Western Environmental
Testing Laboratory
Sample Integrity: Sample Collection

Sample Collection is the first, and perhaps the most important step in the analytical process. Poor sampling inhibits the labs ability to produce representative data of a sampling source. Sampling is comprised of 5 main steps:
1. Create a Field Sampling Plan
2. Contact lab to order bottle kit and discuss any scheduling complications
3. Conduct sampling following instructions from Field Sampling Plan and the lab
4. Release Custody of Samples to the lab, or a third party shipper
5. Review Sample Receipt to ensure correct analyses are ordered

What do each of these steps mean? Let’s take a closer look.

1. Field Sampling Plan- This is necessary to succeed in sampling, and generally should include the following:

  • General Facility Info or Sampling Locations
  • Contact Person and Samplers Name
  • Sampling Objectives
  • Facility of Location Information (PWS codes for drinking water)
  • Data Quality objectives
  • Sampling Points
  • Sample Collection Procedure
  • Sample Handling Procedure
  • Equipment Checklist
  • Equipment Preparation and Cleaning Procedures

 

2. Ordering Bottles and Scheduling Sampling- Call us to order your sample containers. The bottles provided will be bagged together into “sets” to keep each site organized. A cooler will also be provided. The lab will generally need the following information:

  • What are you sampling for?
  • How many sites do you intend to sample?
  • When are samples being collected and when will they be delivered to the lab?
  • Are any additional sampling supplies required (COCs, gloves, extra coolers, ice packs, custody seals, Ziploc bags, etc.)?

Depending on the situation, more coordinating and information may be required! For example:

Courier Pick Up or Drop Off– If you need sample containers dropped off at your site or picked up from a courier, it is wise to plan sampling around your labs standard courier routes. You can find WETLAB’s standard courier schedule here.

Sample Shipping– If samples are being shipped to or from a remote location, consider the amount of time samples will be in transit. If you are sending short-hold samples, selecting a “next day delivery” option may be necessary.

Subcontracted Work– Most subcontracting is shipped to southern CA and NV, therefore, factor this extra time in transit when making your sample plan. Furthermore, avoid delivering samples requiring subcontracting on Fridays, as they cannot ship out until the following Monday.

Weekend Work– Weekend work is not ideal, however, it is sometimes unavoidable! It is important, however, to notify your lab as soon as possible about weekend work so that staff can be scheduled to accommodate the request.

 

3. Sampling- Once the game plan is set, it is time to execute your sampling project.

  • Follow the steps outlined in your Sampling Plan and make sure to follow any special instructions provided by your lab.
  • Take note of the weather conditions, high and low temperatures can drastically affect how you pack and transport your samples.
  • Wear PPE! Gloves, glasses, masks, hairnets… they all serve a purpose to keep you safe and/or your samples clean.
  • Make sure to add the proper preservatives to your samples in the field, add custody seals to bottles or coolers if your sample plan requires them, and make sure to use bubble packaging for glass containers.

 

4. Releasing Custody of Samples- An additional responsibility of a sampler is properly documenting sample information and signing for any change of sample custody. The analytical Chain of Custody (or COC) is a required legal document submitted with samples to the laboratory. This document is a requirement for any sample submission to a lab, and serves numerous purposes:

  • Client and Reporting information
  • Turnaround time, compliance needs for reporting, report format, and QC requirements
  • Sample ID, Date/Time, Preservatives, Matrix, Number of Containers, and required tests
  • Miscellaneous comments, including hazard warnings, reporting requests, sample return requests, preservative notes, etc.
  • Relinquishing custody of the samples

 

5. Review Sample Receipt- WETLAB can send you an electronic “ sample receipt” which will list the entered information from your Chain of Custody, the receiving conditions of your samples (including anomalies), and an itemized list of all the analytical testing slated for your samples.
This is the final check before the testing will commence, so it’s important to review as soon as possible and contact the lab with any questions or concerns.

Contact WETLAB at (775)355-0202 to discuss your sampling requirements and project needs.

What is a preservative, and why is it important? According to the EPA, methods of preservation are relatively limited and are intended generally to (1) retard biological action, (2) retard hydrolysis of chemical compounds and complexes, (3) reduce volatility of constituents, and (4) reduce absorption effects.

In other words, the purpose of a preservative is to “freeze” the sample chemistry at the point of sampling so that what gets analyzed at the lab is as similar to the source as possible, despite the unavoidable delay between the sampling and analysis.

