The US NADP program uses a bucket that closes when rain is not present, and collects larger batches of rain weekly, so temporal variability during a rain storm is not as much of an issue. This study was looking at pH, but found wide variances during storms, between storms, and at diffferent locations in the same storm:
http://nrs.fs.fed.us/pubs/gtr/gtr_ne25/gtr_ne25_053.pdf

Even multiple samples purportedly taken contemporaneously show variances:
http://metabunk.org/threads/135-Chemical-Composition-of-rain-and-snow?p=1410&viewfull=1#post1410

The text you provided sound like they are tweaking to get “particular” results.

This instructions here for surface waters are a gross example of getting what you want:
http://www.geoengineeringwatch.org/html/watertesting.html
“Surface water tests have the highest numbers and will really freak you out when you get the results.
If you are testing a pond, then the only thing different is how you collect the sample. The very bottom of the pond is where the elements stack up. Turn your jar upside down and get the mouth to the bottom of the pond or still water….the older the pond the higher the readings. Turn the jar over and collect both the water and a LITTLE of the bottom sediment. You will need to put the lid on underwater before you lift the jar off the bottom and out of the water….thats it!”

This is how the “Shasta Bunch” got 4,610,000 ug/L in one of their samples, it was loaded with mud!

Marcel Marceau I’m in UK. Any advice on how to stop windblown particulate ie dust and pollen etc getting into my rain sample jar? Any help would be appreciated.
Yesterday at 14:37 · Like.

Chemtrails Project ‎Marcel Marceau, the best advice we have right now, as there is no perfect way to capture rain, is to make sure there are no overhead obstructions (trees, canopy, etc). If the rain sample is collected in a clearing, and you get the first 5-10 mins of rain, then that is as close to “pristine” as we will get. From there the determination of growth can still be patterned with the other samples.
Yesterday at 16:07 · Like.

Marcel Marceau Just spoken to some mates, and their advice is not to sample at the beginning of the rain. The reasoning behind this is, if there is any windblown particles in the air, the rain will pick them up and deposit them. Therefore the longer the rain is on before collection, the less dust and spores and pollen etc. will be collected in the sample.
Sounds sensible to me. What do you think?
20 hours ago · Like.

Chemtrails Project the first 5-10 mins of rain is what contains the “contaminates”. Later rain samples have provided low readings. The “dump” comes early
19 hours ago · Like.

Seems like their rain sampling ideas need a bit of tweaking to get impartial results.

http://fr.wikipedia.org/wiki/Tra%C3%AEn%C3%A9e_de_condensation

Les principes de formation des traînées de condensation sont donc similaires à ceux des nuages et sont expliqués en détail par la physique des nuages.

Please stop with your misinformation is completely crazy to think that the simple condensation reactor can hang out in the sky and expand and make artificial cumulus clouds .. this is ridiculous! It is a chemical reaction that such an effect occurs! So it’s not contrails but chemtrails!