PMSA Conference

Heger, Sampling

1/20/2014

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Sara HegerUniversity of Minnesota

Pathogens Confined space Power

Bacteria- can cause diarrhea, fever, cramps, vomiting, weakness, or loss of appetite. ◦ Examples-E.Coli, Salmonella, cholera

Parasites- can cause coughing, breathing difficulties, abdominal pain, and intestinal blockage◦ Examples-Giardia, Cryptosporidium, helminths (worms)

Viruses- can cause tiredness, abdominal pain, nausea, and diarrhea◦ Examples-Hepatitis A

Oral-hand to mouth contact during eating, drinking, and smoking. Or by wiping your face with contaminated hands or gloves. (major source of infection)

Dermal-skin contact from wastewater splashes. Having cuts, scratches, and wounds raise the risk.

Eyes-pathogens can enter the body through the eyes

Lungs-inhaling airborne microbes carried by dust, mist, or fumes.

Respiratory exposures All of the tools touched Truck door handle Steering Wheel Radio Gear shifter Lunch Cigarette, gum, etc.

PMSA Conference

Heger, Sampling

1/20/2014

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Vaccinations for typhoid fever, tetanus, paratyphoid, polio, hepatitis

Use of waterless hand cleaners, anti-bacterial soaps, hand wipes

Clean implements (soil auger, paddles, sludge/scum tubes, hand tools for opening riser covers)

First aid kit

Wear latex or rubber gloves Wipe down surfaces (steering wheels,

gearshifts, door handles, door tools) with disinfectant

Keep hands and fingers away from mouth, nose, eyes, ears

Separate work clothes from personal ones Soak work clothes in hot water with chlorine

bleach

Meet all requirements TRAINING: Certification Lifting equipment◦ Harness◦ Partner

Testing

Dissolved Oxygen pH Temperature Sludge volume Settlability Odor Turbidity

Concentration of O2 dissolved in water◦DO low in septic tank <0.3 mg/L◦DO >2 from advanced units

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1/20/2014

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Concentration of O2 dissolved in water◦ Measure with meter and probe or colorimetric

kit◦ DO expressed as mg/L ◦ negative log of hydronium ion

concentration◦ measure with pH meter, an

electronic device with probe◦ pH of domestic wastewater ranges

from 6.5 to 7.5◦ rapid changes can kill bacteria

• Measures acid or base quality of water

High◦ Fats

Temperature◦ < 75o

Low◦ Nitrogen◦ < 50o

◦ Bacteria◦ < 40o

Tank performance◦ Full at 25-33 %

Scum- Scum hook Sludge-◦ Sludge judge◦ Dipstick◦ True-Core

ATU: Settle-ability◦ Later

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Heger, Sampling

1/20/2014

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From Aeration chamber of ATUs

30 Minute Settlability Test◦ Beaker with 10 even

gradations◦ Fill beaker with

sample from aeration chamber.

◦ Let stand for 30 minutes and read level of clear zone.

20% to 60% is ok.

Turbidity is the cloudiness or haziness of a fluid caused by individual suspended solids that are generally invisible to the naked eye similar to smoke in the air

The measurement of turbidity is a key test of overall water quality

BOD5◦ Biochemical oxygen demand◦ 5 day test of how much oxygen is used breaking

down organic material present in sample◦ < 170 mg/l is a typical home◦ Higher the number the dirtier the wastewater is◦ Bacteria in the soil or treatment unit eat up the

organic material while consuming oxygen

PMSA Conference

Heger, Sampling

1/20/2014

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Amount of oxygen consumed by microbes during decomposition of organic matter

Indicates overall organic strength of wastewater

High BOD means high levels of organics Expressed in mg/L Raw Domestic wastewater ranges from

100 to 400 mg/L BOD

Measurement of change in DO concentration in samples over a given period of time at a specified temperature

Standard test is 5 days at 20oC (BOD5)

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Volume > 100 ml Bottles Plastic, Glass Preservation Storage Cool, 4°C Timing 48 Hours

