What needs to be clarified
Check whether the studies are comparable before attributing changed readings to a particular discharge or extending them to the whole water body.
Materials to prepare
- Complete laboratory and sampling records identifying every sample
- A plan of the water body, suspected outlet and comparison locations
- Information on rainfall, sampling time and source operating conditions
What to compare
- Compare locations, measured parameters and sampling conditions
- Separate an observed change from an assumption about its cause
- Identify missing background data and possible alternative inputs
Possible outcome of the analysis
A possible outcome is a table of comparison conditions and a list of further information needed for environmental interpretation.
Limits of the conclusions
A single sample describes a particular place and time but does not by itself identify the pollution source or responsible party.