NC DENR/DWQ WASTEWATER/GROUNDWATER LABORATORY CERTIFICATION

Transcription

1 NC DENR/DWQ WTEWTER/GRUNDWTER RTRY CERTIFICTIN RTRY NME: CERT #: RIMRY NYT: DTE: NME F ERN CMETING CHECKIT (RINT): IGNTURE F ERN CMETING CHECKIT: EQUIMENT: Filtration apparatus suitable for the filter disk selected. Circle type used: 1. Membrane filter funnel 2. Gooch crucible, 25 ml to 40 ml capacity, with Gooch crucible adapter 3. Filtration apparatus with reservoir and coarse (40- to 60- µm) fritted disk as filter support luminum weighing dishes Drying oven, for operation at 103 to 105 ºC arameter: Total uspended olids (queous) Method: tandard Methods 2540 D-1997 uditor s Guide Glass fiber filter disks without organic binder (ractical filter diameters are 2.2 to 12.5 cm). Circle Type Used: Whatman grade 934H Gelman type /E Millipore type 40 E-D cientific pecialties grade 161 Environmental Express ro Weigh pre-weighed ther that gives demonstrably equivalent results (list): Desiccator, provided with desiccant containing a color indicator of moisture concentration or an instrumental indicator uction flask, of sufficient capacity for sample size selected Reagent grade water nalytical balance, capable of weighing 0.1 mg ( g) Graduated cylinder Magnetic stirrer with TFE stirring bar (not required) Flat tipped forceps (recommended) eakers Wide-bore pipets (Kimble Nos or or equivalent) (not required) Computer equipped with roweigh software and bar code reader EE CMETE CHECKIT IN INDEIE INK lease mark Y, N or N in the column labeled to indicate the common lab practice and in the column labeled to indicate whether it is addressed in the. 1 GENER What is the most recent review/revision date of the? [15 NCC 2H.0805 (a) (7)] Date: 2 Is there North Carolina data available for review? If not, review T data REERVTIN and TRGE re samples iced to above freezing but 6 º C during shipment? [40 CFR Table II] re samples refrigerated above freezing but 6 ºC during storage? [40 CFR Table II] re samples analyzed within 7 days of collection? [40 CFR Table II] RCEDURE Filter reparation re pre-prepared (i.e., commercially pre-weighed) filters being used? [M 2540 D (3) (a)- If YE, skip to question #14 EXNTIN Verify proper method reference. Recommend an annual review. Update s any time changes are made to procedure and make a list or highlight any changes that were made to methodology. EXNTIN 40 CFR footnote 2 allows 15 minutes for sample preservation, including thermal. This means that if a sample is received in the lab within 15 minutes it is not required to be on ice. Document temperature downward trend for short transport samples. EXNTIN If pre-prepared (i.e., commercially preweighed) glass fiber filters disks are used, eliminate washing filters. It also eliminates

