lab analyst i/ii cwea

Celcius

Fahrenheit

(F-32)5/9

(C+32)9/5

HPC
water media bath

time for incubation and temp

unit

45C 3 hrs hold time

48 ± 3hr at 35 ± .5C

CFU/ml

Precision

a measurement of how close a series of measurements are to one another

Accuracy

how close a measurement is to the true value

Electrical Fire

Unplug and sodium bicarbonate

Analytical Balance

A device for determining mass that gives highly accurate measurements

Top loading balance

used to determine mass; not as precise as an analytical balance

Triple beam balance

instrument used to measure mass, less sensitive than top loading

Coliform characteristics; gram? shape?

E Coli is an indicator organism because..

gram-negative, rod shaped bacteria present in intestines', includes E coli and other sp

indicator because the presence indicates conditions are right for harmful bacteria

Always add - to -

Acid to water

Spectrometer definition

UV/Visible spectroscopy is based on what principle?

In atomic absorption, atoms must be x to absorb light at its characteristic wavelength

a device that spreads light into its different colors

Beer’s/Lambert’s law; absorbance is proportional to concentration

reduced to their ground-state

rounding off

.5 = keep, <.4 same, >.6 round up

sig fig rules

use the smallest amount of decimal places;

non zero digits always sig

any zeros b/t sig digits are sig

trailing or final zero in decimal portion only are sig

BOD

total =

vol, bottle, temp, time

storage ph? pretreatment?

method

If DO present, what color will floc turn after alkaline iodide-sodium azide solution is added? No DO?

what colors during titration?

formula?

after 5 day incubation, BOD sample should have a DO depletion of at least? and blank should never exceed?

CBOD, 2-chloro-6-trichlormethyl pyridine (TCMP) suppresses

if >9.0 mg/L DO at 20C, you should

what sugar compound used?

units

interferences

calculation for seeded & unseedd

total = Carbenous, soluble, nitrogenous

1000 ml, p/g, 4C, 48h

neutralized 6.5-7.5, dechlorinated residual Cl, .025 N sodium sulfite

method

5 d 20 ± 1C incubation ±6h

brown with DO, white w/o DO

brown → straw yellow → blue → clear

(DOi-DOf)/(sample vol/bottle vol)

take 2.0 mg/L, leave 1.0, blank must not deplete more than 0.2 mg/L DO

(carbonaceous BOD) suppresses nitrification

agitate or aerate the sample at 20C

glucose

mg/L DO

interferes with algae, probe membrane…bio based test cannot control all variables

sample labels should include

sample number, sample type, name of collector, date/time of collection, place of collection, and sample preservative

mg/L to lb/day

feed rate (lb/day)=dosage(mg/L) x flow rate (mgd) x 8.34

composite sample

collection of indiviual samples obtained at reguular intervals based on flow or time (combined porportionally)

grab sample

sample taken from a waste stream without regard to flow, over a period of time not to exceed 15 minutes

COD CHEMICAL OXYGEN DEMAND

summary

vol, bottle, acidify and temp, time

standard?

method? 

1. open

2. closed

what is wrong with a COD sample turns green in reflux?
wavelength spec

calculation

units

haz waste produced

interferences

COD=BOD=TOC Correlation?

Dichromate ions oxidize organics in sample to produce chromic ions Cr3+

50 ml, p/g, h2so4 to ph<2, 4c, 7 days

std: potassium dichromate K2Cr2O7/potassium acid phthalate

method

Open: K2Cr2O3 and titrated with FAS blue green to red brown

Closed: dichromate oxidized ferrous ions, blue green to red brown

(ferrous ions no longer oxidized by dichromate, phenathroline forms red complex. takes end point to first sharp color change blue green to reddish brown)

all oxidizer has been depleted

wavelength spec

0-150 mg/L = 420 nm

150-1500 mg/L = 620 nm

((blank-sample)(M)(8000))/mL sample

mg/L

haz: Hg, hexavalent chromium, silver

interferences: volatile organics (fix:silver sulfate), halides (fix:mercuric sulfate)

COD=0.5*BOD=1.2*TOC

TURBIDITY

collection & storage?

units

lamp, cuvette, wavelength, what angle?

