Joined: 3/16/2012
Posts: 12
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with the new Methods update Rule from May 2012, EPA established 12 QC guildlines for all methods, if they are not specific in the method.
One such method is 2540D, Total Suspended Solids. I was curious what labs used for thier QC standard for this test. I make a standard using cellulose to equal 100 mg/L - a lot cheaper than buying commercially prepared standards.
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Joined: 10/5/2009
Posts: 45
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We make up a 100 ppm solution of diatomaceous earth, purchased as a reagent from one of the big lab suppliers (VWR, Fisher,...).
Chuck Lytle,
City of Portland, OR
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Joined: 10/12/2009
Posts: 10
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Just to save you some grief, EPA did not mandate the 12 essential elements but relegated them to option 3 if a method lacks QC. Then to top it off, they limited the whole section to chemcial methods so physical methods such as TSS are not included.
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