Transcript Creating your sampling protocol

Creating Your
Sampling Protocol
Harold Flachsbart
Chemistry Lab Director
Northeast Laboratory Services
Sampling Program
Sampling Programs should be created to take into account many
factors:
• The reason for sampling
• State mandated
• Mortgage mandated
• Homeowner wants to know
• The best location for sampling
• The frequency of sampling
• Sampling technique needed to obtain representative samples
• Low Flow/Slow Purge
• Grab
• Composite
• Correct sample containers for required tests
• Storage conditions and hold times for required tests
Sampling
• Choose a laboratory to do your analysis
• Make sure the lab you choose hold Maine State Certifications for
the tests you require
• Find out sampling requirements
• Bottle Type
• Bottle Size
• Preservation
• Following specific guidance from the laboratory is important
to ensure the analysis are preformed correctly
• Sampling Procedures
• Sample Handling
• Avoid Contamination
• Clean Surfaces
• Use Common Sense
• Whenever a sample of water is taken for analysis, it should be
recognized that regardless of the sample size, it represents
only a small fraction of the water being sampled
Wet Chemistry Testing
• Why is the testing required?
• What method is used to preform the required test(s)?
• What bottles are needed to perform the test?
• Each analysis has an EPA or Standard Method approved
procedure and each lab performing that procedure must have
State of Maine certification to do so
• Metals analysis requires 150 mls of sample
• Total Coliform/ E-coli requires 100 ml unpreserved sample
• Nitrates/Chloride/Fluoride require 100 mls unpreserved sample
Lead and Copper Testing (14 day hold time)
• Why do we test for lead and copper?
• Health effects
• gastrointestinal distress (Cu)
• liver or kidney damage (Pb, Cu)
• high blood pressure(Pb, Cu)
• Delays in physical and mental development (Pb)
• Preventative action
• Who tests for it?
• All Community and Non-Transient Non-Community Water
Systems
• What are the action levels
• 1.3 ppm - Cu
• 15 ppb - Pb
• Sources of positive results
• Corrosion of pipes
• Erosion of natural deposits
• Corrective Action
• Completely flush pipes
• Replacing pipes
Sampling Lead and Copper
• Know your designated sample sites
• Kitchen, bathroom sinks, break room sinks, drinking fountains
• Communities sample single family homes or multi-family homes
• Flush your sample site water lines for until the water is cold.
• Why?
• What does that do?
• DO NOT RUN WATER FOR AT LEAST SIX HOURS
• Collect 1st draw sample using Lab’s (NEL) approved sample
containers
• It is not recommended to collect samples if hold time exceeds
10 hours
• Return sample containers within 14 days of sample collection
to laboratory
• Be courteous and do not wait until last day to return sample
bottles
• When returning large amounts of sample containers, give the lab
a few extra days
• Note sample collection times to make sure the water has met
the six hours of no use time. It is important to maintain
correct sample collection times and for the data to be entered
on the chain of custody form for the laboratory (NEL)
VOC Testing
• Make sure you know what State/EPA tests you are are
required to take
• If you do not know, call the State of Maine Drinking Water
Program (DWP) before you call the laboratory (NEL)
• The laboratory will assess the information given by DWP and send
you the containers needed for the sampling event
• Why is this test needed?
• What do you do if you receive a positive confirmation?
Chain of Custody
• Written documentation of the handling of your sample
• A traceability document used by DWP, DEP, Engineering Firms,
Businesses, and Private Property Owners
• Legal document showing:
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Where the samples came from
What tests are required
Who collected the samples
Who relinquished the samples
What type of samples are they (Grab, Composite)
What type of bottles are the samples in
What is the sample matrix (DW, GW, WW)
Do the samples have any known Hazards
Sample Handling
• All State of Maine certified labs should have SOP’s in place to
guide the proper handling of samples.