100 ml, p/g, 4±2c, 48 hrs

NTU; nephelometric turbidity unit

tungsten-filament, 10<cm cuvette, 400-600 nm, 90 degree

Total Suspended Solids TSS

def

vol, bottle, temp

hold time

solids left on filter

100 ml, p/g, 4C

7 days

Total Dissolved Solids TDS (residue filterable)

def

vol, bottle, temp, time holding

bake at x temp and dry at x temp?

solids that pass thru filter size 2.0 um

100 mL, P/G, 4C, 7 days

bake at 103-105C, dry at 180±1C

TS hold time

7 days

VS hold time

7 days

ACIDITY

definition

collection & storage

pretreatment?

method?

measures what and with?

Indicators used and pH

report as, and what EPA endpoint?

interferences

calculation

acids influence reaction rates, chemical speciation, and biological processes. CO2 is most likely cause of acidity

100 ml P/G 4C 24 hr

0.1 M NaS2O3 sodium thiosulfate

strong base required to bring sample to designated pH, using 0.02 N NaOH sodium hydroxide, with stir bar

Indicators

1. pH 3.7 bromophenol blue (yellow to blue)

2. pH 8.3 metacresol purple (red acid-yellow neutral-purple basic) OR phenolphthalein

report as mg/L CaCO3 and include specific pH endpoint, per EPA
interefences

1. Chlorine as it may bleach the indicator (no color change)

2. dissolved gasses lost (avoid vigorous shaking)

3. turbidity/color

mg/L = (titrant used x N NaOH titrant x 50000)/sample vol mL

ODOR

collection and storage?

volume?

method temp

unit

Glass only 4C 24 hrs

200 mL

erlenmeyer flask 60C water bath

Threshold odor number TON

Settable solids hold time

48 hrs

COLOR

collection & storage?

APPARENT

vol in what tube?

TRUE

wavelength?

BOTH

unit?

glass or plastic, 48hrs, 4C

50 mL nessler tube-apparent

455-true color

both in CU units

cl residual hold time

15 min

CHLORIDE

collection & storage

2 methods prevalent, and titration, std, x and x

interferences?

50 ml g/p 28 days

1. argentometric method: titrate AgNO3 with indicator chromate ions w/ end point reddish silver chromate

2. mercuric nitrate method: titrate mercuric nitrate b/t ph 2.3-2.8, indicator diphenyl carbazone w/ end point blue to purple in presence of mercury

3. ion chromatography

interferences: iodide, bromide

Chlorine

purpose

collection & storage?

Cl residual is commonly performed as __

Methods & Reagents (2 Iodometric, 1 Amperometric, 1 Titrimetric)

What 2 solutions should be added to the sample?

What are the methods, include indicators.

How many mL of sample should be analyzed?

With a spectrophotometer, what wavelength?

Why mercuric nitrate titration technique falling into disuse?

calc

interferences?

to destroy or deactivate disease-producing microorganisms

200 ml, p/g, immediate (within 15 m)

Amperometric titration

Method

KI (potassium iodide) and acetate buffer (KI)

1. Iodometric: Starch indicator, KI & sodium thiosulfate at pH 3-4. yellow to blue color change

2. Iodometric:reducing agent (PAO or thiosulfate) and titrate with iodine with KI & buffer. used to back titrate iodine

3. Amperometric titration: PAO w/ KH2PO4. indicates with smaller deflection response

4. Titrimetric: DPD indicator w/ FAS titrant, phosphate buffer

200 mL

515 nm

mercury disposal

sample titrated±blank(N)(35450)/mL sample

Interferences are turbidity/color, DPD with Mg

Standard phenylarsine oxide solution

PAO should be handled with caution because it is a severe poison

Sample protocol for chloride

glass or plastic container, no preservative

during acid-base titutaion, the titrant is added to the sample with

buret

seperatory funnels for liquid-liquid extractions, used to seperate

organic analytes from water by partitioning them into an organic solvent

pH

definiton

collection & storage

temp/ph relationship; hold time

temperature for titration

solution with pH of 5 is how many times higher than pH 7?

what buffer is a control of ph 7?

