DISTRIBUTION LIST To be filled out by Document Author or person requesting document deletion

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4 DISTRIBUTION LIST To be filled out by Document Author or person requesting document deletion: Once approved, the new or revised document or the notice of deleted document(s) should be distributed to all persons identified below: ( ) All RP staff members ( X ) All holders of the following manual(s): SLAC Radioanalysis Laboratory Procedures ( ) The following individuals: November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 4

5 TABLE OF REVISIONS REVISION DATE SECTION(S) REASON FOR REVISION # 001 March 11, 2003 B, C, D, K, Prevent Generation of Mixed Waste By Changing Sample to Cocktail Ratio 002 July 16, 2003 B, C. D, K, Increase efficiency and lower count times 003 November 17, 2006 All Rewrite of procedure to incorporate LSC Source Check procedure. LSC Counting checklist added to appendix. November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 5

6 TABLE OF CONTENTS LSC Procedure 1 PURPOSE REFERENCES RESPONSIBILITIES Rad Lab Operator REP Manager PREREQUISITES PROCEDURES Perform a Source Check Prepare the Sample Count the Sample Determine the Results Dispose of the sample RECORDS ATTACHMENTS/FORMS Attachment 1: Routine Liquid Scintillation Counting Checklist November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 6

7 1 PURPOSE LSC Procedure The purpose of this procedure is to provide general guidance for operating the Liquid Scintillation Counter (LSC). The LSC Sample Counting procedure applies to anyone characterizing liquid samples in the Radioanalysis Laboratory (Rad Lab). This procedure outlines the steps for counting LSC samples. A Routine Scintillation Counting Checklist (Attachment 1) is attached to provide detailed instructions for routine LSC counting using current Rad Lab equipment. Refer to instrument specific operating manuals when performing LSC analysis with non-rad Lab equipment. 2 REFERENCES 2.1 Packard Tri-Carb 1900TR Operational Manual 2.2 SLAC Rad Lab Manual, General Sample Analysis Procedure 3 RESPONSIBILITIES 3.1 Rad Lab Operator The Rad Lab Operator assigned to perform activities described in this chapter is responsible for: ensuring that prerequisites are met as required, maintenance of the laboratory equipment and performing daily quality control checks, reporting any problems or unexpected events to the Radiological Environmental Protection (REP) Manager, routine sample analysis counting, providing the data to the REP Manager for analysis and approval, and Performing other duties assigned by the REP Manager. 3.2 REP Manager The REP Manager is responsible for: ensuring that the activities in this chapter are conducted in accordance with this written procedure, November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 7

8 LSC Procedure assigning the tasks in this procedure to a qualified operator, and providing final approval or disapproval of all data and submittals. 4 PREREQUISITES 4.1 Must be familiar with Windows operating menus, Microsoft Access and Notepad. 4.2 Must be familiar with Rad Lab general sample analysis procedures 4.3 Must have a basic understanding of Liquid Scintillation Counting theory 4.4 Must be familiar with general laboratory equipment and methods (pipettes, scales, distillation etc.) 5 PROCEDURES 5.1 Perform a Source Check As part of the instrument quality control process, the Self Normalization and Calibration (SNC) protocol should be run daily when the LSC system is in use. The SNC protocol is performed by counting the H-3, C-14, and background standards in the SNC labeled tray. A generated report displays H-3 and C-14 efficiencies upon completion of the SNC protocol. These values are reviewed to determine if the LSC is operating within specifications. Acceptable values are listed in the instrument s operational manual. If the efficiencies are not within specifications, the LSC should be repaired as needed. Otherwise sample counting can proceed. 5.2 Prepare the Sample Sample preparation requires the use of appropriate PPE. At a minimum latex gloves and eye protection should be used. A pipette, tips, vials, and liquid scintillation cocktail fluid are necessary supplies in order to prepare the sample. General sample preparation is performed by marking a liquid scintillation vial with the sample number, pipetting a volume of the sample into the vial, and adding scintillation cocktail to help facilitate the detection of radiation. After capping the vial the samples are placed in the appropriate protocol tray and are ready for counting. There are some samples that require special preparation prior to counting. Swipes, for instance, require additional sitting time once cocktail is added in November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 8