2 Total uspended olids (uditors Guide) age 2 the need to weight to constant weight Is the glass fiber filter being placed in the filter funnel or Gooch crucible wrinkle side up during filter preparation? [M 2540 D (3) (a)- Is the laboratory washing the filter with at least 3 successive 20 m portions of reagent grade water? [M 2540 D (3) (a)- Is filter suctioned to remove all traces of water? [M 2540 D (3) (a)- t what temperature is the prepared filter, aluminum weighing dish or Gooch crucible being dried? [M 2540 D (3) (a)- rior to sample analysis, is the laboratory drying, cooling, desiccating, and weighing filters until a constant weight is obtained or until weight change is less than 4% of the previous weighing or 0.5 mg, whichever is less? [M 2540 D (3) (a)- If the filters are not weighed to a constant weight prior to sample analysis, is a dried filter (i.e., filter blank) verified to constant weight each day samples are analyzed? [NC WW/GW C olicy] re dried filters being stored in a desiccator? [M 2540 D (3) (a)- RCEDURE- ample nalysis 14 re samples well mixed prior to analysis? [M 2540 D (3) (c)- Insert disk with wrinkled side up in filtration apparatus or Gooch crucible. pply vacuum and wash with at least 3 successive 20 m portions of reagent grade water. Continue suction to remove all traces of water, turn vacuum off and discard washings. Remove filter from filtration apparatus and transfer to an inert aluminum weighing dish. If a Gooch crucible is used, remove crucible and filter combination. Dry in an oven at 103 to 105 ºC for 1 h. Cool in desiccator to balance temperature and weigh. This is part of the filter preparation before sample analysis. Repeat cycle of drying or igniting, cooling, desiccating and weighing until a constant weight is obtained or until weight change is less than 4% of the previous weighing or 0.5 mg ( g), whichever is less. Do not filter water through this filter. ost analysis weight (weighed with samples after drying) must be within 4% of the previous weighing or 0.5 mg ( g); whichever is less. This fulfills the initial drying cycle verification required by the method. tore prepared filters in an adequately sealed (i.e., grease, vacuum, seals in good shape) desiccator until needed for sample analysis. Each sample requires close attention to desiccation after drying. Minimize opening desiccator because moist air enters. ome samples may be stronger desiccants than those used in the desiccator and may take on water. Residues dried at 103 to 105 ºC may retain not only water of crystallization but also some mechanically occluded water. EXNTIN amples may be mixed by shaking in sample bottle or stirring with magnetic stirrer. Wide-bore pipet or graduated cylinder. Use of a graduated cylinder is considered the practical means to measure sample volume. Multiple draws with a pipet are not considered practical. 15 How is the sample volume measured? [M 2540 D (2)- If using graduated cylinder to measure sample volume, good laboratory practice is to rinse the graduated cylinder with reagent grade water after filtering sample. Rinsings are then filtered. Method states: tir sample with a magnetic stirrer at a speed to shear larger particles, if practical, to obtain a more uniform, (preferably homogenous) particle size. Centrifugal force may separate

3 16 Did sample volume yield the required residue: 2.5 to 200 mg? [M 2540 D (3) (b)- 17 What is the reporting limit (Q)? [M 2540 D (4) What is the maximum filtration time allowed to filter samples? [M 2540 D (3) (b)- Is filter placed with wrinkled side up during sample filtration? [M 2540 D (3) (a)- Is filter being seated with reagent grade water prior to filtering sample? [M 2540 D (3) (c)- re sample filters being washed after sample transfer? [M 2540 D (3) (c)- re samples allowed to drain completely between washings? [M 2540 D (3) (c)- How are samples transferred to the drying oven? [M 2540 D (3) (c)- t what temperature is the sample being dried? [M 2540 D (3) (c)- re the start/end times of the drying documented? [15 NCC 2H.0805 (a) (7) ()] Total uspended olids (uditors Guide) age 3 particle by size and density, resulting in poor precision when point of sample withdrawal is varied. While stirring, pipet a measured volume onto the seated glass fiber filter. For homogeneous samples, pipet from the approximate midpoint of container but not in vortex. Choose a point both mid-depth and midway between wall and vortex. Choose sample volume to yield between 2.5 and 200 mg dried residue. If volume filtered fails to meet minimum yield, increase sample volume up to mg/ if 1000 m sample volume is used. The minimum reporting value is determined by a minimum weight gain requirement of 2.5 mg and the volume of sample analyzed. In instances where the weight gain is less than the required 2.5 mg, the value must be reported as less than the appropriate value based upon the volume used. For example, if 100 m of sample is analyzed and < 2.5 mg of dried residue is obtained, the value reported would be < 25 mg/. Reporting limit must be low enough to demonstrate compliance. Verify reporting limit on final reports or DMR to insure accuracy and appropriate adjustment by IM or lab personnel. If complete filtration takes more than 10 min, increase filter diameter or decrease sample volume. rolonged filtration times resulting from filter clogging may produce high results owing to increased colloidal materials captured on the clogged filter. Insert disk with wrinkled side up in filtration apparatus. This is so the filter sits flat on the funnel or crucible and the residue is retained on the filter. NTE: Examine lock/sealing mechanism on filter funnels to insure there is no leakage or loss of sample residue under the filter. ssemble filtering apparatus and begin suction. Wet filter with a small volume of reagent-grade water to seat it. Wash filter with three successive 10-ml volumes of reagent-grade water. llow complete drainage between washings, and continue suction for about 3 min after filtration is complete. amples with higher dissolved solids may require additional washings. Incomplete filtration may result in the wet filter sticking to the weighing dish during drying. Carefully remove filter from filtration apparatus and transfer to an aluminum weighing dish as a support. lternatively remove the crucible and filter combination from the crucible adapter if a Gooch crucible is used. lthough the method does not indicated how to remove filter it is recommended that flat tip forceps be used. Dry for at least 1 hr at 103 to 105 ºC in an oven. Time in and out of oven if oven is preheated to proper temperature. If oven is not at proper temperature when samples are put in must document actual

