?
location, collection time, date, initials
What type of control curve should be used with graph paper?
logarithmic
What was the most common type of probe on a DO meter?
membrane electrode
Pre treatment of distilled water is important why?
minimize build up on equipment
What type of gloves are used in n-hexane analysis?
nitrile
TKN is comprised of what?
organic nitrogen and ammonia
digestion is the phosphorous test that produces what?
orthophosphates
Nitric acid (NO3) is an?
oxidizer
type 1 reagent water is distilled then to make it better it is ...?
passed through a mixed bed then through a 0.2 micronmeter filter
What is the titrant for amperometic titration of chlorine?
phenylarsine oxide (POA)
What kind of container is acceptable for an ammonia sample?
plastic or glass
The reproducibility of a method when repeated on a homogenous sample under controlled conditions is what?
precision
Coliform are indicators for?
presence of microorganisms
Why use a water bath to incubate fecal coliform?
provides a consistent temperature
If an analyst breaks a control point what should they do?
reanalyze
What to do with containers that contain magnesium and/or other metals?
rinse with nitric acid
What type of graph paper is used for ammonia/fluoride control curve?
semi-logarithmic
Primary concern when buying buffers?
shelf life/ expiration date
What chemical makes water more alkaline?
sodium hydroxide
What is added to a bacti bottle to remove chlorine?
sodium thiosulfate
Bottles used for bacti sample collection should be ...?
sterilized
What are waste management methods?
the 3 "r"s - reduce, reuse, and recycle
In the lab, what does the term buffer refer to?
the action of certain solutions in opposing a change of composition, especially of hydrogen ion concentration
Why do you have to analyze CL2 residual samples immediately?
to avoid dissipation
What is the purpose of the jar test?
to calculate dosage of polymer
Why do you use sodium thiosulfate in chlorinated samples?
to dechlorinate the samples
A desiccator is used for what?
to maintain a certain dryness (dry environment)
Why is sodium thiosulfate used?
to prevent interference from chlorine
Why should a chlorine residual be maintained in a water system?
to protect the bacti quality of the water
What do you use when you make a standard?
volumetric flask/pipets
What happens in COD analysis when you homogenize the sample?
you make it uniform/similar
