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Home My WebLink About#5455 - 05 -2011 - FINALWMI To be attached to all inspection reports in-house only. Laboratory Cert. #: 5455 Laboratory Name: Town of Denton WWTP Inspection Type: Field Municipal Maintenance Date Report Completed: June 3, 2011 Date Forwarded to Reviewer: June 3. 2011 Date Review Completed: June O.2D11 Date Forwarded to Alberta-, 6/13/2011 -Bev' -Fly 'Eaves Perdu,- Gut=error June 13, 2011 5455 Mr. Troy Branch Town of Denton WWTP P.O. Box 306 Denton, NC 27239 SUBJECT: North Carolina Wastewater/Groundwater Laboratory Certification (NC WW(GW LC) Maintenance Inspection Dear Mr. Branch: Dee __ -} e> a» �zec` e* ar'( Enclosed is a report for the inspection performed on May 5, 2011 by Chet Whiting. Where finding(s) are cited in this report, a response is required. Within thirty days of receipt, please supply this office with a written item for item description of how these finding(s) were corrected. If the finding(s) cited in the enclosed report are not corrected, enforcement actions may be recommended. For certification maintenance, your laboratory must continue to carry out the requirements set forth in 15A NCAC 2H .0800. Copies of the checklists completed during the inspection may be requested from this office. Thank you for your cooperation during the inspection. If you wish to obtain an electronic copy of this report by email, or if you have questions or need additional information please contact me at 828-296-4677. Sincerely, Gary Francies Unit Supervisor Laboratory Section CC: Chet Whiting Gary Francies Master File NR . r a o a r. S i. VC L,ab'1`a. r L) 1 .�e n e Reedy Creef R _, R_ , _yJ_._...E: �.}s+� ;�ri .�72,v %L , Ci: ., Y. S v.ici,`,; '� a LABORATORY NAME: NPDES PERMIT #: ADDRESS: CERTIFICATE #: DATE OF INSPECTION: TYPE OF INSPECTION: AUDITOR(S): LOCAL PERSON(S) CONTACTED: INTRODUCTION: On -Site Inspection Report Town of Denton MVTP NCO026689 P.O. Box 306 Denton, NC 27239 5455 May 5, 2011 Field Municipal Maintenance Chet Whiting Troy Branch This laboratory was inspected to verify its compliance with the requirements of 15A NCAC 2H .0800 for the analysis of environmental samples. GENERAL COMMENTS: The facility is neat and well organized and has all the equipment necessary to perform the analyses. Benchsheets are well designed, easy to follow and concise. Documentation A. Finding: The laboratory needs to increase the documentation of purchased materials and reagents, as well as, documentation of standards and reagents prepared in the laboratory. Requirement: All chemicals, reagents, standards and consumabies used by the laboratory must have the following information documented: Date Received, Date Opened (in use), Vendor, Lot Number, and Expiration Date. A system (e.g., traceable identifiers) must be in place that links standard/reagent preparation information to analytical batches in which the solutions are used. Documentation of solution preparation must include the analyst's initials, date of preparation, the volume or weight of standard(s) used, the solvent and final volume of the solution. This information as well as the vendor, manufacturer, lot number, and expiration date must be retained for chemicals, reagents, standards and consumables used for a period of five years. Consumable materials such as pH buffers and lots of pre -made standards are included in this requirement. Ref: Quality Assurance Policies for Field Laboratories. General Laboratory: B. Finding: Auto-pipettors are not calibrated at least every 12 months. Requirement: Mechanical volumetric liquid -dispensing devices (e.g., fixed and adjustable auto- pipettors, bottle -top dispensers, etc.) must be calibrated at least every twelve months and documented. Each liquid -dispensing device must meet the manufacturer's statement of accuracy. For variable volume devices used at more than one setting, check the accuracy at the maximum, page 2 #5455 Town of Denton WWTP middle and minimum values. Testing at more than three volumes is optional. When a device capable of variable settings is dedicated to dispense a single specific volume, calibration is required at that setting only. Ref: Quality Assurance Policies for Field Laboratories.Technical Assistance Document Attached C. Finding: Proficiency Testing (PT) samples are not analyzed in the same manner as environmental