Protocol of Accepted…

Protocol of Accepted Drinking Water Testing Methods v03

1. 1.2.1 Accepted Reference Method; Sample Collection, Containers, Hold Times (& Appendix C). We suggest these sections should include guidance for when whole bottle extraction/analysis is required, particularly for laboratory duplicate requirements (e.g., organics extraction tests). Under these conditions, only field duplicates can be conducted, which should be covered by field quality control (QC) requirements submitted by clients. We suggest that it should not be a laboratory requirement to request extra bottles to conduct field QC (duplicates) for tests which require whole-bottle analysis, and where laboratory sub-sampling does not contribute to the variability of measurement.

2. 1.2.1.1 Accepted Modifications b) Modifying Sample Volume Requirements. Very few reference methods define limits for acceptable sample volumes; rather they tend to provide typical (historical) volumes used, as guidance only. We strongly suggest this section should be more open to innovation where smaller sample volumes can be demonstrated as suitable without data quality impacts, even if below volumes in published references. This is crucial because our labs are striving to be innovative to responsibly reduce consumable and energy waste, to minimize our climate change impacts in support of Net Zero goals. Reducing sample size is one of the most effective ways to minimize our climate change impacts and carbon footprint. Reductions in sample volumes should be permitted (if validated to meet all DQOs) unless there is a known and documented reason why a particular volume minimum is needed.

3. 1.2.2 Additional Criteria – Alternate Reference/In-house Methods c) Working and Linear Ranges. We suggest this section should state that non-linear calibrations (e.g., quadratic) are acceptable in many cases where linear calibrations do not meet requirements.

4. 1.2.2 Additional Criteria – Alternate Reference/In-house Methods f) Sample Containers, Preservative and Hold Times. Hold times, preservatives, and sample container material requirements are critical quality elements of lab testing protocols. We are appreciative of MECP’s support for the use of alternative references or in-house methods for these factors, but we feel very strongly that any such MECP-approved alternative guidance must be published and approved for use by all Ontario laboratories. It would be unacceptable for different labs to employ different or proprietary hold times / preservatives / container materials for competitive advantage without sharing this information for industry-wide use (after review/approval by MECP). We also strongly recommend for MECP to standardize to the greatest extend possible with preservative, hold time, and container material guidance from the Canadian Council of Ministers of the Environment (CCME) Volume 4-Analytical Methods-Environmental Site Characterization PN 1557 (2016), which incorporates industry best practices from a wide range of published references (as recommended by numerous Canadian government and commercial laboratory representatives on the committee that developed this guidance).

5. 2.1.3 Methods for Escherichia coli. This section includes a total coliform reference in error and is missing an acceptable reference for membrane filtration using mFC-BCIG agar for water. APHA does not have a reference method for mFC-BCIG either; We request to have LaSB method E3371 added as a reference to this section, since this is the only reference method, we are aware of which lists mFC-BCIG agar for water matrices.

6. 3.0 Chemical Parameters, General Statement Regarding Pesticides. Pesticides listed in this document only list parameters from O. Reg. 169/03; however, there are dozens of additional pesticide parameters that are reportable at 100 ng/L (or laboratory achievable LOR reporting limits). We strongly suggest additional clarity and information is required in this document for how to report pesticides for all laboratories. It is challenging to navigate through separate memos/bulletins and inspector/laboratory-specific discussions to ensure compliance.

7. 3.0 Chemical Parameters, 3.7 Polychlorinated Biphenyls (PCBs) and Trifluralin. We request that EPA Method 3511 (Organic Compounds in Water by Microextraction) is added to section 3.7 as a reference for PCB extractions. Method 3511 is applicable to numerous extractable organic compounds (predominantly semi-volatiles, but also some VOCs), and is a modern method which is widely used to support smaller water sample sizes (in support of climate change goals). Additionally, we request that LaSB method E3523 Determination of Multiresidue Pesticides in Water is added to section 3.7 as a reference for Trifluralin. MECP currently defines Total PCBs as the sum of only two (2) PCB Aroclors (1254 and 1260). The industry standard for Total PCBs across Canada uses as least the sum of the four (4) most common Aroclors (1242, 1248, 1254, and 1260; as per CCME 2016). BC MOECC requires inclusion of all nine (9) Aroclors for Total PCB (also endorsed, but not required, by CCME). We recommend for MECP to re-define Total PCBs to include at least 1242, 1248, 1254, and 1260, as per CCME guidance, and to consider using all nine. The same analytical method used to quantify two Aroclors can be used for all nine (i.e., also including Aroclors 1016, 1221, 1232, 1262, and 1268).

8. 3.0 Chemical Parameters, 3.9 Chlorophenols (CPs) and Phenoxy Acids (PAs). We request that EPA Method 3511 (Organic Compounds in Water by Microextraction) is added as an extraction method reference for Chlorophenols.

