Subject: What is the average concentration of nitrate and phosphorus in sewage water

salutations, me and my partner are doing a science project in relations to 
the environment and pollution.  We are testing certain plants to evaluate 
whether or not they can remove pollutants from polluted waters/sewage 
waters and if so, then at what percentage of polltants can they remove in 
a broader sense. This is one of the small questions we must answer in 
order to properly evaluate our project to come to a valid conclusion. We 
hope that you can provide the appropriate the unit of ppm  in relations to 
an average concentration....thank you very much for your help and time, 
from two novice environmentalists  

Re: What is the average concentration of nitrate and phosphorus in sewage water