9 LSC Procedure order to allow for the swipe to dissolve. Refer to the checklist (Attachment 1) for more specific instructions on how to handle these special cases. 5.3 Count the Sample Determine the counting protocol for the sample. For instance, LCW samples are counted under protocol 1 for 30 minutes and environmental/well samples count under protocol 13 for 250 minutes. Refer to the checklist (Attachment 1) to determine the appropriate counting protocol. Samples are to be counted in sets. Each set must include at least one background sample. Each set must also include quality control samples. As a minimum two identical spiked blanks must be included. The spiked blanks are used to calculate quality control statistics as well as confirm quality control during batch counting. 5.4 Determine the Results Upon completion of counting a report is generated by the LSC. The results should be reviewed for any unusual trends. Examples are high luminosity (LUM >30) values and large DPM deviations between the spiked blanks. A high CPMC (2X background) may indicate the need for Gamma spectroscopy. In some cases there may be spillover into the tritium channel from other nuclides. Distillation may be required to determine actual tritium content. Make sure that the batch background results are in agreement with the background counts for the source check. Contact the REP or FO manager if any unusual trends appear. The following formula is used to calculate the tritium concentration in pci/l: (Sample DPM - BKG DPM)*X = pci/l Conversion factor X=(1/SV)*(1000ml/L)*(1pCi/2.22DPM) where: SV is the volume of sample in the vial. So for SV= 5.0 ml: X= (1/5.0 ml) * (1000ml/l)*(1pCi/2.22DPM) X= 91 pci/l-dpm The minimum detectable activity depends on the counting protocol used (see Attachment 1). If the sample results are less than or equal to the applicable MDA, the sample activity is reported as No Detectable Activity (NDA). If the sample results exceed the applicable MDA, report the sample activity in pci/l. November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 9

10 LSC Procedure 5.5 Dispose of the sample 6 RECORDS Upon completion of analysis LSC vials (including contents) are discarded in the appropriate waste container. There is a satellite accumulation area where the waste containers are stored. The chemical and radiological characteristics of the samples determine their waste streams. Refer to the checklist (see Attachment 1) to determine the correct waste receptacle for each LSC vial. The sample, container, and release documentation are returned to the customer. A copy of the documentation is filed in the Rad Lab archive. 6.1 All analysis results generated from this procedure must be entered into the REP Rad Lab database on the network drive to ensure data access, security control, and backup. 6.2 All hardcopies of the Analysis reports generated from this procedure should also be provided and stored in the Rad Lab archives. 7 ATTACHMENTS/FORMS 7.1 Attachment 1: Routine Liquid Scintillation Counting Checklist November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 10

11 LSC Procedure 7.1 Attachment 1: Routine Liquid Scintillation Counting Checklist Done? Step No. Item [ ] 1. Complete Steps 1 7 of Sample Analysis Checklist (SAC). [ ] 2. If the monitor for LSC is not illuminated, pull out the keyboard & depress space key. [ ] 3. Confirm that display shows STATUS PAGE in upper left corner. If not, don t proceed, notify the REP or FO mgr. [ ] 4. If a source check is not required (see step 7 of SAC), proceed to Step 9. Perform Source Check [ ] 5. Source check: Confirm that the SNC tray is in the LSC that the standard H-3, C-14, & background vials are in that tray. Handle the vials by their caps; fingerprints on the vials may produce errors during Self normalization and Calibration (SNC) [ ] 6. Move the flag on the SNC tray to the left. [ ] 7. If STATUS PAGE shows the LSC mode as IDLE at the top center of screen, press [F2] on keyboard to start the count. [ ] 8. When the count of the standards is complete, review the print-out. Consult with the REP or FO mgr if: C14 Eff < 94% or H3 Eff <58% or Bkg ( kev) > 25 cpm or Bkg (0-156 kev) > 50 cpm [if this last background count rate is high, check neutron source use in Cal Lab). Prepare the Sample [ ] 9. Label a vial cap with the Sample ID printed on the sample bottle label. Put on gloves. [ ] 10. Verify that the Ultima Gold scintillation fluid dispenser is set for 5 ml [ ] 11. If preparing a sample with a swipe, skip to Step 15. Otherwise proceed with Step 12. November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 11