bromcresol green indicator has pH endpoint

calc

measure of hydrogen ion activity at a temperature

25 mL p/g, immediately (15 m)

temp rises, ph drops; must measure pH within 15 minutes of collecting sample

25C ± 2C

100x

KH2PO4/Na2HPO4

4.5

ph=-log[h+]

CONDUCTIVITY

definition

collection & storage?

volume

standard solution

Temperature is compensated to -

report temp at

Interferences

unit

range for DI water?

range for potable water?

ability to carry a current

p/g 28d 4±2C

100 mL

0.01M KCl Solution

25.0 C
25.0 ± 0.1C

temperature is an interference

uS/cm=umhos/cm

DI: 0.5-3 umhos/cm

Potable: 50-1500 umhos/cm

ALKALINITY

definition

collection & storage?

indicators used and ph? (4)

acid titrant standardized with

units?

interferences

calculation

acid-neutralizing capacity of water

100 ml, p/g, 4± 2C, 14 days, minimize airspace to reduce CO2 from atmosphere

1. bromcresol green or methyl red to 4.5 pH

2. metacresol purple or phenolpthalein 8.3 pH

3. 0.1 N or 0.02 N H2SO4 or HCl to 4.5 pH

4. starch + iodine (ends in blue)

Na2CO3 sodium carbonate

alkalinity, mg CaCO3/L

interferes with soaps, oils, solids

mg/L= (vol acid titrant x normality x 50000)/sample vol mL (same as acidity)

HARDNESS

EDTA Titration

collection & storage?

how long after buffer addition should titration be completed?

EDTA titration determines -

max EDTA titrant used for volume sample

Indicator used is - and pH

calculation

interferences

units

plastic/glass acidify with HNO3 to pH <2.0 with max hold 6 months, 100 mL

5 minutes

calcium and magnesium

15 mL

eriochrome black T, red to blue at pH 10 ±.1

(mL titrant)(mg CaCO3 equiv to EDTA)(1000)/mL sample

interferes with metals or organic matter

mg/L as CaCO3

total coliform group definition

aerobic, facultative anaerobic, gram negative, non-spore forming rod shaped bacteria that ferment lactose in 24-48 hrs at 35C

bias

to be accurate, bias must be

consistent deviation of measured values from the true value caused by systematic errors in a procedure

accuracy = low bias and high precision

random error

combination of bias and precision of an analytical procedure, which reflects the closeness of a measured value to a true value

SETTABLE SOLIDS

def

vol, bottle, temp, hold time

mixed liquor test, why is a setteleometer preferred over 100-ml graduated cylinder?

during testing, seperation of settable and floating may occur, in such only report

during testing, if settled materials develops pockets of liquid between large settled particles

SS may be determined

by volumetric method, summarize procedure

Imhoff cone used for

solids left on filter

1000 mL, P/G, 4C, 48hrs

sideall effects of narrow; wider is better at simulating a secondary clarifier

only report weight or volume of settled

estimate volume of liquid pockets and subtract from total volume of settled solids

on gravimetric basis, reported as milligrams/liter

record level of settled solids after 45 mins, gentle agitate, then 15 mins of additional settling

ml/L

MLSS is important for mixed liquor suspended solids

calculating MCRT mean cell residence time

SLUDGE SAMPLES

method: instrument, vol, time, unit

centrifugation provides

good quality indication

SVI calculation (sludge volume index)

imhoff cone, 1L, 45 min, agitate, 15 min, record mL/L

concentration by volume

brown color, musty odor

SVI=(setttleable sludge vol)x(1000)/suspended solids

DISSOLVED OXYGEN DO

units

membrane/optical probe

vol, bottle, time

DO readings taken at time intervals no less than

method for field testing WW?

interferences

azide-winker/idometric

vol, bottle, time

reagents

what modification of winkler test is for biological floc with hi oxygen utilization rates?

what is the hold time for acidified winkler method sample?

removes what?

white floc indicates?

color change?