Some common preservatives include:

  • Sulfuric Acid (H2SO4)
    • Preservative for Nutrients: Total Nitrogen, Ammonia, Phosphorus, TKN, etc.
  • Nitric Acid (HNO3)
    • Preservative for Metals: Arsenic, Sodium, Lead, Copper, Iron, Mercury, etc.
  • Sodium Thiosulfate (Na2S2O3)
    • Preservative for Bacteria: Total Coliform, E. Coli, Fecal
  • Sodium Hydroxide (NaOH)
    • Preservative for Cyanide: Total CN, Free CN, WAD CN, etc.
  • Hydrochloric Acid (HCl) in VOA vials
    • Preservative for Volatile Organics: VOCs and Gasoline
  • Hydrochloric Acid (HCl) in Amber Glass
    • Preservative for Organics: Oil & Grease, Diesel, Oil, etc.

 

However, the most important, but often overlooked, preservative is ice. Keeping a sample cold (between 2-6C) is a requirement for nearly every analytical test we perform EXCEPT for metals analysis. It is generally preferable to use wet ice instead of ice packs when possible.

Sample containers, just like preservatives, are designed to inhibit the natural chemical changes which will occur in a sample as time passes. In addition to that, sample containers also serve a few other purposes:

  • To ensure proper volume is provided to a lab (all tests have a minimum required volume)
  • To ensure the lab has enough volume to perform the proper quality control
  • Some containers limit a samples exposure to UV rays
  • Some containers are designed to prevent sample contact with air
  • Some are sterilized and sealed to prevent bacteria contamination
  • Some containers are designed to limit sample absorption (plastic vs. glass)
  • Some are specifically designed to be loaded directly into an instrument (or even an autosampler for composite samples)

 

But how do I know which sample bottle and preservative to use? Simple, you ask the lab! By contacting WETLAB before you begin your sampling process, you will help ensure that you use the correct bottle and preservative. Our staff can also help you review your permit making sure the correct samples are taken at the correct time of the year (DPBs, LCR, SOCs), and making sure the correct methods are used for your sample matrix (drinking water, waste water, haz waste). We can even help with sampling requirements making sure your samples are collected as intended by your permit (LCR first draw, grab vs. composite), saving you valuable time that can be lost from unintended mistakes.

Be aware, preservatives and hold times are dictated by the analytical method and enforced by state/federal agencies and the laboratory. Cyanide species, Volatile Organics, Dissolved Oxygen, Bacteria, SOCs, DBPs, and many other tests absolutely require correct bottles and preservatives to analyze for compliance.

Contact WETLAB at (775)355-0202 to discuss your sampling needs. Our seasoned staff can help you determine which samples you need, how they need to be collected, and provide you with all the right bottles and preservatives to make sure your procedures remain in compliance.

We are pleased to announce Kathleen (Kat) Langford has joined the Client Services team as an additional Project Manager at WETLAB.  Kat has worked as a Wet Chemistry and Geochemistry Laboratory Technician with WETLAB and a Laboratory and Logistic Coordinator at Desert Research Institute.

As a project manager, Kat will be another point of contact at WETLAB to help coordinate projects, provide quotes, send reports, prepare invoices, provide job status information, and assist with general questions.

Kat studied nutrition/ dietetics and public health at the University of Nevada, Reno.  She also has volunteered with the Veterans Guest House, assisting with special events and fundraising.

Please help us welcome her to the team.  She can be reached via email at katl@wetlaboratory.com.

In our blog posts Lessons From the Lab we answer frequently asked questions from clients.  Find all installments of Lessons From the Lab here

It is important to know the differences for the client and the lab when the topic of compliance vs. non-compliance comes up. The simplest way to view it from a client perspective is that compliance data would be data that any type of regulator would review. It could be a state regulator or sometimes the EPA itself. Many times, compliance data will be sent directly to the state by WETLAB. In a more complex twist we have seen this past month NON-compliance data be subpoenaed to US District Court. This proves that even if the client indicates non-compliance we should be following all the normal rules as we do for compliance samples. All samples should certainly be collected properly as far as container and preservative types go and correct sample volume should be provided. From a lab perspective whether or not a sample is for compliance doesn’t really get discussed too often. It is simpler, and safer, to treat all samples the same. In rare occurrences, with lab and QA management oversight, protocols may be altered for non-compliance samples.

In our blog posts Lessons From the Lab we answer frequently asked questions from clients.  Find all installments of Lessons From the Lab here

What is a Reporting Limit?

A Reporting Limit (RL) is defined as the smallest concentration of a chemical that can be reported by a laboratory. If a laboratory is unable to detect a chemical in a sample, it does not necessarily mean that the chemical is absent from the sample altogether. It could be that the chemical concentration in the sample is below the sensitivity of the testing instrument. Concentrations below the RL are reported as not detectable at the RL or “less than” the RL. The RL value is often defined be each specific laboratory, so it is not uncommon to come across different RL’s when testing the same compound. RL’s act as safety protocols that allow laboratories to efficiently communicate the different variables correlated with testing and analyzing samples from a wide variety of sources and factors. It is important to identify the limit of concern that the client has when testing their sample to ensure that the RL is less than the regulatory limit. That enables a laboratory to identify whether a concentration of the chemical in question is above the regulatory limit of concern.

