Question

8. What kind of sampling strategy would you use in the following situations? Take into consideration the spatial and temporal variability you expect to encounter. What type of sampling would be preferred: grab sample, composite sample, or continuous monitoring?

a. To study the contamination of fish in a river where a chemical company has a waste water discharge outlet.

b. To identify accident release of chemicals by the industry mention above.

c. To implement strategies to reduce smog formation in your city.

d. To study the effect of auto exhaust on the air quality in your city.

e. To identify ground water contamination around an abandoned chemical factory.

f. To determine if apples from a sprayed orchard are contaminated with pesticides.

Answer 1

Grab sampling:a grab sampling is a discrete sample which is collected at a specific location ata certain point in time.If the environment is spatially then a single sample is not representative and more sample needed to be collected.

Composite ample:it is made by thoroughly mixing several grab samples the whole composite may be measured or random sample from the composite may be withdrawn and measured.

(a)for contamination of a fish in a river is made by composite sampling.by the above definition.

(b)accident release of chemicals can be made by grab samling because by grab sampling at a specific location it is taken

(C)to implement strategy and reduce smog formation in your city used continuous monitor the sampling values

(D)to study the effect of auto exhaust in your city can be seen by grab sampling at acertain point .

(e)to identify ground water contamination at certain pont we use grab sampling because at a certain point we calculate only grab sampling.

(f)for contamination with pesticides we use cmposite sampling