50 questions

Question 1

What are the purpose of “16 Swedish Environmental objectives” and which of them are relevant for Recipient Control?

Answer 1

Environmental problems need to be handle right now and not passed on to future generations.

3. Natural acidification only
4. Non-toxic environment
5. Zero eutrophication
6. Flourishing lakes and streams
7. Good-quality groundwater
8. Balanced marine environment + Costal areas and archipelagos
9. Thriving wetlands

Question 2

How can you with an easy and cheap method show if a water body is stratified?

Answer 2

The temperature of the water can be measured. In a stratified lake there will be a big difference in temperature when it goes from epilimnion to hypolimnion.

Question 3

What is the compensation depth and how do you measure it?

Answer 3

Compensation depth is the rate of photosynthesis and respiration and this is equal to the visibility depth times 2. The visibility depth can be measured by using a disc and measuring the depth where it can’t be seen anymore.

Question 4

How does Oxygen-free bottoms occur?

Answer 4

If there is a lot of algae (due to nutrients) the visibility depth gets smaller which in turn lessens the photosynthesis that is happening in the water and less oxygen will be produced. Then dead material is being processed at the bottom oxygen is also needed and this also contributes to the oxygen-free bottoms. Stratification of the water has a big impact on this so that the oxygen doesn’t get to the bottom.

Question 5

Which parameters affect the speciation of iron (Fe) in the water column?

Answer 5

pH-level, redox and TOC

Question 6

How does the speciation of iron (Fe) affect nutrient (P,N) in the water column and in the sediments?

Answer 6

Looking at the pH – pe diagram we see that iron is a redox element that has different speciations depending on the pH or surrounding oxygen. If it is in Fe2+ no nutrients or trace elements can be adsorbed. If it instead is in the form of an iron hydroxide it mobilizes those kind of elements. Oxygen in the water column can release trace elements/nutrients. If we have eutrophication there will be less oxygen which leads to redox reactions. Reduction of iron hydroxides in the sediments happens because of degradation of organic matter then there is no oxygen left. The trace elements/nutrients bound to the Fe2O3 will then be released.

Question 7

How does the speciation of iron (Fe) affect metals (e.g. Cu) in the water column and in the sediments?

Answer 7

Looking at the pH – pe diagram we see that iron is a redox element that has different speciations depending on the pH or surrounding oxygen. If it is in Fe2+ no nutrients or trace elements can be adsorbed. If it instead is in the form of an iron hydroxide it mobilizes those kind of elements. Oxygen in the water column can release trace elements/nutrients. If we have eutrophication there will be less oxygen which leads to redox reactions. Reduction of iron hydroxides in the sediments happens because of degradation of organic matter then there is no oxygen left. The trace elements/nutrients bound to the Fe2O3 will then be released.

Question 8

Which parameters would you measure to identify eutrophication of a lake and where would you measure them?

Answer 8

TOC (surface), pH, oxygen (bottom), visibility depth, temperature.

Question 9

When during the year would you try to identify eutrophication and why then?

Answer 9

During the summer since that is when stratification happens with the different temperatures in lakes. This is also the time when we have the most algae blooming which contributes to the eutrophication.

Question 10

10 Explain what the following quality control procedure are:

a. Control of equipment
b. Duplicate
c. Blank
d. Comparison of sampler

Answer 10

a. Just milliQ and a sample that has gone through the equipment.
b. Control the sampling method be taking two separate samples of the same thing.
c. Make sure the equipment is correct. Doing all of the sampling steps but with MilliQ to see if there is any pollutants has an impact on the sample. This is then sent to the lab to check for trace elements in the equipment to see if it will have an impact on the result.
d. To analyze sample taken by two different samplers to see if the results differ.

Question 11

11. You suspect that you and your colleague, in some way, do not sample in the same way and introduce an error.
    a. Describe how you could assess this error and show if it is real or not.
    b. How would you statistically evaluate this difference?

Answer 11

a. To asses this error you and your colleague should take a sample at the same place and at the same. While doing this you will compare and see what differ from each other. It’s also possible that you both have done everything correctly and that other factors has impacted the result.
b. No fucking clue.
You compare your results and look into what factors that may have had an impact. This can be time of the sampling, equipment, season etc.

Question 12

Describe one situation where

a. knowledge about extreme concentrations is necessary.
b. knowledge about average concentrations is necessary.

