You are charged with analyzing 25 water samples for lead. EPA specifies action i

Question

You are charged with analyzing 25 water samples for lead. EPA specifies action if more than 10% of the samples test at greater than 0.015 mg/L. Additionally, EPA mandates a QA protocol of one Sample Duplicate for every ten samples and one Laboratory Fortified Sample Matrix for every twenty samples. The instrumental protocol calls for a calibration curve of at least four non-zero standards plus a Calibration blank. The calibration curve must be verified before analyzing any samples, after every 10 analyses, and again at the end ofthe anlysis. Prepare a table that lists the sequence in which the samples, spikes, duplicates and standards should be run in order to be compliant with the EPA regulations.

Explanation / Answer

Run samples to make a Calibration Curve, this includes

(ONE blank sample ( no Pb ) and FOUR non zero samples depending upon the range. (here 0.015 mg/L is given so Calibration samples should start from below that value and should be upto slightly more than 0.015 mg/L )

Next step should be to analyze 10 of the total 25 samples.

The next step is to Calibrate again. So we have to run the Calibrating samples.

( ONE blank and FOUR non blanks [ same we had used earlier to calibrate our system ] )

Now run any one of the samples again (Duplicate reading )

( from any one of the previously tested 10 samples )

Now test the other 9 of the remaining samples.   

The next step is to Calibrate again. So we have to run the Calibrating samples.

( ONE blank and FOUR non blanks [ same we had used earlier to calibrate our system ] )

Now take the reading of the one of the remaining sample ( 5 left now )

Now run any one of the samples again (Duplicate reading )

( from any one of the previously tested 10 samples )

Test for the remaining 5 samples.

The next step is to Calibrate again. So we have to run the Calibrating samples.

( ONE blank and FOUR non blanks [ same we had used earlier to calibrate our system ] )

STEP 1

Run samples to make a Calibration Curve, this includes

(ONE blank sample ( no Pb ) and FOUR non zero samples depending upon the range. (here 0.015 mg/L is given so Calibration samples should start from below that value and should be upto slightly more than 0.015 mg/L )

STEP 2

Next step should be to analyze 10 of the total 25 samples.

STEP 3

The next step is to Calibrate again. So we have to run the Calibrating samples.

( ONE blank and FOUR non blanks [ same we had used earlier to calibrate our system ] )

STEP 4

Now run any one of the samples again (Duplicate reading )

( from any one of the previously tested 10 samples )

STEP 5

Now test the other 9 of the remaining samples.   

STEP 6

The next step is to Calibrate again. So we have to run the Calibrating samples.

( ONE blank and FOUR non blanks [ same we had used earlier to calibrate our system ] )

STEP 7 Now take the reading of the Laboratory Fortified Sample Matrix. STEP 8

Now take the reading of the one of the remaining sample ( 5 left now )

STEP 9

Now run any one of the samples again (Duplicate reading )

( from any one of the previously tested 10 samples )

STEP 10 & 11

Test for the remaining 5 samples.

The next step is to Calibrate again. So we have to run the Calibrating samples.

( ONE blank and FOUR non blanks [ same we had used earlier to calibrate our system ] )

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.