Interferences?

pheno

vol bottle time

idometric color change?

mg/L DO

membrane/optical probe

300 ml, g only, immediately

1 minute

membrane electrode method electrometric b/c fewer interferences

interferences: algae and oil

azide-winker/idometric

MnSo4, alkali-iodide, indicator starch w titrated 0.025 sodium thiosulfite (1-1) or potentiometric

300 ml, g, fix and dark, 4-8h

sulfamic acid floccation

8 hrs

removes nitrite, when floc white = no O2

brown to straw to blue to colorless

Interferences: NO2-N (Nitrite nitrogen), Ferrous iron, suspended solids

pheno

500 ml, g, 4c h2so4 to ph<2, 28 d

blue to straw to blue to colorless

it is most important parameter for WW biological activity

DISSOLVED SOLIDS

also known as

bottle

temp to hold

time to hold

EPA method for determination

theoretical concentration calculated by

filterable residue

glass or plastic

4C

7 days

well mixed sample filtered thru glass fiber, evaporated, dried at 180C to constant weight

total solids conc - SS conc of same sample

prep glass fiber filters

Place filter on gooch crucible, apply suction

rinse 3× 20 mL of DI water, with suction

handle filters with forceps or tongs

TOTAL SUSPENDED SOLIDS

defined as

procedure for dry, cool, weigh?

constant weight defined as

reduce volume size if filtration time exceeds

also known as residue, nonfilterable

EPA, minimum residue on 4.7 cm filter

material retained after passing sample thru glass fiber filter 2 um

104C ± 1Cdry at least 1 hr, cooled in desiccator, and weighed

weight difference of ± of less than 0.5 mg

5-10 mins

1.0 mg

TOTAL SOLIDS

vol, bottle, temp

are defined as

determined on evaporation procedure

per EPA, samples should contain residue of atleast

100 mL, P/G, 4C

sum of TSS and DS

oven at 98C, then 1 hr 103-105C, cool in dessicator

25 mg

prepare clean evaporating dishes for total residue

heating dry oven 103-105 for 1 hr, store in dessicator

TOTAL VOLATILE SOLIDS TVS

vol, bottle, temp hold, time

TVS represents weight of material lost

muffle oven set temperature

FS vs VS

100 mL p/g, 4C, 7 days

after burning TS 550C

550C ± 50C

solids left after high heat FS fixed

solids lost after high heat VS volatile

ash content of a sample is same as

fixed residue

NaOH stored in

polyethylene bottle

TC means

to contain

Fritted glassware is

porous

Beakers used for

mixing chemicals

pipets used to deliver one specific volume are

and should not?

volumetric pipets

not be blown out

what purity grade for general lab use?/

analytical reagent grade

all anhydrous reagent chemicals for standards and titrants must be prepared before use by

drying in oven 105-110C for 1-2 hrs or overnight, then cooling to room temp in desiccator

distilled water prepared by

borosilicate glass, fused quartz, tin, or titanium still

when reading a meniscus of a buret, bring eye to level to avoid

parallax errors

desiccator purpose

prevent moisture

microbuuret graduated in

hundrenths of a mililiter

ambient temp affects volumetric glassware, solutions should be measured at what temp

20C (1000mL of water increases 0.2 mL per 1C rise)

to clean inorganics on glassware use

strong acid

Multiple-Tube Fermentation MTF for Coliform

density estimated reported as

lauryl tryptose broth or BGB confirmation of coliform is

ltb ph

bgb ph

general set up?

total coliform

dilution steps

3 tests phases w/ incubation temp, time, and media

MPN Most Probable Number is for

Multiple-Tube Fermentation MTF for Enterococcus

enterococcus positive is

MPN/100 mL

gas bubbles

ltb 6.8 ± .2

bgb 7.2 ±.2

series of tubes with 10xmL dilutions: 10 tubes 10 mL or 5 tubes 20 mL

total coliform:

10, 1, .1 mL

presumptive, confirmed, completed

P: LTB, 24h ± 2 then 48 hr ± 3 for gas 35C ± .5

Cn: BGB 48 ± 3 hr 35C ± .5 for gas

Cm: QC 20%; EC broth 44.5 ±.2 C, 24 ± 2hr for gas and acid

autoclave 121C for 15 mins to sterilize during completed

quanti-tray

Multiple-Tube Fermentation MTF for Enterococcus

P: azide detrose broth, 24h ± 2 then 48 hr ± 3 for turbidity 35C ± .5

Cn: BEA 24h ± 2 at 35C ± .5, brown-black with halo for pos and

BHI with NaCl & w/o

for bacteriological examination, Na2S2O3 used to

is it used in coliform?

neutralize any remaining disinfectant

yes

Membrane Filter MF for Coliform

filter size

incubation temperature

total coliform desired density per membrane

fecal coliform desired density per membrane

used because..