9. 3.0 Chemical Parameters, 3.10 Quaternary Ammonium Compounds. For clarity, we request inclusion within this section of an explanation for why CAS numbers for Diquat and Paraquat changed from v02 to v03 and confirming the required parameter definition for comparison against guidelines. Laboratory analysis protocols for Diquat or Paraquat “as cations” or “as dihalides” are the same, but reported concentrations differ significantly, so consistency with the parameter reporting convention among labs (and for comparison to guidelines) are critical.

10. 3.0 Chemical Parameters, 3.14 Benzo(a)pyrene. There are no extraction methods listed in this section. We request to have the following extraction reference methods added to section 3.14:
a. EPA Method 3511 (Organic Compounds in Water by Microextraction)
b. EPA Method 3510C (Separatory Funnel Liquid-Liquid Extraction)
c. EPA Method 3520C (Continuous Liquid-Liquid Extraction)
d. EPA Method 3535A (Solid Phase Extraction (SPE)

11. 3.0 Chemical Parameters, 3.15 Cyanide. We have been licensed for cyanide analysis for many years and is recognized in Canada (particularly within the mining sector) as a leader in cyanide chemistry. None of the reference methods we utilize for cyanide testing are listed in this section. We request to have the following reference methods added to section 3.15 (most importantly the first three):
a. ISO 14403.2 Water Quality- Determination of total cyanide [and free cyanide] using flow analysis (CFA) – Part 2 – Method with continuous flow analysis (CFA). Note: We use and endorse only the ISO 14403.2 method for Total Cyanide. The ISO 14403.2 method for “Free Cyanide” uses pH 3.8, which is actually WAD CN, not Free CN. We suggest this should be noted.
b. APHA 4500– I CN- Weak Acid Dissociable Cyanide.
c. ASTM D7237 -18 Standard Test Method for Free Cyanide and Aquatic Free Cyanide with Flow Injection Analysis (FIA) Utilizing Gas Diffusion Separation and Amperometric Detection.
d. APHA 4500-CN– P. Total Cyanide by Segmented Flow Injection, UV-Irradiation with Gas Diffusion, and Amperometric Measurement.

12. 3.0 Chemical Parameters 3.17 Nitrilotriacetic Acid (NTA). We request that EPA Method 430.1 be added to section 3.15. Methods 430.1 and 430.2 represent the same method principles; 430.1 is the manual version, and 430.2 is the automated version. MECP currently endorses a 30-day hold time for NTA (unpreserved) in drinking waters. We suggest that a 30-day hold time for NTA is unlikely to be defensible, even for drinking waters. There is ample published literature on NTA that indicates it to be rapidly biodegradable, with quoted half-lives in environmental samples ranging from hours to a few days (US EPA, WHO). We suggest the NTA hold time for unpreserved samples should be significantly reduced. Historical US EPA hold time guidance for unpreserved NTA (EPA-600/4-79-020) is 24 hours. BC MOECC uses 24 hours for unpreserved NTA, or 14 days with acid preservation (sodium bisulfate; NaHSO4). Stability is likely longer in drinking waters than in many environmental waters, but 30 days seems excessive. We would support a much shorter unpreserved hold time, and an option for a 14-day preserved hold time (as per BC).

13. 3.0 Chemical Parameters 3,1.9 Bromate, Chlorate and Chlorite. We request that EPA Method 557 Determination of Haloacetic Acids, Bromate and Dalapon in Drinking Water by Ion Chromatography Electrospray Ionization Tandem Mass Spectrometry (IC-ESI-MS/MS) is added to section 3.19 for Bromate.

14. Appendix C MECP Sample Collection and Handling Requirements. We are respectfully opposed to MECP’s focus on sample container sizes. Sample container sizes should be left to the discretion of individual laboratories, with validation required to demonstrate performance objectives are met, except in cases where container size is known to be important, or is stipulated in a regulation (e.g., O. Reg 243/07 Schools, Private Schools, and Child Care Centres). By listing and requiring arbitrary volumes, MECP is setting up roadblocks to prevent laboratories from addressing Net Zero and climate change goals and obligations. Where there is no specific reason for a sample volume requirement, can Appendix C list “typical ranges” rather than volume requirements? For our hold time concerns, refer to our No. 4 comment above. Can the storage conditions column be clearer by adding which samples can’t be analyzed if frozen?
a. Mercury comments. MECP should be aligned with CCME for container and preservative. Ontario as led the industry in Canada in requiring only glass and Teflon for Hg in water. HNO3 preservation should not be allowed. Hg in water is highly unstable when unpreserved (or even HNO3 preserved), especially in plastic. Potassium dichromate should not be recommended due to toxicity of Cr6. Field preservation with HCl and/or lab preservation with BrCl should be preferred as per EPA 1631E.
b. Nitrate/Nitrite comments. Why has this container size increased? Anions are typically sampled in the same container and analyzed together; however, this section utilizes different container sizes per anion.
c. Various Pesticides/Organics comments. Several pesticides can be sampled in the same containers; however, this section utilizes different containers per parameter group. Additionally, the hold times are variable as well. CCME references for hold times for BNAs, CPs, OCs, PAH, pesticides, and herbicides are 14 days prior to extraction and 40 days after extraction. We suggest that MECP should align with CCME for container, preservatives, and hold times, to be consistent with industry standards.
d. Benzo(a)pyrene comments. We request to have sodium bisulfate added as another option for a preservative. We were granted permission by MECP inspector in 2023 to switch from sodium thiosulfate to using sodium bisulfate.