Answer 12

a. An example is if there’s a industrial company that has a certain limit of chemicals that they are allowed to release it’s then very important to know the highest value that they will release. The maximum value is evaluated for a reason and can have an impact on the surrounding environment if it’s over the set limit.
b. When you want to gain a general knowledge of a certain area it is good to take an average. This is also useful since a lot of measurements can show different values but when taking an average you get a better picture with all of the values combined.

Question 13

What is the difference between single and composite samples?

a. How are they generated?
b. What are the pro and the cons for each of the ways?

Answer 13

a. Single: A single sample is taken and the concentration that is in the current sample is analyzed.
Composite: Several samples are taken an added into one and then divided. This to get a mean content, no spatial or time variation is visible.
b. Single:
Pros: Shows spatial or time variation (if many samples are taken)
Cons: Requires many samples to get a good view of the natural variation. Risk of extreme values
Composite:’
Pros: More reliable estimation of the mean, etc. Cost efficient.
Cons: Can not be used for volatile hydrocarbons. Increased risk of cross-contamination. Trends or patterns are not visible

Question 14

Explain the concept of sampling dimension.

a. Which “dimension is the best?
b. Why is it a privileged situation? Use the principle of sampling theory to explain.

Answer 14

a. Pile with particle. All samples should have the same opportunity to be sampled. Zero dimension, as good chance to choose any of the things that gets sampled.
b. Things can be in the way so that you have to choose another dimension.

Question 15

Explain the advantages and drawbacks of using:

a. Random or stratified (partially) stratified sampling:
b. Systematic sampling:
c. Systematic random sampling:

Answer 15

a. Random sampling is good to get the whole spectra into the study and to get an average. This might be a problem if there’s only a few samples taken since there’s a greater possibility that you get extreme values.
b. Good to get statistics and to get an overview. The disadvantage is that is an error is made it’s possible that it won’t be located since the result might be the same every time and you’re satisfied that you get a good result. With
time as an aspect it’s also possible that you miss important information if it regards a process with cycles.
c. Combining the two gives high accuracy since both the precision and bias is high. You are most likely to find a good trend as well as the extremes.

Question 16

Sample size.

a. How much material is “really” analyzed when addressing VOC?
b. How much material is “really” analyzed when addressing metals?
c. When is it not recommendable to prepare composite samples?

Answer 16

a. About 5 grams are taken for analysis
b. <1 gram is analyzed.
c. When handling volatile substances it’s not recommended since the can evaporate while taking the samples.

Question 17

Describe the splitting methods/instruments called:

a. Coning and quartering
b. Fractional splitting
c. Riffle splitter

Answer 17

a. You make a pile that looks like a cone. This is then flattened out and divided into quarters continuously until the required amount is reached. Important to avoid segregation since it’s easy for the different particles to redistribute when placed in a pile.
b. A bigger pile is split into smaller piles. This is a fast way of dividing the samples that is bigger and gives a more or less good result.
c. This equipment is used to make a sample smaller by dividing it in two several times.

Question 18

Sampling error

a. Describe and give an example of a systematic error resp. a random error.
b. What is the fundamental error? How can you address it?
c. What is the segregation error? How can you address it?

Answer 18

a. A systematic error can be a conveyor belt where material is lost on the sides. Random errors can be extreme values that occur when taking the sampling, normal destribution.
b. This regards the sample size and if by taking a too small sample you might miss important part of the target. By taking a bigger sample you can avoid it.
c. Segregation means that the target isn’t homogeneous and the material is divided, often having different density (like oil and water). This can be avoided by using sieving, flotation, agglomeration (surface forces), slope density segregation, slope friction ratio segregation, airflow and turbulence segregation and electrostatic segregation.

Question 19

Suggest a sampling procedure for a pile of waste (slag from an industry with a particle size up to 30 mm). The pile is 50 meter long, 10 meter broad at the base and 3 meter high). What are the critical factors to be addressed when sampling in such situation?

Answer 19

String dividing is good since you get the cut-through of the whole profile.

Question 20

21 At which depths would you sample a lake that is 20 m deep and why?

Answer 20

Measurements taken at this depth the thermocline should be located by measuring the temperature. Then sample at 0,5 m below the thermocline surface and 1 m above the bottom.

Question 21

At which depths would you sample a lake that is 20 m deep and why?

Answer 21

Measurements taken at this depth the thermocline should be located by measuring the temperature. Then sample at 0,5 m below the thermocline surface and 1 m above the bottom.