4 re samples being cooled in a desiccator after drying, until they reach ambient temperature? [M 2540 D (3) (c)- Is the desiccator equipped with an instrumental indicator (humidity gauge), color indicating desiccant, or both? [M 2540 D (2)- Is the laboratory using an analytical balance that is capable of weighing at least 0.1 mg ( g)? [M 2540 D (2)- Is the analytical balance mounted on a shock proof table? Is the analytical balance being serviced every 12 months by a qualified vendor/technician? [NC WW/GW C olicy] Does the laboratory have documentation to verify that the balance has been serviced? [NC WW/GW C olicy] Is the laboratory using Class or TM Class 1 and/or Class 2 weights? [NC WW/GW C olicy] re the weights being verified every 5 years? [NC WW/GW C olicy] Does the laboratory have documentation indicating that the weights were verified? [15 NCC 2H.0805 (a) (7) () and (G)] Total uspended olids (uditors Guide) age 4 time heated at proper temperature. This is considered pertinent information. Cool in a desiccator to balance temperature, and weigh. Desiccator must contain a color indicator of moisture content or an instrument indicator. M 2540 D. 2. References 2540 (2) (d). It is recommended that color indicating desiccant be used as a backup even when a humidity indicator is being used in the desiccator. Use an analytical balance capable of weighing 0.1 mg. 15 NCC.0805(a)(6)(D) requires an analytical balance on a shock proof table. We consider this Rule requirement met as long as the balance is: n a stable surface In a low traffic area Free from drafts You can check balance stability by walking near it or hitting surface gently with hand to see if balance is stable. aboratory analytical balance(s) must be serviced by a qualified vendor/technician at a minimum every 12 months to ensure that the balance is functioning within required tolerances. Documentation that this service has been performed must be available for review upon request. If the operational capabilities of the balance are in question at any time during the 12-month period, corrective action must be taken. TM Class 1 and Class 2 or NIT Class weights must be used in determining all mass determinations. TM Class 1 and Class 2 and NIT Class weights must be verified at least every 5 years. TM Class 1 (20 g to 25 kg) and Class 2 (10 g to 1 mg) weights are equivalent to the N Class weights specified in 15 NCC 2H.0805 (a) (7) (K). Verification may be accomplished by: 1. ending laboratory weights back to the manufacturer for recertification - reference weights shall be calibrated by a body that can provide traceability to TM specifications, or 2. Checking laboratory weights against certified reference weights (i.e., weights that have been recertified as above) and found to be within TM Type I tolerances (see Weight Verification policy) - often the balance service technician may provide this service. Date Verified: Documentation of weight verifications or recertification must be maintained for 5 years. If the condition of a weight(s) is in question at any time due to damage (e.g., corrosion, nicks, scratching, etc.), the laboratory must have that weight(s) re-