Practices for the Collection and Handling of Drinking Water

1. 3.3 Sample Containers Sample Volume. As previously stated, we feel strongly that more flexibility should be allowed for sample container sizes / minimum volumes. We wholly agree that suitable container materials need to be approved based on science (e.g., adsorption or contamination potential). But sample volume requirements are normally only a function of the lab’s analytical method, except where a minimum volume must be collected for defined reasons (e.g., lead sample volume requirements under O. Reg 243/07 Schools, Private Schools, and Child Care Centres). Barring known and defined reasons to require specific minimum volumes, we recommend for labs to be allowed to establish and validate sample volumes that meet defined quality criteria with their methods. The second paragraph of this section discusses Travelling Blanks (aka Trip Blanks), however the definition used is inconsistent with the industry standard. Field Blanks (in various forms) are prepared in the field and exposed to field conditions. Trip blanks are normally prepared by the laboratory and are kept sealed to assess only the impact of transportation. We recommend Field Blanks instead of Trip Blanks where possible, since Field Blanks assess more elements of the sampling process (including transportation, but also including the same batch of containers and preservatives used with samples and including the sampling environment). The simplest form of Field Blank is where the sampler dispenses reagent water (typically provided by the lab) into a sample container in the field, which we recommend (Equipment Blanks are better still).

2. 3.4.2 Sample Filtering. We understand why field filtering is in principle not permitted for drinking waters; however, we request MECP to allow filtering prior to analysis for water soluble ionic substances (e.g., nitrate, nitrite, fluoride), where filtration does not affect the parameters or analysis in any way, but where particulate in the sample may cause analytical interference or even damage to sensitive instruments. Currently if a sample contains high levels of particulate, laboratories must notify that analysis can’t be provided for anions required by regulation O. Reg. 170/03.
 
3. 3.4.3 Sample Preservation, pH control. We respectfully disagree with the 2nd paragraph of the pH control section, which indicates that strong acids should not be pre-charged in sample containers as preservatives (e.g., for metals). This is inconsistent with the industry standard for metals preservation in Ontario. We suggest that the best practices for preservation of metals are either field preservation using pre-charged containers, or lab preservation (as per CCME 2016 and EPA 200.8), where nitric acid is added at the lab within 14 days of sampling. Lab preservation is recommended by EPA 200.8, because it avoids TDG issues and potential hazards of strong acids in the field). We strongly recommend that both options be permitted. For ultra-trace level metals, lab preservation may sometimes be preferable, because it avoids potential leaching of trace-level metals from the container by the pre-charged acid. Any preservation technique applied by a lab should be validated to ensure suitability for the lab’s Limits of Reporting. A requirement for field preservation using separate acid vials adds safety and contamination risks and increases cost and disposable plastic waste with no benefits compared to the other options above.

4. 3.4.4 Sample Holding Times. We note that most North American jurisdictions use 30 hours as the maximum hold time for microbiology samples, based on APHA 9060, whereas MECP uses 48 hours. For microbiology tests with such critical health consequences, we would recommend adopting the industry standard 30-hour hold time, unless MECP is aware of peer-reviewed literature supporting the current 48-hour hold time. We also suggest that hold times longer than 60 days (where supported by reference literature – e.g., metals) are entirely valid and useful, not because they promote delays in testing, but because they permit valid and defensible confirmatory testing in the event of data integrity questions. We recommend adoption of industry-standard hold times (e.g., as endorsed by CCME / EPA / APHA / etc.), which promotes consistency among different regulations and provinces.

5. 3.5.1 Volatile Organic Compounds (VOCs). The first paragraph of this section should state that septa caps are intended to prevent evaporative loss of volatiles. To the best of our knowledge, very few labs still use autosamplers that directly sample from VOC vials. This section also mentions Travel Blanks. We suggest a recommendation that Field Blanks should be used in preference to Travel/Trip Blanks, because Field Blanks control more variables and are more representative of the sampling and transport processes used for samples.