Question

1.     What contaminants may remain behind after physical & chemical methods used to purify water, and how can these be removed?

2. Describe two variables that may not be controlled for that limit the accuracy of assessing the effectiveness of physical and chemical treatment methods:

3. Why would 0.01 ml (10µl) of untreated pond water be used when creating an agar plate sample, but 10 ml of treated water be used when creating an agar plate sample?

4. Why would sample testing be done in triplicate?

Question number three is comparing the samples taken just from the pond water without treatment and the samples that were filtered or chemicaly treated. The small amount of sample is the one just taken from the pond and the larger amount of liquid is from the samples that were treated. I am curious why the samples just taken from the pond were so small compared to the treated samples. Also the smaller samples straight from the pond were multiplied by a dilution factor before being compared to the larger treated samples. This lab had to do with counting bacteria growths on an agar plate before and after filtration.

Answer 1

Thanks for asking the question.

To answer the first question

The contaminated aquifers have been used and may well be used more extensively in the future to augment the supplies of uncontaminated water. Wellhead treatment may also be an optimal remedy for low concentrations of contaminants in potential water supplies. But current wellhead treatment technologies are materials intensive and are not energy efficient. Improvement in the efficient water treatment technologies should be developed both for the more cost-effectively destroying recalcitrant organic compounds as well as for the removal of the toxic metals. Emphasis should also be placed on the technologies that treat a broad spectrum of chemicals.

I also feel vapor mitigation could be built into all new construction sites on or near known groundwater plumes; this could be imposed proactively as part of the local or state building codes or other requirements or imposed as institutional controls at regulated sites. Even the reverse Osmosis Systems will remove common chemical contaminants (metal ions, aqueous salts), including sodium, chloride, copper, chromium, and lead; this may reduce arsenic, fluoride, radium, sulfate, Ca, Mg, K, nitrate, and P etc

Can you please elaborate on question 2 and 3. I felt I could answer more efficiently If I can clearly understand what are the key doubts

Moving on to question number 4

Using the triplicate method will reduce the need for repeating experiments, and allow you and others to have more confidence in your results. Robust unimpeachable results are key to a successful algae program.

Triplicate ponds will allow clear identification of water resources operating outside the expected range, triplicate methods are an important evaluative tool for identifying measurements that fall outside the expected range.     

Please do let me know if I can help you with anything.

BEST OF LUCK

Thank you