Amount of organic matter oxidized by a strong chemical oxidant◦ also oxidizes additional compounds that

microorganisms don’t decompose◦ COD values always greater than BOD values◦ COD can be used to estimate BOD if BOD:COD

ratios are developed◦ COD tests take 3 to 4 hours

Samples digested with sulphuric acid and chromium and silver salts

Results colorimetrically analyzed Expressed in mg/L

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1/20/2014

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Volume > 100 ml Bottles Plastic, Glass Preservation Storage Cool, 4°C Timing 48 Hours

FOG◦ Fats, Oils, & Grease◦ Fats are animal based and solid at room

temperature◦ Oil are vegetable based and liquid at room

temperature◦ Grease is burnt fats and oils Petroleum-based FOG industry/automotive repair not readily broken down by microorganisms

◦ Typical home is <25 mg/l

Volume > 100 ml Bottles Glass Preservation HCL or HSO4 pH<2 Storage Cool, 4°C Timing 28 days

Total suspended solids (TSS)◦ sample filtered through pre-weighed filter◦ filter and residue dried at 103 -105oC◦ increase in weight of filter represents TSS

Total dissolved solids (TDS)◦ filtered sampled dried in pre-weighed dish at

180oC◦ change in weight of dish represents TDS

TSS◦ Total suspended solids◦ Measures both organic and inorganic

solids which have not settled out (polyester, dirt, etc)◦ Typical home is <60 mg/l◦ Effluent filter in septic tank can reduce but

really just keeps it constant

PMSA Conference

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1/20/2014

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Volume > 100 ml Bottles Plastic, Glass Preservation Storage Cool, 4°C Timing 7 days

Indicator organism ◦ cultured in standard tests to

indicate contamination◦ membrane filter technique direct count of colonies trapped and cultured◦ multiple tube fermentation method provides an estimate of the MPN per100 ml◦ measured as colonies/100 mL

Volume > 100 ml Bottles Plastic, Glass Preservation 0.008% Na2S2O3 Storage Cool, 4°C Timing 6 Hours

Organic N◦ found in cells of all living things

(proteins, peptides, amino acids)◦ principle compound in feces and urine 70% in Urine◦ Converted in septic tank to ammonium

Ammonium N (NH4+)

◦ positively charged, binds to soil particles◦ converted to NO3

- in aerobic conditions ◦ Primary form of nitrogen leaving a septic

tank

Nitrate N (NO3-)

◦ stable over a wide range of conditions◦ negatively charged, not held by soil◦ high potential for leaching to groundwater◦ converted to N2 in anaerobic conditions◦ primary for of nitrogen after secondary

treatmentNO3

-

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1/20/2014

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TKN Volume> 100 ml

BottlesPlastic, Glass

Preservation Storage

Cool, 4°C Timing

48 hours

Nitrate Volume> 100 ml

BottlesPlastic, Glass

Preservation Storage

Cool, 4°C Timing

48 hours

Alkalinity is the quantitative capacity of water to neutralize an acid

Mainly a measure of how much carbonate in the water

Key for nitrogen removal

Volume > 100 ml Bottles Plastic, Glass Preservation Storage Cool, 4°C Timing 14 days

Found in body wastes, food residues, fertilizers, detergents, industrial discharges◦ Primary & secondary orthophosphates (H2PO4

- and HPO4

2-) - forms available to plants◦ P in soil often forms insoluble compounds◦ Rarely mobile in soil, but can move with soil particles

during erosion◦ Typical level is 8-12 mg/l

Volume > 100 ml Bottles Plastic, Glass Preservation Storage Cool, 4°C Timing 48 Hours Volume

Inorganic chemical compounds ◦ often found in industrial discharges◦ stable and resistant to decomposition◦ some essential for animal & plant nutrition ◦ at higher levels some can be highly toxic◦ in soils, solubility increases as pH decreases

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Stable organic compounds◦ slow to decompose◦ can persist in soil and groundwater for years◦ many are synthetic compounds industrial discharges solvents & household cleansers paint medical products

Volume > 100 ml Bottles Glass Preservation Storage Cool, 4°C Timing 28 days

Sample purpose Analysis methods Timing of sampling Sampling location Sample collection Sample containers Sample volume Sample transport Laboratory Interference