Membrane Filter MF for Enterococcus

filter and density desired

incubation for 3 methods and times

filter 0.45 um

44.5C ± 0.2C

20-80

20-60

used because it is highly reproducible, can test large volumes, more rapid numerical results

Membrane Filter MF for enterococcus

filter 0.45 um for 20-60

me and mEI methods incubate at 41 ±.5C for 48H or 24H, corresponding

mEnterococcus at 35± .5C for 48H

For micro, sterilize glassware by oven at

170C for at least 1 hr

Desired range of coliform colonies on plate?

20 to 60 CFU/100 mL

For microbial sterilization, in an autoclave:

Temperature, time, lbs of pressure?

dry heat?

How soon should media be placed into an autoclave after prep?

How soon should MTF tubes be removed?

autoclave 121C for 15 mins at 15 lbs pressure

>170C for 2 h or longer

glassware for 121C for 30 mins

Within 2 hours

Within <45m

Fecal coliform characteristics

and as a pathogen indicator

non spore forming, rod shaped, gram negative

as indicator, greater numbers than pathogen, in mammals intestinal tract, not pathogenic

TOXICITY

single conc set up with replicates for 24-96 hrs known as

screening test with LC50 as single endpoint

assess toxic effects at life stages or repro

most challenging for hi BOD or COD or hi bacterial cfu

the conc to produce death in portion of organisms is

test where organisms exposed to solutions of same composition and replaced periodically is called

lowest dose for statistical sig dif from control

screening test

acute test (shows short term toxicity)

chronic test

static test

LC lethal concentration

renewal test

LOEC lowest observed effect concentration

What conc Na2S2O3 sol is used to dechlroinate WW for micro testing?

Buffered diluted water for bacteriological exam is added to 1 L has

10%

1.25 KH2PO4 monopotassium phosphate and 5 mL MgCL2 magnesium chloride

Coliform color

fecal on M-FC

total on M-endo

blue

gold-green sheen

QC

control chart, includes

Out of control looks like’

verify control chart

to calculate geometric mean, measurements must be converted to

std deviation is

good program has

values above the highest standard should not be reported unless

date, method, lab name, parameter, unique info ie conc, analysis ID NOT required reagents

points beyond limits

68% of data fall within interval P±Sp distrubution

logarithms

sq root of varience

certs, recovery of known additions, analysis of external supplies, analysis of reagent blanks, calibration w standards, analysis of duplicates, and control chart maintenance

initial demo of greater linear rangeg, no parameters changed, and the value is fewer than1.5x highest standard

QC

to determine matrix effects,

how many minimun calibration standards should be used when an analysis is inititated?

addition of known material values should be

how many std dev are warning limit from avg?

control limit on control chart is how many std dev?

do known additions

three

one and 10x ambient level

2

3

What is the referred doc for sample preservation?

40 CFR 136

NITROGEN - TKN

collection & storage?

total kjeldahl method determines

kjeldahl method, in distillation, the sample is buffered to

what method for analyzing nitrate nitrogen?

500 ml, p/g, 4c, H2S04 to pH <2, 28 days

sum of ammonia and organic nitrogen (determines nitrogen)

9.5 pH

cadium-reduction

most oxidized form of nitrogen in w and ww

during nitrification, nitrobacter and nitrsomonas do/do not require oxygen?

nitrate

during nitrification, the bacteria require free molecular oxygen

NITROGEN - AMMONIA

collection & storage?

Ion-Specific Electrode method

range

uses how much sample and std?

method

Phenate Method

range

interferences

color change

what wavelength is used?

prep with ? distil with?

