Laserfiche WebLink
GT ENVIRONMENTAL LABORATORY (GTEL) <br /> S-',;,10ARD OPERATING PROCEDURE <br /> CONCERNING FIELD PRESERVATION OF BTX SAIMPI ES <br /> BY ACIDIFICATION <br /> SOP 12 <br /> if specially prepared acidified :^.als are not available, apply <br /> the following Field Procedures, us,.ng the field acidification <br /> kit. The kit contains: <br /> a) 500 cc glass Measuring cup or breaker. <br /> b) dropping bottle of 50% hydrocloric acid or nitric <br /> acid. <br /> c) narrow range pH paper, 1.0--2.5 pH range. <br /> d) glass stirring rod. <br /> 1. Collect anoroximateIy 300cc of water in beaker. Try to <br /> minimize turbulence, bubbling, and time of exposure to the <br /> air. <br /> 2. For inorganic analysis: use 50% nitric acid <br /> For volatile organic analysis: use 50% hydrocloric acid <br /> Add 30 drops of 50% acid to measuring cup. Hold dropper <br /> completely vertically. <br /> 3. Gently mix with glass bar. <br /> 4. Remove bar and touch wetted tip to the oil paper and check <br /> color code to assure it is below pH 2. As more acid is <br /> added the pH goes lower. Discard used ati strip. <br /> 5. Add more acid if necessary. Too much acid is not a problem, <br /> just record how much was added (this will be helpful next <br /> time) . Don't waste time trying to get it right - just add <br /> plenty of acid to get it below T)H 2. Ideally, once you know <br /> how much acid needs to be added at one well, that amount <br /> will be sufficient for the rest. Fc,,;,_ver, test the Did each <br /> time. <br /> 6. Pour the water into the vials crecar_.. for that well and r. <br /> Or, w.Lth no bubbles 4nsice. Again turbulence and hubblina <br /> are to be minimized. :also note that it is iIonortant thcz <br /> all of the vials for a given well be poured and sealer cne <br /> richt a=ter m other. Make sura the =boor cellected _s <br /> enough to f'_1? all of the v?a's with score to s_a_e az ::e <br /> end. The vclume co,.lacted can he ,ncreased bu: remember tc <br /> proportionally increase _he amount cf acid adder. <br /> dca4_o^ does n t _ o_w_b c 11 ^c. always chill Aci1 <br /> ill <br /> sa :les <br /> and Ship 'ria a:._ for next day delivervT <br />