samples. Requirement: The analysis of PT samples is designed to evaluate the entire process used to routinely report environmental analytical results. Therefore, PT samples must be analyzed in the same manner as environmental samples. Ref: Quality Assurance Policies for Field Laboratories. pH — Standard Methods, 18rh Edition, 4500 H+ P D. Finding: Each analyst does not always initial the pH bench sheet. Requirement: Data pertinent to each analysis must be maintained for five years. Certified Data must consist of date collected, time collected, sample site, sample collector, and sample analysis time. The field benchsheets must provide a space for the signature or initials of the analyst, and proper units of measure for all analyses, Ref: 15A NCAC 2H .0805 (7) (g) (1) Comment: At the time of the inspection the conductivity calibration standard exceeded the manufacturer expiration dates (expire April 2011), Quality Assurance Policies for Field Laboratories states: Adherence to manufacturer expiration dates is required. Chemicals, reagents, standards, consumables exceeding the expiration date can no longer be considered reliable. If the expiration is only listed as a month and year (with no specific day of the month), the last day of the month will be considered the actual date of expiration. Monitor materials for changes in appearance or consistency. Any changes may indicate potential contamination and the item should be discarded, even if the expiration date is not exceeded. If no expiration date is given, the laboratory must have a policy for assigning an expiration date. If no date received or expiration date can be determined, the item should be discarded. Appropriate corrective action had been taken, a purchase order for a replacement standard was on file. Comment: The check standard was still within the expiration date (May 13, 20131). •.• •a 0 0' The paper trail consisted of comparing field testing records and contract lab reports to Discharge Monitoring Reports (DMRs) submitted to the North Carolina Division of Water Quality. Data were reviewed for (NPDES permit # NC0026689) for January, February and March, 2011. No transcription errors were detected. The facility appears to be doing a good job of accurately transcribing data. V. CONCLUSIONS: Correcting the above -cited findings will help this lab to produce quality data and meet certification requirements. The inspector would like to thank the staff for its assistance during the inspection and data review process. Please respond to all findings. Report prepared by: Chet Whiting Date: June 3, 2011 Report reviewed by: Todd Crawford Date: June 6, 2011 Calibration of Mechanical Volumetric Liquid -Dispensing Devices Procedure A laboratory may use the following method for the gravimetric determination of measurement error of mechanical volumetric liquid -dispensing devices (e.g., fixed and adjustable auto-pipettors, bottle -top dispensers, etc.) used to dispense volumes greater than or equal to 100 pl. Apparatus and Equipment Weighing vessel (of sufficient capacity to hold all volumes dispensed for the test and a 3:1 height -to -diameter ratio is recommended to minimize evaporation) Reagent water (e.g., distilled or deionized water) Analytical balance (accurate to 0.0001 g for 100 pl to 10 ml, and accurate to 1 mg for 10 ml to 200 ml dispensed volumes) Calibrated thermometer (graduated, at a minimum, in 0.5 °C increments) Documentation Requirements Date Analyst's signature or initials Device identification (if there is no unique identification such as serial number, assign a laboratory identification) Temperature of the reagent water Nominal or test volume Weights of dispensed volumes Procedure 1. Allow apparatus and reagent water to equilibrate to room temperature. 2. Check the calibration of the balance. 3. Wet the liquid -dispensing device and lubricate the piston insuring smooth operation by pipetting several volumes to waste. 4. Weigh the vessel and tare the balance. 5. Dispense a minimum of five aliquots of water into the vessel, weighing and recording the mass for each replicate. 