Distillation & Titration

prep with ? and distil with ?

range for titration

titrate with ?

color change

500 mL, p/gm 4C, pH 2 using H2SO4, up to 28 d

Ion Specific

0.03 - 1400 mg/L

100 mL,series mg/L ammonium chloride

pH >11 to convert NH4+ to NH3

interferes with amines, Hg, Ag

Phenate

10 ug/L- 500 ug/L

develops intensely blue

640 nm

dechlorinate with sodium thiosulfate

distill into H2SO4 acid (phenate)

Distillation & Titration

dechlorinate with sodium thiosulfate

distil into Boric acid (titration)

>5mg/L

titrate with sulfuric acid

blue/green to pale lavender

PHOSPHORUS **

vol, bottle, temp, preserv(?), time of:

ortho, hydrolyzable, total, TD

indicator

acid digestion of total phosphorus results in

total phosphorus defined as

ortho: 50ml, p/g, filtered 4c, 48 h

hydro: 50ml p/g 4c H2SO4 to ph<2, 28 d

total: 50 ml p/g 4c H2SO4 to ph<2, 28 d

TD: 50ml p/g 4c, filtered, H2SO4 to ph<2, 28 d

phenolphthalein

release phosphorus as orthophosphate

defined as reactive(large portion of ortho-), acid-hydrolyzable(“condensed” ortho-), and organic (only ortho after destruction)

what temperature is at greatest density?

the density is?

4C

1.000 g/cm3

fume hood air flow?

how many room air changes?

chemical hygiene plan should be reviewed?

100 linear ft per min

4-12 changes per hour

annually

flow

dosing

volume

flow cu ft/sec = area sq ft x velocity ft/sec

dose mg/l= chemical feed lbs/day / (flow, mgd x 8.34 lbs/gal)

vol cu,ft =

cone 0.33 x pi x d x h

cylinder/circle pi x d x h

rectangle l x w x h

percent

g/100g or %/100%

solids storage

all, plastic glass, 4C

only settable 48 hrs

rest 7 days

normality

molarity

equivalent weight = molecular weight g/mole / equivalent number

N= weight substance/(equivalent weight of substance)(L of solution)

M = mol/L, n= # of H or OH

N1 V1 = N2 V2

Relative percent difference RPD

(R1-R2)/((R1+R2)/2)

COLIERT

incubation time

temp

results

presence/absense of coliform

incubate 24 hrs + 3

35C ± .5

clear to yellow = total OR yellow/fluorescent = e coli

then count MPN

Micro Transportation

generally, per SM

<10C, kept cool in dark nondirect ice pack

compliance

DW

SW

<10C if longer than 1 hr from collection, not frozeen

DW 30 hrs collection to analysis (8 hr for HPC)

SW 8 hrs (6 hrs transit) (sludge is 24 h)

Other <24h

4 hrs apart on checking

TEMPERATURE

vol, bottle, hold time

1000 mL, p/g, immediately within 15m

What are the 3 classes of fire extinguisher?

Class A: General

Class B: Grease

Class C: Electrical

Class D: Combustible metals (ie, Mg)

Anaerobic digestor pH?

alkalinity?

6.8-7.2

1500-5000 mg/L

CALIBRATION

pH meter: frequency & with how many points?

Turbidimeter: frequency & what content?

Conductivity meter: frequency & what content?

Thermometer: Water batch increments of C and against?

balances: check x and x, frequency?

pH meter: daily, 2 points but begin with 7

Turbidimeter: daily, formazine only

Conductivity meter: monthly, 0.0100 N KCl standard

Thermometer: 0.5C, NIST

balances: check 0 and 2 weights daily

CONVERSIONS

1 L is equivalent to

1 oz is equivalent to

1 Quart

1 gram

INITIAL DEMOSTRATION OF CAPABILITY (IDC)

Performed when,

What and how many QC elements are involved?

ONGOING DEMOSTRATION OF CAPABILITY (ODOC)

Also known as

Acceptance percentage

METHOD DETECTION LEVEL (MDL)

How many to analyze? Over what time? Acceptance range?

IDC

New operator, new instrument

1 Blank, 4 LFB @ 10x MDL & midpoint of curve

ODOC

Laboratory Fortified Blank (LFB)

10%, may need to be from secondary source

MDL

7 samples, over 3d period, within 1-5x range

What are the OSHA limits for exposure to hazardous substances?

PEL; Permissible Exposure Limit

TLV; Threshold Limit Value