Our ongoing series Life of a Sample explores what happens behind the scenes at WETLAB.  If you missed parts one through four, check them out here!

At this point in our sample’s life cycle, the sample has been received, prepped, distilled/ digested, and analyzed.  The next step is entering all the collected data so that it can be transmitted to clients.  During this step, all the raw data is double-checked for inaccuracies and to ensure that all quality control samples have been included.  All data that can’t be migrated digitally is hand-entered by lab technicians, which is then checked for input errors such as incorrect dates or mis-typed numbers.  Catching these small errors is critical for ensuring data is reported correctly and on time for our clients.  This step is typically completed by the end of the day the sample finishes analysis.  After data entry, our sample will reach its terminal stage- reporting.

One of our talented lab technicians working to ensure quality data.

One of our talented lab technicians working to ensure quality data.

Our ongoing series Life of a Sample explores what happens behind the scenes at WETLAB.  If you missed part one, check it out here!

The next step for a sample at WETLAB is sample preparation.  This process takes one day, and involves several different processes and people.  During the first step, all samples undergo the same log-in and review procedure, and sample prep is where the tests begin to diverge dependent on which analyses are required.  Some samples, including many soil tests, require the compositing of several different samples into one representative batch.  For many tests, different filtered and unfiltered aliquots are needed; these pieces are split up into different bottles and preserved as needed.  Once properly split, the samples are released to the lab.

Before the samples reach the lab, laboratory scientists clean and prep the necessary equipment, and lab technicians prepare batches of samples based on the tests logged in during step one.  Some tests are ready to preform immediately, and those move on to step three.  For others, extractions are needed.  This includes TCLP (toxic characteristic leaching procedure), cyanide extraction, MWMP (meteoric water mobility procedure), and humidity cells.   Some of these extractions take more than one day, like humidity cells, which can continue for a few months up to several years.  Ensuring proper preparations are preformed allows the rest of the analysis to run smoothly.  After the filtering and extractions are completed, it’s time for step three: distillation and digestion.

A portion of the humidity cells currently being processed in the geochemistry lab.

A portion of the humidity cells currently being processed in the geochemistry lab.

 

MWMP extractions.

MWMP extractions.

At WETLAB, we are often approached by members of the community who are interested in having one of talented scientists come talk to students about chemistry.  We try to oblige as much as we can, and this year, we were able to do two completely different presentations for different classes.

One of the thank you letters sent in by the students.

One of the thank you letters sent in by the students.

First up was Andy Smith, our esteemed Quality Assurance Manager, who performed four “chemistry magic” experiments for 2-5 year old students at the Goddard School.  The first experiment was a re-appearing ink sign.  The ink was phenolphthalein indicator on paper, and once the paper was sprayed with Windex (making it basic) the message “Chemistry Magic” appeared.  Next, he created a blueberry Kool-Aid drink that, due to an oxidation- reduction reaction, would turn from blue to colorless.  With a quick shake of the bottle, it would return to blue for a few minutes before the reaction completed again. Third, he changed the color of a Bunsen burner flame to blue (with copper sulfate), orange (with sodium chloride), green (barium chloride), and  brilliant red (with lithium sulfate).  Last, Andy crushed aluminum cans by boiling a small amount of water in them to create steam.  Once the steaming can is turned over in ice water, the instant cooling causes the cans to crush themselves!

IMG_6662

Andy Smith helps to inspire some future scientists.

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Andy shows Chemistry Magic!

The next was Ellen Messinger-Patton, Kat Langford, and Andrew Tobey, who showed a presentation on water purity to sixth graders.  In order to show that tap water is just as safe to drink as bottled water, the kids compared and contrasted three samples, including bottled water, tap water, and an untreated sample from the Truckee River.  They used odor, color, pH, metals concentration, and turbidity to determine which water sample was the cleanest.  At the end of the hour, bottled water and tap water were a tie, and many of the kids agreed to try to drink tap water now.  The WETLAB presenters also spent a small amount of time relaying the importance of conservation, and what our hydrologic system looks like in the Truckee Meadows.

Ellen and Kat

Ellen Messinger-Patton and Kat Langford begin water purity demonstration.

At WETLAB, we think that science education is incredibly important.  We are happy to foster the next generation of scientists, and show them that science is not only useful, but also really fun.