6. Calculate the following: m = mean mass = total of individual weight measurements total number of measurements Z = Z correction factor obtained from Table 1 using the temperature of the test liquid and current barometric pressure. V = volume equivalent (or corrected volume) of mass measured = m x Z RE = relative error (%) = Vm - Volx 100 Vo where: Vm = corrected mean volume = total of corrected volumes total number of dispensed volumes Vo = nominal or test volume Page 2 of 3 Calibration of Mechanical Volumetric Liquid -Dispensing Devices Procedure S = standard deviation = For each replicate, subtract the mean volume from the corrected volume, then square the value. Sum the squared values of all replicates, and then divide the sum by n-1 (the number of measurements minus 1). Take the square root of this value to get the standard deviation. CV = coefficient of variation (%) = s x 100 Vm To simplify this process, spreadsheets for calculating and documenting the relative error and coefficient of variation can be found on the NC Wastewater/Groundwater Laboratory Certification (NC WW/GW LC) website at httQ://h2o.enr.state.nc.us/lab/download.htm. The Relative Error (a measure of accuracy) and Coefficient of Variation (a measure of precision) must not be greater than the manufacturer's specifications. If the results are greater than the manufacturer's specification, repeat the procedure. If the results remain greater, follow the manufacturer's instructions for maintenance and adjustment and repeat the procedure. If repeated calibration attempts do not yield results within the manufacturer's specifications, the liquid -dispensing device must be repaired or replaced. Note: Microliter pipettors may need to be tested under more rigorously controlled conditions or sent to a calibration service for testing. Since most analytical balances used in environmental laboratories read to only four decimal places, it may be necessary, when checking microliter pipettors (less than 1000 pl), to include the weight of the weighing vessel in each replicate and subtract it and subsequent aliquots out manually in order to have a measurable mass for the purpose of this verification. Contact your auditor if you have questions. Rev. 03/2009 Page 3 of 3 Calibration of Mechanical Volumetric Liquid -Dispensing Devices Procedure Table 1. Z Correction Factor Table. Temperature Air pressure, kPa (mbar) °C 80 (800) 85 (850) 90 (900) 95 (950) 100 (1000) 101.3 (1013) ( 105 (1050) j 15.0 1.0017 1.0018 1.0019 1.0019 1.0020 1.0020 1.0020 15.5 1.0018 1.0019-1 1.0019 1.0020 1.00 0 1.0020 _ 1.0021 16.0 1.0019 1.0020 1.0020 1.0021 1.0021 1! 1.0021 1.0022 _ 16.5 1.0020 1.0020 ; 1.0021 1.0021 1 1.0022 1.0022 1.00_22 ! j 17.0 1.0021 1.0021 1.0022 1.0022 1.0023 1 1.0023 1.0023 17.5 1.0022 1.0022 1.0023 1.0023 1.0024 _j� 1.0024 1.0024 18.0 1.0022 j 1.0023 1.0023 1.0024 1.0025 1.0025 1.0025 18.5 1.0023 1.0024 1.0024 1.0025 1.0025 1.0026 1.0026 19.0 1.0024 1.0025 1.0025 j 1.0026 1.0026 1.0027 1.0027 _ 19.5 1.0025 _ 1.0026 1.0026 1.0027 1.0027 1.0028 1.0028 20.0 1.0026 1.0027 1.0027 1.0028 1.0028 1.0029 1.0029 20.5 1.0027 1.0028 1.0028 1.0029 1.0029 1.0030 ; 1.0030 21.0 1.0028 1.0029 1.0029 1.0030 1.0031 1.0031 1 1.0031 21.5 1.0030 1.0030 1.0031 1.0031 1.0032 1.0032 1.0032 22.0 1.0031 1.0031 1.0032 1.0032 1.0033 1 1.0033 1.0033 22.5 1.0032 1.0032 1.0033 1.0033 1.0034 j 1.0034__ 1.0034 23.0 1.0033 1.0033i 1.0034 1.0034 1.0035 11.0035 1.0036 23.5 24.0 24.5 1.0034 1 1.0035 1.0037 1.0035 _) 1.0036 1.0037 1.0035 1.0036 1.0038 1.0036 _ } 1.0037 1.0038 1.0036 1.0037 1.0039 1.0036 1.0038 1.0039 1.0037 1.0038 1.0039 25.0 1.0038 1.0038 1.0039 1. 0039 _ 1.0040 1.0040 _ 1. 0040 25.5 1.0039 1.0040 1.0040 1.0041 1 1.0041 1.0041 1.0042 26.0 26.5 27.0 27.5 28.0 1.0040 1.0042 1.0043 1.0045 1.0046 1.0041 1.0042 1.0044 1.0045 1.0046 1.0041 1.0043 1.0044 1.0046 1.0047 1.0042 1.0043 1.0045 1.0046 1,0047 1.0042 1.0044 1.0045 1.0047 1.0048 1.0043 1.0044 { 1-0045 1.0047 1.0048 1.0043 1.0044 1.0046 1.0047 1. 0048 28.5 1.0047 1.0048 1.0048 1.0049 1.0049 1.0050 1.0050 29.0 1.0049 1.0049 1.0050 1.0050 1.0051 1.0051 1.0051 29.5 1.0050 1.0051 1.0051 1.0052 1.0052 1.0052 1.0053 30.0 1.0052 1.0052 1.0053 ; 1.0053 1.0054 1.0054 1.0054 Z correction factors are for distilled water as a function of liquid test temperature and air pressure. Z values are in microliters per milligram. Reprinted from ISO 8655-6:2002(E). If your laboratory does not have a mercury barometer, the true local barometric pressure for locations throughout North Carolina may be obtained from the North Carolina State University, State Climate Office of North Carolina website at http:/Iwww.nc-climate.ncsu.edu/.