LEGIONELLA TESTING IN POWER STATION WATERS. KKS: CA0G, CB0G and CC0G

Transcription

1 CS ENERGY PROCEDURE FOR LEGIONELLA TESTING IN POWER STATION WATERS CWP-CH-3003 KKS: CA0G, CB0G and CC0G Responsible Officer: [Insert Title] Approved: [Insert Title] DOCUMENT HISTORY Date Key Changes Author Approver Page 1

2 CONTENTS DOCUMENT HISTORY PURPOSE SCOPE RESPONSIBILITIES AND ACCOUNTABILITIES Manageent Eployees Contractors / Consultants LIMITATIONS SAMPLING REQUIRMENTS Container... 4 BIOTECH LABORATORIES Miniu Saple Volue Requireents Collection and Preservation SAFETY PRECAUTIONS APARATUS REAGENTS... 5 NOT APPLICABLE PROCEDURE Sapling Procedure Saple Dispatch Procedure CALCULATION... 6 NOT APPLICABLE PRECISION... 6 NOT APPLICABLE ACCURACY REPORTING DEFINITIONS REFERENCES ATTACHMENT / APPENDIX inal Saple Points/ Frequency Legionella Control Strategy Flow Chart Page 2

3 1 PURPOSE The inhalation of Legionella bacteria in high counts can cause serious illness and the possibility of death and requires frequent onitoring. 2 SCOPE This procedure details the ethod used for the collection of water saples for legionella exaination 3 RESPONSIBILITIES AND ACCOUNTABILITIES 3.1 Manageent Manageent are responsible for ensuring that: All staff and contractors following the procedures and observe the safety precautions 3.2 Eployees Eployees are responsible for ensuring that: They follow the procedure and observe the safety precautions 3.3 Contractors / Consultants Contractors / Consultants are responsible for ensuring that: They follow the procedure and observe the safety precautions 4 LIMITATIONS 4. Liitations Detection liit for exaination are as follows: Plate Counts: >2000 to < CFU/L Legionella pneuophilia serogroup 1-14: <10 CFU/L Legionella species not pneuophilia: <10 CFU/L Page 3

4 5 SAMPLING REQUIRMENTS 5.1 Container Saples are collected in sterile, disposable, plastic saple jars. These containers are currently preprepared and obtained fro: Biotech Laboratories Level 2 Adinistration Building Greenslopes Private Hospital Newdegate Street Greenslopes QLD 4012 Phone: Fax: Each saple container used shall be labelled with the following: Saple Description CS Energy Callide B Power Station Date and Tie of Sapling The tests required to be carried out 5.2 Miniu Saple Volue Requireents Plate Count: Legionella: 10L 120 L 5.3 Collection and Preservation When chlorinated waters are sapled then sufficient pre-sterilised sodiu thiosulfate (100 g.l -1 ) solution shall be present in the saple container. This neutralises the residual chlorine in the saple. Sterilised containers ust not be opened prior to saple collection. Any containers found to have loose lids or in any other way being suspected of containation ust be discarded. Saples ust be collected so that soe air space is left in the container. To reduce the risk of containation, where appropriate gloves should be worn. Page 4

5 6.0 SAFETY PRECAUTIONS Where there is a possibility of inhalation of cooling tower spray, then personal protective equipent in the for of a ist-approved respirator ust be used by the saple collector. Under such conditions where a ist-approved respirator ust be worn it is preferable that the sapler does not have a beard as this significantly reduces the effectiveness of the respirator. Respirator cartridges should be discarded after each usage. 7. APARATUS Saple Container Gloves Watch 8. REAGENTS t Applicable 9.0 PROCEDURE 9.1 Sapling Procedure When sapling fro a saple point allow the water to run freely for a iniu of 1 inute prior to filling the saple container. Reove the saple container cap only when the saple is ready to be taken. Keep the cap turned downwards to prevent containation. do not set down the cap (hand-hold cap) do not touch the inside surfaces of the container, container lip or cap do not flush the container or lid prior to sapling For saples of exposed bulk water, hold the saple container fro its base and plunge it approxiately 50 below the surface. Turn the container so that the neck points slightly upwards. Create an artificial current by pushing the container horizontally forwards and away fro the hand. In circustances where the bulk water to be sapled has been chlorinated (i.e. sodiu thiosulfate is required), hold the saple container fro its base so that the neck points slightly upwards. Obtain a surface saple by pushing the container horizontally forwards and away fro the hand Saple containers shall be filled so that soe air space still reains. The cap should be replaced firly and the saple container inverted and tested for leaks The saple container should be dried and a label attached. The labelling ink should not be watersoluble. Page 5

6 9.1.5 After collection saples should be stored in the refrigerator until they are ready to be dispatched. 9.2 Saple Dispatch Procedure Saples should be dispatched to the testing laboratory as rapidly as possible. Biotech Laboratories Level 2 Adinistration Building Greenslopes Private Hospital Newdegate Street Greenslopes QLD The saple should be received by the testing laboratory at a axiu of 24 hours after sapling and preferably less Saples should be placed in an insulated container (eg. "Esky") with sufficient ice bricks to keep the saples cool. It is iportant that the saple is NOT frozen Containers shall be arked Urgent to ensure delivery within 24 hours CALCULATION t Applicable 11. PRECISION t Applicable 12.0 ACCURACY t Applicable 13.0 REPORTING All saples when collected shall be entered into WINLIMS. When received results should also be recorded into WINLIMS. Cooling water results shall be reviewed with respect to the cheical dosing regie at the tie. 14. DEFINITIONS Ter Definition Page 6

7 15. REFERENCES Reference Reference Title Author ASNZS Standards Standards Australia International Ltd. 16. ATTACHMENT / APPENDIX 16.1 inal Saple Points/ Frequency Syste Sapled B1 Cooling Water, After Condenser B2 Cooling Water, After Condenser C3 Cooling Water, After Condenser C4 Cooling Water, After Condenser SCC Cooling Tower Raw Water Ash Da B Callide B Ashing Water Drains Reclai Da Reclai Coal Plant Sprinkler Syste Adin Building Sprinkler Syste Annex Supply, B Test Valve Callide B Site Fire Fighting Syste Callide A Fire Fighting Syste Frequency w w w w w Page 7

8 16.2 Legionella Control Strategy Chlorine Plant Strategy Test result Required control strategy Plant perforance to be checked daily by cheical plant operators to confir that the plant has injected the required ties in the past 24 hours to each tower Plant dosed according to schedule (1) Maintain progra. Loss of chlorination fro any sort of chorine plant alfunction. Action Level 1-loss of one chlorination cycle to a tower. Plant to be repaired within 24 hours. People on site to be infored of Action level 1 status. Need to consider chlorination effectiveness prior to the loss of chlorination in deterining response activity. Action Level 2-Chlorination not restored within 24 hours. People on site advised to wear P2 asks in vicinity* of the effected tower[s] until double chlorination copleted. Once chlorine plant restored, double chlorination for next 24 hours followed iediately by sapling for Legionella testing. (2) Chlorine Dosing Control Strategy Test result (g/l post chlorination) Required control strategy (1) Maintain tri-weekly onitoring. Maintain chlorination regie Detected as <0.5 Action Level 1- Chlorine residual less than 0.5pp. Site advised by Station Cheist of Action level 1 status. Plant adjustents ade and each successive cycle tested until 0.5pp achieved. Action Level 2-0.5pp chlorine residual not achieved for 3 successive injections. Site advised by Station Cheist to wear P2 asks in the vicinity of the effected tower/towers until double chlorination copleted. Double chlorination for next 24 hours after residual achieved. (3) Undertake icrobial test within a day of double chlorination. Page 8