12 Done? Step No. Item LSC Procedure [ ] 12. Add 15 ml scintillation fluid (three pipettes-full) to an empty vial. [ ] 13. Place new tip (10 ml) on pipette, verify pipette is set for 5 ml. [ ] 14. Carefully pipette 5 ml of liquid from the sample bottle to the vial (be careful to avoid drips). Immediately discard the pipette tip using the Rad lab waste receptacle. Cap the sample bottle and the vial. Skip to Step 17. [ ] 15. To prepare a LSC vial for a swipe, put the swipe in the vial. [ ] 16. Pipette 5 ml of tap water into the vial. Add 15 ml scintillation fluid to the vial with the swipe. [ ] 17. Cap the vial with the cap (labeled with sample ID) & shake it. Allow the vial to sit long enough to dissolve (~ 30 min.). [ ] 18. Discard gloves using bin labeled for pipettes & gloves. Count the Sample [ ] 19. Determine the LSC protocol required for the sample. All samples collected by EP (e.g. water collected for storm water analysis) and ALL samples from groundwater wells (regardless of who collected) must be counted using Protocol 13; other samples may use Protocol 1 or 13, depending on the sample and the location. [ ] 20. Place the appropriate background standard in the corresponding protocol tray (1 or 13). In the adjacent slots, place the BKG standard, then the standard STD1, next the sample(s), & finally standard STD2. If any of the vials are for swipes, include the vial with the background swipe in the tray. Likewise, if you have a vial with an oil, well, or MCC sample, include the appropriate background standard. Standards STD1 & STD2 are de-ionized water with nearly identical H-3 concentrations. [ ] 21. Push the protocol flag to the left & place the tray in the LSC. [ ] 22. If STATUS PAGE shows the LSC mode as IDLE at the top center, press [F2] on keyboard to start the count. Determine the Results November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 12

13 Done? Step No. Item LSC Procedure [ ] 23. When the count is complete, label the results on the print-out, clearly writing the background, standard, and sample ID next to the applicable count for each. 24. Review the print-out. If the value in CPMC is about same (< 2X Bkg) for the sample as for the background vial, skip to Step 26. Otherwise, if CPMC for sample is higher (~double or more), then alert the REP program manager to determine if GS is needed. [ ] 25. On LSC print-out, consult with the REP or FO mgr if: 1) Within any one column (CPMA or A:2S% or CPMB or CPMC or SIS or tsie or LUM of DPM1) the values recorded for STD1 & STD2 are not similar, or 2) For any standard or sample, CPMB > CPMA or CPMA >> CPMB, or 3) For any sample the value in SIS is very different (e.g. double or half) from that for the BKG LCW standard. 4) For any sample, the value for tsie isn t w/ in a few hundred of the value for the standards, or 5) For any sample, the value for LUM is high (e.g. 40 or 50), or 6) The column FLAG has an indicator. [ ] 26. If previous step OK, determine the amount of H-3. To calculate the concentration, C, in a liquid, use the following formula: C(pCi/L) = (Sample DPM Bkg DPM) x 91 For a swipe no calculation is needed. If the sample DPM is > 1000, notify the FO manager to determine if additional swipes are needed. If sample DPM <1000, then the swipe is NDA. [ ] 27. Record the results, identified by sample ID, on the print out. [ ] 28. If the results are unexpected (e.g. H-3 detected in a location or well where H-3 has not been detected in past or no H-3 in a location or well that normally has H-3), alert the REP or FO mgr immediately. November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 13

14 Done? Step No. Item LSC Procedure [ ] 29. Mark any counted vial that was found to contain radioactivity (at or above the detection limit) with a radioactive materials label. Dispose of sample and Complete Sample Analysis Checklist [ ] 30. Discard the counted LSC vial into one of the three satellite accumulation bins: All rad vials (regardless of origin) Non-rad vials containing water from a SLAC well All non-rad vials, EXCEPT ones that contain water from a SLAC well. [ ] 31. Complete Steps 9 end of Sample Analysis Checklist (information on labeling & storage or return of sample is included in that procedure). November 27, 2006 SLAC-I-760-2A39C-008-R-003 Page 14