• Example - BOD
• Testing requires a specific volume (1000ml) of sample
• In a certain bottle (1 liter plastic unpreserved)
• Samples must be kept at 4° C until they reach the lab
• Samples need to reach the lab and be set up within 24-hours of
sampling
• Sample must incubate for a 5 days ± 2 hours
• Sample preservation refers to sample handling aimed at
preventing or minimizing chemical or biological activity
• Correct preservative (temperature, acids etc.,) are vital for proper
testing
• Samples are usually (whether preserved with acid or not) kept at
a consistent temperature of 2-6° C
• Samples are usually transported in coolers to maintain a
consistent temperature
• Sample seals are used to maintain the integrity of the sample
containers, the introduction of the samples to the container,
and the transportation of the samples to the lab
• Sample holding times are referring to the maximum amount
of time allotted to still achieve valid results
• Holding times for microbial organisms are usually 24-48 hours
(fecal coliform, salmonella, helminthes ova, enteric viruses).
• The Analysis of Total Coliform Bacteria samples for drinking water
compliance samples must be started within 30 hours of
collection.
• Metals analysis requires that the samples be acidified within 2
weeks and analyzed within 6 months.
• Once samples are received at the laboratory they are
categorized, labeled, and stored in a temperature controlled
cooler until they are tested
Analysis of Samples
• Water chemistry analysis is used to identify the amounts of
certain unknowns in water. Water has certain qualities and
properties.
• Instruments of analysis
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Ion Chromatography
Gas Chromatography
Spectrophotometry
Inductively coupled plasma mass spectrometry/optical emission
Electrode chemistry
Wet chemistry
• EPA and Standard Methods
Quality Control
• Measures the results from analytical work to determine accuracy
and precision
• Precision shows how reproducible the results are
• Accuracy shows how close to the actual results you are
Some of the controls that are used to obtain precision and accuracy are:
• Laboratory Blanks or Field Blanks- to identify contamination or background
interference. A trip blank is run as a sample.
• Split/Duplicate samples - used to compare labs or to determine the precision of an
instrument.
• Spike samples - have added a known amount of what is being analyzed to a
sample. These are used to test accuracy and matrix interference in an analysis.
• Calibration or reagent blank - used to zero the instrument. It can be used to check
drift as well.
• Calibration standards - known quantities of analytes used to create a curve. This is
programmed into analytical equipment to derive a quantitative concentration of
the analyte in question.
• Continual Calibration Verification (CCV) - used every 10 or 20 (depending on
method) samples to check the continued accuracy of the calibration curve.
• Laboratory Control Sample (LCS) - a blank spiked with known concentrations
representative of target analytes. This is derived from a source different then the
curve to test the accuracy of the analysis.
• Laboratory Control Sample Duplicate (LCSD)/ Sample Duplicate - used to show
precision of the analysis
Reporting Analytical Data
• All data must be traceable to its procedure
• All procedures must be EPA or Standard Method procedures,
following SOPs that are approved by Laboratory Certification
Program in the State of Maine
• All data generated by the analyst is put through a three person
review system before final validation
• All data is reviewed, verified, signed and dated by the analysts
and Lab Director before reporting.
• If errors are found during the review of analytical data they
must be corrected before the data is validated and reported
• Corrections are made by a single line through incorrect information
• The person making the correction may initial and date the correction
• An explanation is needed for the change in data
• The correct data is recorded
• The data is corrected in the Laboratory Information Management System
(LIMS) if needed
• Mathematical corrections such as significant figure errors are corrected
in the same way
Cooler filled with bottle orders according to location
YSI Meter that measures pH, Temperature, DO, and Conductivity
Variable speed pump used to pump water out of well
Setup for wells to be field sampled
Turbidimeter
Water Level- measures water levels in the well vs. what you pump out of it
Questions?
More information?
• Call Northeast Laboratory
• 1-800-244-8378
• Servicing All Your Analytical Needs for Forty-Two
Years!!