5 Total uspended olids (uditors Guide) age 5 verified as described above. 35 Is the balance checked with a weight each day of use? [15 NCC 2H.0805 (a) (7) (K)] 36 Is this documented? [15 NCC 2H.0805 (a) (7) () and (G)] 37 Is the balance checked with at least three weights quarterly? [15 NCC 2H.0805 (a) (7) (K)] 38 Is this documented? [15 NCC 2H.0805 (a) (7) () and (G)] Weight: Weights: Dates: 39 fter sample analysis, is the laboratory drying, cooling, desiccating and weighing sample filters until a constant weight is obtained or until weight change is less than 4% of previous weight or 0.5 mg? [M 2540 D (3) (c)- Repeat drying cycle of drying, cooling, desiccating and weighing until a constant weight is obtained or until weight change is less than 4% of the previous weight or 0.5 mg (0.0005), whichever is less. Date: 40 If not, when was the last annual drying time study performed? [NC WW/GW C olicy] QUITY CNTR 41 Is there documented traceability of consumables (e.g., filters)? What corrective actions are taken when interferences are observed? [M 2540 D (1) (b)-1997 and 15 NCC 2H.0805 (a) (7) (F)] Does the laboratory analyze duplicate samples at a rate of 10%? [M-2540 D (3) (c)- What is the acceptance criterion for duplicates? [M-2540 D (3) (c) and 15 NCC 2H.0805 (a) (7)] What corrective action does the laboratory take if the duplicate samples results are outside of established control limits or method accuracy limits? [15 NCC 2H.0805 (a) (7) (F)] Is a check standard being analyzed quarterly? [15 NCC 2H.0805 (a) (7) ()] 47 What type of standard is being used? [15 NCC 2H.0805 (a) (7) ()] amples representing each matrix type encountered by the laboratory must be included in the annual study. Verify minimum daily drying time is equal to or greater than the time used for the initial verification study drying cycle. ubsequent drying cycles must be a minimum 1 hour for verification. Check documentation of time in/out of oven. EXNTIN Traceability documentation for any filters would include vendor, lot #, and date put into use. Vendor certificates for preweighed filters must be kept on file. For pre-weighed filters, the date put into use could be documented on the certificate supplied by the manufacturer. Exclude large floating particles or submerged agglomerates of nonhomogeneous materials from the sample if it is determined that their inclusion is not representative. ecause excessive residue on the filter may form a water entrapping crust, limit the sample size to that yielding no more than 200 mg residue. For samples high in dissolved solids thoroughly wash the filter to ensure removal of dissolved material Note method frequency of 10% is greater than 5% required by the Rules. nalyze at least 10% of all samples in duplicate. Duplicate determinations should agree within 5% of their average weight. This is not a requirement lab is required to set acceptance criterion. If lab is using %RD for acceptance criterion check low concentration samples for compliance may need to use a separate low level acceptance criterion may be based upon calculated recoveries or a ± mg/ criterion. nytime quality control results indicate an analytical problem the problem must be resolved and any samples involved must be reanalyzed if the holding time has not expired. Dates: check standard must be analyzed quarterly. n ash-type residue standard can be used and weighed as a QC, or a commercially

6 48 What acceptance criterion is used? [15 NCC 2H.0805 (a) (7)] 49 Is the data qualified on the Discharge Monitoring Report (DMR) or client report if Quality Control (QC) requirements are not met? [NC WW/GW C olicy] Total uspended olids (uditors Guide) age 6 prepared QC sample may be used. Establish acceptance criteria for standards prepared in-house or use the manufacturer s limits for purchased standards. ll documented results (e.g., benchsheets, reports and DMRs) must indicate appropriate qualifications. Verify traceability of consumables (e.g., filters). Verify reporting limit used on final reports/dmr. Calculations: mg total suspended solids/= ( ) x 1000 sample volume, m Where: = weight of filter + dried residue, mg, and = weight of filter, mg. dditional Comments: Inspector: Date: