Water Sampling and Characterization Doing More With Less

Transcription

1 Water Sampling and Characterization Doing More With Less Environmental Doug Johnson April EnviroTech 2018 Right Solutions Right Partner 1 Right Solutions Right Partner

2 Presentation Summary This presentation will outline the history behind analytical testing for groundwater samples, the journey towards lower detection limits, progressive analytical improvements and the benefits of using sample miniaturization to overcome low flow well conditions and other challenges Disclaimer: there will be lots of small fonts, very few graphics and no tables in this presentation and no animals were harmed in the making of this documentary 2 Right Solutions Right Partner

3 Historic Background For over 40 years, maximum concentration limits were driven by Guidelines, Regulations, Approvals or Directives In general, analytical methods were based upon published EPA References or on established performance-based modifications to those same EPA methods so they were considered fit for purpose through following method validation procedures as outlined in the lab s Quality Manual Over time, Accreditation to ISO Standards was the driving condition for method improvements meaning you needed to have precision and accuracy information as well as statistically derived detection limits that met Reportable Detection Limit (RDL) objectives This meant you could modify the reference EPA Method as long as you documented and demonstrated equivalency to the Reference Method followed then by Accreditation and regular performance testing (PT samples) where available Early on, there was little consultation required between Regulators and the lab sector with regards to seeing lower concentration levels as the existing technologies already met the objectives 3 Right Solutions Right Partner

4 Changing Objectives Updates Required Eventually, new information about Environmental toxicity, stability or receptors meant that some of the original maximum allowable concentrations were now too high so they were lowered by the Regulatory bodies and impending changes were rolled out to the labs for review and method development Those lower objectives meant the labs would need to drop their Reportable Detection Limit (RDL) for the impacted parameters in some cases more than an order of magnitude For certain parameters, the RDL could be over 10x higher than the calculated Method Detection Limit (MDL) so labs had room to adjust the RDL lower without the need for re-validation or significant modifications to the existing method In other cases, the RDLs were higher than the new target levels so the labs needed to review and modify methods accordingly The expectation was that the labs could always see lower if they needed to and we had no choice but to do so to meet Regulatory demands 4 Right Solutions Right Partner

5 History Seeing Lower Levels Historically, lower detection limits meant extracting/digesting more sample to increase extract concentrations before analysis The three easiest solutions to lowering the MDL would be increasing the amount of sample extracted for the test (i.e. extracting 500mL of water to 1L), increasing the volume of sample digested (i.e. digesting a 10mL aliquot of sample to a 50mL aliquot) or by taking extracts to lower final volumes (i.e. 2mL final volume down to 0.5mL final volume) Where possible, these techniques were used in tandem to increase the overall extract concentration prior to analysis in attempt to overcome detection limit challenges With GC/MS analyses, labs went from performing the traditional Open Scan analysis to Selected Ion Monitoring to increase instrument sensitivity By using a pre-concentration strategy, the sensitivity limitations for the existing instrumentation available at the time could be overcome allowing the labs to reach lower MDLs 5 Right Solutions Right Partner

6 Where Did That Come From? Unfortunately, having to use more water or smaller final volumes prior to analysis meant a concentration of contaminants could also occur Labs had to institute better protocols and systems to limit or eliminate potential contamination sources that would result in false positives Trace backgrounds that were historically below the detection limit were suddenly concentrated and detectable levels of target analytes were now discovered from a variety of sources Labs found that trace amounts of compounds in solvents, extraction fluids, preservatives, glassware and sample containers could contribute detectable levels of contamination that were not previously seen at the higher Detection Limits This meant labs had to source out ultra clean chemicals for extractions and preservatives and glassware proofing was continually performed for problematic chemistries 6 Right Solutions Right Partner

7 Field Issues Consultants quickly became aware of the potential for low level contamination from sample containers and field practices so SOPs were developed to address those new challenges Sample containers could potentially be contaminated as received so the requirement to pre-rinse the sample bottles was implemented, and sample preservatives were provided separately Re-usable sampling equipment had to undergo rigorous cleaning, rinsing and proofing so sources for disposable sampling equipment were identified and implemented Contamination from the air could potentially result in false-positives so field blanks and procedures to reduce atmospheric exposure were implemented such as filtering dissolved parameters in a controlled area after sampling, or having the lab filter and preserve samples upon receipt A big issue was Low Flow wells with slow recharge rates that could not produce enough water in one sampling attempt so those wells were revisited as many times as necessary to get enough sample for the lab to reach the required detection limits for all of the target parameters 7 Right Solutions Right Partner

8 Better Instruments - Better Results Over time, instrument manufacturers developed better instruments with higher sensitivity and selectivity making improvements with each successive generation Sample introduction systems were developed and refined to use less sample while ensuring carry over and system backgrounds were minimized Orders of magnitude improvement in sensitivity could be realized with the newer technologies and detectors such as FIDs and Mass Spectrometers were capable of increased sensitivity though source/detector improvements Auto-analyzers were developed that could look at more analytes simultaneously from the same sample vial helping to conserve sample and provide better correlation of results During this Instrument Revolution, the newer technologies were also designed to reduce chemical interferences, background noise in detectors and increase the selectivity of target compounds 8 Right Solutions Right Partner

9 Things Are Getting Cleaner Sample container providers dramatically improved their cleaning and proofing protocols helping eliminated sample bottle contamination and the need for pre-rinsing Labs developed better Clean Room environments and enhanced cleaning processes and preparation options where possible to reduce the chance of lab background Labs developed in-bottle extraction techniques, and searched for ways to limit the need to manipulate the sample/extract more than absolutely necessary Labs looked at using less sample for extractions or digestions so as to limit the amount of co-extractives ending up in the final extracts for analysis and utilizing instrument sensitivity to reach the lower detection limits The labs looked to do more with less taking into account environmental and instrumentation limitations while trying to see lower levels 9 Right Solutions Right Partner

10 Groundwater Sampling 101 There are a number of physical factors that need to be considered when field sampling Sample coolers number of bottles per cooler, number of coolers per sampling event and number of wells to be sampled Developing wells processes to get the well prepared for sampling Sample acquisition bailing water and dispensing into bottles under field conditions Field Filtering for dissolved parameters Field Preservation to stabilize the chemical composition of the sample Quality Control taking field replicates and generating field blanks Sample Volume ensuring enough to fill all of the containers When there is an abundance of water in the well, there are typically few issues with the sampling event - and the meeting detection limit objectives When there is a lack of water available, that is when things gets challenging 10 Right Solutions Right Partner

11 Water Sampling in Low Flow Wells There are a number of challenges associated with Low-Flow Wells You need to take multiple bailers of sample, taking more time and potentially agitating sediment Increased sediment means increased filtering time for dissolved parameters You may not be able to completely fill all of the bottles potentially resulting in elevated detection limits or data gaps in reports You may not get enough water to properly take field QC (like replicates) where required by your program You may not have good field reproducibility with your replicates 11 Right Solutions Right Partner

12 Miniaturization One Answer to Low-Flow Conditions Requiring smaller sample volumes presents a number of measurable advantages: Depending on the parameters, you could fill all of the containers with one bailer of sample limiting well disturbance, and potential sediment intrusion The time to sample the well can be reduced by not needing to acquire multiple bailers of water With less sediment, field filtering is faster and can be done with less filters You can acquire enough sample for field replicates It will ultimately take less water to fill all of the containers 12 Right Solutions Right Partner

13 Doing More With Less ALS in Australia made the decision to make miniaturization a priority as a Global Initiative We began the journey to reducing sample sizes of a large cross section of tests starting with Australia and rolled out those improvements in Canada In 2011, ALS won a National Award for Innovation and Sustainability for Environmental Protection and Stewardship 13 Right Solutions Right Partner

14 Miniaturization Advantages - Safety Factors When you need less water sample to perform field sampling, a number of Safety Improvements can be realized You reduce the chance of repetitive motion injury from field filtering samples (less sediment = less filtering) You need less preservative reducing exposure to acids/stabilizing chemicals You can use smaller coolers to sample the same amount of wells allowing safer movement site-to-site You can end up with significantly less weight once the sampling is completed - helping to mitigate back strain from handling heavy coolers 14 Right Solutions Right Partner

15 Quality Factors When you need less water sample to perform field sampling, a number of Quality Improvements can be realized You can get enough sample for field replicates allowing the opportunity to measure sampling reproducibility You reduce the risk of introducing sediment intrusion through multiple bailing, and thereby reduce the chance of false positives By reducing the need to do multiple bails, you get more representative water chemistry (sample continuity) across all sample containers - including replicates The first and last containers you fill will have more consistent chemical properties as compared to re-visiting the well multiple times 15 Right Solutions Right Partner

16 Economic Factors When you need less water sample to perform field sampling, a number of Economic Improvements are realized Less time re-charging a well can result in lower development cost Less time acquiring sufficient water can result in lower sampling cost Less time filtering in the field can result in lower manpower cost Less use of filter cartridges can result in lower consumable cost Less weight of sample coolers can result in lower shipping costs 16 Right Solutions Right Partner

17 Environmental Factors Through the reduction in bottle sizes, positive Environmental Impacts have been realized through the ALS network Thousands of Kilograms less waste has been sent to landfills Over 10 tons of CO2 emissions have been reduced annually Less solvents and acids for sample preservation and preparation meaning less hazardous waste to manage Environmental Stewardship has been realized and shared with clients as a positive outcome to the miniaturization process 17 Right Solutions Right Partner

18 Examples of Bottle Miniaturization - Metals Bottle reduction from 250mL/125mL down to 60mL State of the art equipment Collision Cell/Reaction Cell ICP/MS technology Sample digestion procedures were micro scaled by 5x Rigorous proofing processes were undertaken to ensure the 60mL bottles were clean and fit for purpose The amount of preservative required was reduced 18 Right Solutions Right Partner

19 Mercury Bottle reduction from 125mL bottle to 40 ml vial New technology allows the lab to meet the AB Tier 1 surface water criteria from a 40mL glass vial Bottle reduction from 250mL down to 125mL for Ultra Trace Hg/ Methyl Hg through investing in the latest automated analyzer technologies Optimized sample volume usage control and sample conservation practices were also improved 19 Right Solutions Right Partner

20 F24/EPH/PAHs Bottle reduction from 250mL down to 100mL All three chemistries can be extracted from the same container Simultaneous in-bottle extraction limits handling and exposure to potential contamination from laboratory glassware or processes We now utilize large Volume Injection on the GC/FID and GC/MS Higher sensitivity FID and MS in newer instruments 20 Right Solutions Right Partner

21 Cyanide Bottle Reduction from 125mL down to 60mL Manual macro distillations used to be 500mL per run years ago Smaller manual distillations of 25-50mL per run were used later on Now automated in-line UV digestion uses only 5mL per run 5-10x less sample over historic requirements New automated systems have less interferences from other substances such as thiocyanate 21 Right Solutions Right Partner

22 Nutrients Bottle Reduction from 250mL down to 125mL Classic digestions for nutrients have been scaled down Digest volume for TP, TN, TKN have all been scaled back Careful control of sample volumes utilized has also resulted in less sample needed TOC, TC, COD, NH3 can come from the same bottle as well Through investment in automation 22 Right Solutions Right Partner

23 VOCs/BTEX/F1 in water Container reduction from 3 x 40mL vials down to 2 x 40mL We used to need 3 vials because of Purge & Trap Technology as you needed a whole vial for each run that was made The P&T autosampler was problematic and prone to issues such as carry over and breaking down so backup vials were a necessity Went to using headspace technology more rugged and dependable More runs/vial were now possible 23 Right Solutions Right Partner

24 Water Soluble and Thermally Labile Compounds Bottle reduction from 1L to 60mL Includes PFOS/PFOA, Steroids, Sulfolane, Paraquot/Diaquot, Aldicarb, Diuron, PPCP, Glyphosate and AMPA Latest state of the art LC/MS/MS (triple quad LC/MS) with higher sensitivity, selectivity and resolution than older models Use of direct sample injection no sample prep thus eliminating the need for sample extraction and solvent reduction Carefully evaluated minimum sample requirements to make sure MDL requirements could be met 24 Right Solutions Right Partner

25 Validity of Testing These are just some of the changes to bottle size that have been validated and implemented within the last year, and other examples have been happening over time as required to meet detection limit objectives All of the analytical method improvements have undergone significant ruggedness testing and are ISO Accredited at each lab where the tests are run All of the bottle changes listed in this presentation have been rolled out Canada-wide so that clients can take advantage of the improvements when sampling 25 Right Solutions Right Partner

26 Summary In summary, the advantages of miniaturization include: Safety (cooler size/weight, preservative volume, repetitive motion) Economics (lower shipping cost, less field consumables, less time sampling/resampling, less time field filtering, lower disposal costs) Quality (duplicates, water quality, reproducibility, reduce false positives, mitigate elevated detection limits) Environment (landfill/carbon footprint, less solvents, less preservatives, less overall waste) You really are able to do more with less 26 Right Solutions Right Partner

27 Insert Visual Aid Here They say a picture speaks a thousand words Old Containers New Containers Thank You Questions? 27 Right Solutions Right Partner