We here at WETLAB are proud of our continued involvement in the community.  That involvement takes many different forms, recently including helping to inspire young minds to be interested in science.  Below, four WETLABbers share their experience presenting at a local high school’s career day. 

Career Day at Galena High School:  April 23, 2015

-Jennifer Delaney, AJ Lewis, Maiya Greenwood and Cory Baker-

Each year, Galena High School hosts a Career Fair for its sophomore students.  The career fair exposes students to the possibilities and realities of a successful career path.  Sophomores are invited because 10th grade is often the point at which they begin looking into colleges and potential career interests. Professionals from various backgrounds participate as speakers, teaching kids about their careers, their educations, how they got to where they are, volunteer services, the importance of networking and more.

WETLAB is now a veteran of this event, as this was our second year participating.  We met early at Galena High School to set up the displays at our booth. We had pamphlets with pictures of the lab, Erlenmeyer flasks with concentrated and dilute green slime, yellow and red acid vials to represent Nitric and Sulfuric Acid, a specimen cup with pink solution to simulate the presence of CN (properly labeled on the cup), and a tiny volumetric flask dyed blue to simulate the presence of MBAS.  Most importantly, we had the WETLAB mascot, the Labrador, wearing its personal protective gear to demonstrate proper PPE and to show that science can be fun.  These visuals helped to engage the students by prompting questions that led to discussions about their own interests and the breadth of scientific study and career paths.

We presented to six groups of students for 20 minutes each.  First we introduced what WETLAB does and the importance of our business.  Most students seemed knowledgeable about the importance of water quality and the need for environmental testing in Nevada, as well as locally here in the Truckee Basin.  Next, we each described our educational backgrounds, work experiences, and the importance of networking and volunteering.  With different backgrounds and career paths, students were able to hear our individual perspectives and learn about our unique experiences that led us to our current careers.  This helped to emphasize that there is more than one way to find an interesting and fulfilling career if you follow your passion.  While we all had varying messages, the resonating theme was to work hard, build a professional network, ask for help along the way, and keep your doors open to different opportunities.

It will be a few years before these kids enter the workforce, but their desire for a career in science and their level of interest is encouraging. Our industry has a promising future if we continue to feed and encourage young minds, teach them how to overcome challenges, and pursue what is important to them. Hopefully, networking in a more intimate setting plants the seed that will inspire our future workforce to grow and work towards their goals, prepare for higher education, and gain crucial career experience.

 

WETLab's booth to demonstrate a Laboratory Scientist career path.

WETLab’s booth to demonstrate a Laboratory Scientist career path.

 

Each year, Galena High School hosts a Career Fair for its sophomore students. The goal of the career fair is to expose students to the possibilities and realities of a successful career path. Sophomores are invited because 10th grade is often the point at which they begin looking into colleges and potential career interests. Professionals from various backgrounds participate as speakers, teaching kids about their jobs including education, how they got to where they are, volunteer service, the importance of networking and more.

Starting the day early at Galena High School, our group set up displays. We had pamphlets with pictures of the lab, a beaker filled with concentrated beet juice and an Erlenmeyer flask with diluted beet juice to show a small portion of lab processes. Most importantly, we had the WETLAB mascot, a Labrador, with its personal protective gear on to demonstrate the importance of safety and to show that science can be fun. These items provided visuals for the kids and were used during our presentations. We engaged the students by asking questions about their own interests and discussing how there are many different and exciting careers in the scientific field.

The first groups of students did not have many questions, but had a genuine interest in a diverse range of careers in the scientific community. The later groups were more vocal and asked questions ranging from work hours, how often we dealt with the public and the amount of technology available to work with. We hope we sparked some interest and motivation in the children that are our future.

We presented to six groups of sophomore students for 20 minutes each. We talked about what WETLAB does and why our business is so important. Most students seemed fairly knowledgeable about water quality and the need for testing in Nevada, as well as locally here in the Truckee Basin. Each of us discussed our education and work history as well as provided suggestions for volunteering and networking. With different backgrounds and career paths, the students got to hear our individual perspectives and learn about the unique experiences that led us to our current careers. This helped to emphasize that there is more than one way to find an interesting and fulfilling career if you follow your passion. While we all had varying messages, the resonating theme was to stick with your studies, despite the challenges, because in the end, a career in science is very rewarding.

While it will be a few years before these kids enter the workforce, their desire for a career in science and the level of interest is encouraging. Our industry has a promising future if we continue to feed young minds and encourage them, teaching them how to deal with challenges and overcome obstacles to pursue what is important to them. Hopefully, networking in a more intimate setting plants the seed that will inspire them to grow toward their goals, prepare for higher education and gain crucial career experience.