Diagnostic - troubleshooting Performance - evaluating system Can be collected for a specific component

diagnostic Effluent sample for overall system

performance Meet regulatory performance standards

Representative Reproducible Defensible Useful

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Freshly flowing versus processed water

Peak loading time vs Resting period

Depends on materials◦ BOD ◦ Solids◦ pH

w/in 18 hrs of peak Lab hours

Sample collected on a Thursday, temperature on the left is appx 85° and temperature on the right is 76°

Sample collected on Saturday afternoon, temperature on the left was appx 76° and temperature on the right

was appx 102°

Sample collected on a Saturday afternoon,

temperature appx 102° Temperature has dropped to appx 95°

What are you sampling?◦ Influent◦ Effluent

Where in the system

Influent samples are collected from the beginning of a component.

Effluent sample is collected from the outlet of a component.

Influent

InfluentEffluent

EffluentEffluent Influent

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Grab Sample- One sample taken from one point and time◦ Gives an idea of what is happening right then

Composite-◦ Multiple samples taken from one point at

multiple times and integrated together for analysis ◦ Pulled from a location that provides a composite.◦ Multiple grab samples at different flow periods.◦ Averaging over the course of a day

One time One location Snapshot

May change through out:◦ Time◦ System

Over time◦ Take grabs related to: Time Flow◦ Mix the samples for an AVERAGE

Over the System◦ Take grabs related to: Area/ Volume◦ Mix the samples for an AVERAGE

Grab sample with composite sample characteristics

Selecting right tool for the job.◦ Sludge judge◦ Dip Stick◦ Sample bottle◦ Dipper◦ Vacuum pump

Use clean collection equipment

Collect from “cleanest” end first

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Depends on test Process

performance Best – external

sampling port Outlet baffles Discharge from

system Consistency

Pressure Distribution - Pump tank Gravity System - Outlet of the septic tank Propriety System - Use manufacturers’

recommendations◦ ATU ~ DO: Out of the unit

NOT usually from beneath systems

Types of Containers◦ Glass◦ Polyethylene

Test specific Check with laboratory Clearly label the

sample container with water proof markings

Water tight

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There are requirements that need to be followed for standard method testing:◦ Sample Container◦ Preservation◦Maximum holding time

Biochemical oxygen demand (BOD)◦ Container- Polyethylene or Glass◦ Preservation- 4°C (ice)◦ Maximum holding time- 48 hours

Oil and Grease (FOG)◦ Container- Glass◦ Preservation- 4°C and add HCL or H2SO4 to pH<2◦ Maximum holding time- 28 days

Fecal Coliforms◦ Container- Polyethylene or Glass◦ Preservation- 4°C and 0.008% Na2S2O3

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◦ Maximum holding time- 6hrs

Temperature◦ Container- Polyethylene or Glass◦ Preservation- None◦ Maximum holding time- Analyze immediately (within 15 min)

Test Dependent Rule of thumb◦ Quart

Check with laboratory More tests = More

sample Cleaner water = More

sample Fill the container

Lab requirements

Container Timing◦ How long the

sample lasts ‘Immediately’

means with in 15 minutes

It is in your actual physical possession It is in your view, after being in your physical

possession It was secure beyond a reasonable doubt if

not in your view

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1/20/2014

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Ice Chest w/ ice Check with lab for

constraints on analysis

Maximum holding time◦ Test must be started

w/in the time requirement

Document COC

Testing methods Data Range◦ Non-detection◦ Greater than X◦ Too numerous to

count Standard methods Purpose of the data Lab accreditation◦ Check for specific

test

Standards in the Operating permit Good values◦ Flow◦ Parameters

Bad values Re-sampling◦ What does this mean◦ Who pays

How good is your data (sample)?

Chemical◦ Contaminants in waste

stream◦ Disinfectants◦ Person collecting sample

Solids◦ Scum◦ Debris on baffle

Containers Improper handling◦ Transport

sheger@umn.eduwww.septic.umn.edu