Question 22

What do you separate if you filter the water with 0.2 um filters?

Answer 22

Separate what is in dissolved or particular. Colloids can be separated or get through here as well as being in the sample.

Question 23

What could happen with the fractions if you don’t have the possibility to filter your sample on site and instead ask the laboratory to filter the water?

Answer 23

Speciation can change. Fe2+ in the water. Pumping up, add oxygen switch to Fe2O3 forming in the water column. Leave it will lead to colouring. Adsorb the metals. Lab filtrate away the particles. Dissolve the whole sample, small sand will give extreme values.

Question 24

How should you store water samples and sediment samples until they reach the laboratory for analysis and why?

Answer 24

They should be stored cold and in darkness so that heat and warmth don’t start any reactions. Metals not in glass and organic -> plastic. Avoid oxygen.

Question 25

Name a situation/”identification of an environmental problem” when it is good to use a Ruttner sampler?

Answer 25

This is useful to measure at a certain depth and can be useful when comparing differences between the metalimion and epilimion in different seasons. Eutrophication.

Question 26

What is the difference between looking at the results from water samples and water moss samples?

Answer 26

In water samples you can find both saturated and particles while plants such as water mosses only absorb saturated substances and longer period of time.

Question 27

If you want to trace climate changes by analyzing the sediments – Which sediment sampler would you use?

Answer 27

I would us a corer to get a profile of the sediments (lamination).

Question 28

Explain how the lead (Pb) concentration in sediments can be used to trace periods of Economic Development several 100 years ago.

Answer 28

After WWII an industrial revolution took place which led to an extensive metal production which in turn released a lot of lead pollution. Economic changes, wars and sicknesses.

Question 29

A new harbor should be established and sediments needs to be dredged in order for the ships/boats to reach the harbor. Your task is to determine if there are any pollutants that could be spread during the dredging. Which sampling equipment would you use and why?

Answer 29

A corer at different places to see if there’s any risk of materials oxidizing and release toxic substances.

Question 30

What is the difference between a direct and an indirect flow/discharge measurement method?

Answer 30

The difference is that the direct methods involves taking measurements of the media while the indirect ones are based on theory, history and predictions.

Question 31

Explain how a measurement using a rod suspended current meter is to be done.

Answer 31

A area is divided into subareas (at least 30) then two different depths are measured since the water differs a lot depending on the depth. Then the mean of this value is taken and a summary is made, this times the area.

Question 32

How does the water flow affect the metal concentration in a river?

Answer 32

Spring flod. Release of metals (constant). Dilution. Lower concentration shows up. Weathering in winter. Iron sulphides started to weater due to O Fe3+. Snow cover. Wash out the dissolved metals from the winter.

Question 33

Explain how soil collection from a screw should be done.

Answer 33

Preferebly in combination with groundwater installations. When the screw is picked up the upper layer should be removed since it’s often soil that has fallen when the screw was pulled up. The outer layers are then taken directly from the screw. This can be done by hand if rubber gloves are used. The soil is then put into safe containers and in a cold space.

Question 34

What is sulfide soil? Why should you be concerned about it?

Answer 34

Sulfide soil is soil that contains iron sulfide minerals. When these soils are exposed to oxygen they react and form sulfuric acid. This in turn can release iron, aluminium and other toxic substances within the soil.

Question 35

When is it recommended to sample from pits? What are the main advantages and disadvantages?

Answer 35

Then the soil differs, in till with rocks or heterogeneous composition. This gives a good overview. It is limited to 3-4 meters into the ground and difficult to safely use deeper than 2 meters. It’s not suitable for below the groundwater table and may change the ground’s stability.

Question 36

When is it recommended to sample with a screw? What are the main advantages and disadvantages?

Answer 36

It’s low impact, few safety risks, possible to install groundwater pipes at the same time and can be combined with geotechnical investigations. The disadvantages are that samples can be disturbed, it doesn’t provide an overview and is difficult in areas with coarse material.

Question 37

Sample handling

a. What are the common on site analysis that can be done when sampling soil?
b. When sampling soil from a profile, when is it allowed to mix soil and when it is not?
c. Describe how the xrf works
d. Describe three different sample preparations that can be used for XRF analysis. what are there pros and cons? How can you compensate for the cons?

