http://carnicominstitute.org/wp/preliminary-rainwater-analysis-aluminum-concentration/Preliminary Rainwater Analysis :
Aluminum Concentration
Clifford E Carnicom
Nov 02 2015
SNIPPET::
The current work, under these preliminary conditions and examinations, leads to an assessment of a concentration level estimate of aluminum (+3, ionic state) within the rain sample at approximately 2.5 PPM. A conservative approach in all manners of examination has been adopted in the preparation of this estimate, and the condensing of the sample is accounted for.
The Environmental Protection Agency in 2012 lists the secondary regulations for aluminum in drinking water as being within the range of 0.05 to 0.2 mg/L. This corresponds to a range of 0.05 to 0.2 PPM for this same standard. It is an interesting observation within the same report that Secondary Drinking Water Regulations exist as non-enforceable federal guidelines. The wisdom of that classification process can be determined by the reader.
Continuing with the most conservative approach possible, one is led to the assessment that this particular rain sample from a rural location in northern Idaho exceeds the EPA drinking water standard and health advisory by roughly a factor of 12.
The following reference statement from the United States Geological Survey (Bulletin 1827-A, 1967) may be of interest in the evaluation of importance that is to take place:
Subject: Preliminary Rainwater Analysis : 
Tue Nov 10, 2015 10:13 am
