Field (final)

Question 1

Why is field analysis necessary?

Answer 1

Because the nature of any sample will change as soon as it is removed from its original environment

Question 2

What are some field measurements

Answer 2

• temp
• pH
• conductivity
• DO
• turbidity
• residual chlorine
• HC vapour
• immunoassays

Question 3

What are most field measurements dependant on?

Answer 3

Ambient barometric pressure

Question 4

What are some field quality control activities?

Answer 4

• collecting representative samples
• appropriate equipment
• proper handling and preservation
• proper chain or custody and preservation
• proper QA and QC
• field equipment (calibration, documentation,)
• document name, model, serial number, method of calibration, instrument response, date and time, solutions and concentrations and results of QC solution

Question 5

Are immunoassays cost effective?

Can they be used both qualitatively and quantitatively?

How many samples can be measured in an hour?

Answer 5

Yes

Yes

20-30

Question 6

How does immunoassays work?

Answer 6

It’s used the natural response of an organism to a foreign material as the mechanism for detection and measurement.

Biochemicals (antibodies) are used to detect and/or measure environmental pollutants

Question 7

What is the general process observed in immunoassays

Answer 7

1) sample added to tube coated with an enzyme catalyzed antibody
2) antigen added (env pollutant testing for)
3) antigen and pollutant compete for antibody sites on walls
4) phenolphthalein added
5) [] of pollutant inversely proportional to intensity of the colour

Question 8

What are immunoassays used for?

Answer 8

• screen samples in field to determine env damage
• identify regions of highest [] of different pollutant categories
• if pollution on site is high enough for further analysis

Question 9

What is the purpose of measuring DO

Answer 9

• ability of water to support life

- stable DO required for photosynthesis and cellular respiration

Question 10

What are typical levels for DO?

Answer 10

6.0 to 14.0 mg/L O2 (g)

Question 11

Does DO increase or decrease when temp decreases?

Answer 11

Increases

Question 12

What is the oxygen demand determined by?

Answer 12

In lab methods such as:

• BOD
• COD(chemical oxygen demand)
• TOC

Question 13

What does “oxygen sag” refer to?

Answer 13

The creation on an anaerobic env by the discharge of a pollutant into a waterway

Question 14

What are the 5 stages of an oxygen sag curve?

Answer 14

1. clean zone
2. Decomposition zone
3. Septic zone
4. recovery zone
5. clean zone

Question 15

What does the clean zone of an oxygen sag curve refer to?

Answer 15

When oxygen and bacteria levels are normal, and pollutant has not been discharged

Question 16

What does the decomposition zone of an oxygen sag curve refer to?

Answer 16

When pollutant has been released. DO is beginning to decline as bacteria active in decomposing the organic pollutant

Question 17

What does the septic zone refer to in an oxygen sag curve?

Answer 17

Lowest DO observed. Bacteria population at maximum. Septic zone
Complete when all organic pollutants are consumed

Question 18

What does the recovery zone refer to on an oxygen sag curve?

Answer 18

DO begins to rise through aeration (turbulence/movement through water system. Bacteria population declines from absence of food

Question 19

What is residual chlorine?

Answer 19

Amount dosed as a carrier in water to ensure biological stability

Question 20

Would you expect higher or lower values for turbidity, conductivity and residual chlorine in calm water compared to fast waters

Answer 20

Turbidity and conductivity go down

Residual chlorine goes up because of lack of aeration