Answer 37

a. XRF and PID (volatile substances)
b. Don’t mix: type/texture, consistency, colours, odor, c. above/below groundwater.
XRF (X-ray fluorescence) is a non-destructive analytical technique used to determine the elemental composition of materials. XRF analyzers determine the chemistry of a sample by measuring the fluorescent (or secondary) X-ray emitted from a sample when it is excited by a primary X-ray source.
d. Wet sample, heterogenous – different value. Several times at the same place and then this at different places.

Question 38

How can you plan your sampling procedure to reduce the cost for sampling and analyzing? Explain shortly about

a. How to choose representative sampling sites?
b. Field measurements (pH, XRF, PID)
c. How to reduce analysis cost in the laboratory?

Answer 38

a. Talk to people who has previously sampled on the location and visit the site. Look at background information. Oil spill – talk to someone who has worked at site a long time.
b. To measure the pH a pH meter is used. The XRF needs to be calibrated against a valid background depending on what the purpose of the survey is. It’s good to remember that the XRF sends out a x-ray which can be harmful.
c. Make the necessary measurements on site to determine which samples are the most interesting and valid to send to the lab. Send a small sample if silt or clay since they represent the extremes most often. Send a few and store the others.

Question 39

What is generally the difference in water quality between surface water and groundwater?

Answer 39

The groundwater in under the surface and fills pores and sediments. It is cleaner than surface water since it gets filtrated in pores and sediments while the surface water is exposed to shifts in temperatures, oxygen and organic matter.

Question 40

How does the porosity of a soil/rock effect the velocity of the groundwater?

Answer 40

Large porosity (larger particles) water flows faster through. Escars ice age, a lot of sand. High flow of ground water (samples should be taken here). Contamination travels fast as well.

Question 41

In which direction is the main groundwater transport? Horizontal or vertical?

Answer 41

Horizontal.

Question 42

Mention three methods to install groundwater pipes

Answer 42

Drilling, Hollow stem auge (spiral), Direct push kommentera

Question 43

What is important to consider when installing the groundwater pipe filter?

Answer 43

The hole can collapse and it can be difficult to bring the filter sand to the correct depth. Alla faktorer

Question 44

Which material is recommended when monitoring metals such as copper and zinc?

Answer 44

HDPE or PTFE

Question 45

List three technics (pumps or other devices) to sample groundwater. What are the main advantages and disadvantages?

Answer 45

Peristaltic pump: doesn’t expose the water to oxygen which doesn’t change the speciation of elements. Switch tube. Usable up to 7 m and not suitable for volatile substances.
Pressure pump: Installed under the groundwater table which makes it possible to measure volatile substances. Good capacity (deep). Problems with poor drainage or when water has a high turbidity. Risk of cross contamination.
Bailer: Simple and inexpensive so cross contamination can be avoided. Available with a valve so that sampling can be done at different levels. Bad for circulation of ground water. Risk of losing volatile compounds. Contact with oxygen.

Question 46

Explain the common procedure for groundwater sampling

Answer 46

Measure the groundwater level.
In some cases also the contamination layer at the water table. (sound/light meters, colour past on meters, transparent bailer)
Circulation pumping – choosing the correct equipment for the correct volumes. Pump 3-5 times the required water volume. The volume of the tube can be estimated using the rod diameter and the depth below the water level. Note how good the inflow to the well is – can be useful in later risk assessment. Pump with small capacity to avoid mobilization of fine material. Avoid emptying of the groundwater pipe.
Use plastic gloves. Label bottles. Clean equipment, wash tubes, etc. Must be done before the pumping. For using the bailer or tube-pump, lower it to the desired water level, avoid lowering too far to prevent stirring up fine materials from the end of the groundwater pipe. Use pumps only with low flow. Filter the sample in situ. Fill bottles carefully. Fill out until the water overflows. Turn on the cap. Keep the bottles cold.

Question 47

What are the common on site analysis that can be done when sampling groundwater?

Answer 47

Conductivity, pH, temperature and redox potential.

Question 48

Why should you always filter groundwater? Contradictory to surface water that can vary

Answer 48

Filter prevents fine particles from entering the tube and affecting the sampling, sand particles. No contact with oxygen, important to know which is in particular form and dissolved.

Question 49

The lost of compounds during the transport
The analytical error
The contamination induced by the preparation of the sampling bottles
The error induced by the sampling technique used by different samplers
The overall sampling and analytical error
Which other sources of error could you assess using this quality control design?
Traditional and express transport
Sample pretreatment

Answer 49

a3 & a4
a6 & a7
a1 & a2
a8 &a9
...
a8 & a10
a2 & a3