9 Heterotrophic Organis Control Strategy Test result (cfu/l) Required control strategy 1. < (Maintain onthly onitoring Maintain water treatent progra 2. > < Investigate proble Review chlorine plant, unit plant and all other test data fro the date of the previous sapling to the date of the sapling of the high result. If all other data is according to the anageent plan, then the high result is interpreted as a rogue saple, a precautionary double duration chlorination injection will be undertaken. 3. > Investigate proble Action Level 1-If all the plant and test data is not all according to the anageent plan. Double chlorination for 24 hours and subsequently sapled for Total Plate Count and Legionella testing. te-if there is a non-conforance in the plant/test data, then corrective action would have already been taken, along with another saple for Legionella testing. See ites 1/. and 2/. above. Therefore this Total Plate Count result would no longer be relevant. Therefore consider this result only if corrective action had not been already been taken. Action level 2-Subsequent Total Plate Count test also to cfu/l. Site advised by Station Cheist to wear P2 asks in vicinity* of effected tower[s] until Total Plate Count results show less than cfu/l. Double chlorination for 48 hours and subsequent sapling for Total Plate Count and Legionella. Review water treatent progra Take necessary reedial action including iediate on-line disinfection in accordance with Appendix B and undertake control strategy Retest water within 3 to 7 days of plant operation (a) If test result is < cfu/l repeat control strategy (1) (b) If test result is > cfu/l but < cfu/l repeat control strategy (4) (c) If test result is > cfu/l investigate proble and review water treatent progra, carry out iediate on-line decontaination in accordance with Paragraph C2 of Appendix C and repeat control strategy (5) Page 9

10 Legionella Control Strategy 1 Test result (cfu/l) Required control strategy t detected (<10) Maintain Weekly onitoring. Maintain water treatent progra. 2. Detected as <1000 Legionella Results 100 to 1000cfu/l.[After chlorination] Review chlorine plant, unit plant and all other test data fro the date of the previous sapling to the date of the sapling of the high result. If all other data is according to the anageent plan, then the high result is interpreted as a rogue saple, a precautionary double duration chlorination injection is carried out and a saple for Legionella testing is taken subsequently. Action Level 1- If all the plant and test data is not all according to the anageent plan. Double chlorination for 24 hours and subsequently sapled for Legionella testing. te-if there is a non-conforance in the plant/test data, then corrective action would have already been taken, along with another saple for Legionella testing. See ites 1/. and 2/. above. Therefore this Legionella result would no longer be relevant. Therefore consider this result only if corrective action had not been already been taken. 3. Action level 2- subsequent Legionella test also 100 to 1000cfu/l. Site advised by Station Cheist to wear P2 asks in vicinity* of effected tower[s] until Legionella results show less than 10cfu/l. Double chlorination for 48 hours and subsequent sapling for Legionella. Retest water within 3 to 7 days of plant operation a) If not detected, continue to retest water every 3 to 7 days until two consecutive saples return readings of not detected and repeat control strategy (1) (b) If detected at <100 cfu/l repeat control strategy (2) c) If detected at ³100 cfu/l investigate proble and review water treatent progra, iediately carry out on-line decontaination in accordance with Paragraph C2 of Appendix C and repeat control strategy (3) 4. Detected as >1000 (d) If detected at ³1000 cfu/l undertake control strategy (4) (4 Legionella Results greater than 1000cfu/l.[After chlorination] Action Level 2- Site advised by Station Cheist to wear P2 asks within vicinity* of the effected tower[s] until Legionella results show less than 10 cfu/l. All plant and test data reviewed to identify fault. Double chlorination for 48 hours and subsequently sapled for Legionella testing. te-as for 3/. Action Level 1, corrective action would have already been taken, and so this result would no longer be relevant. Therefore consider this result only if corrective action had not already been taken. Page 10

11 Vicinity Areas- [a] B tower proble. Southern workshop[except within the workshop if all doors/louvres kept closed on the eastern side and roof vents closed], Cheical plant along Turbot St., any equipent on/around the tower, e.g. screens, float valves etc. [b] C3 tower proble. Southern Workshop [except within the workshop if all doors/louvres kept closed on the western side and roof vents closed], CPP polisher regen and BD Water treatent plant, any equipent on/around C3 tower. 5. [c] C4 tower proble. BD Water treatent plant. Any equipent on/around C4 tower. Retest water within 2 days of precautionary double chlorination. (a) If not detected, continue to retest water every 2 days until two consecutive saples return readings of not detected and repeat control strategy (1) (b) If detected at <100 cfu/l, repeat control strategy (2) (c) If detected at ³100 <1000 cfu/l investigate proble and review water treatent progra, iediately carry out on-line decontaination in accordance with Paragraph C2 of Appendix C and repeat control strategy (5) (d) If detected at >1000 cfu/l investigate proble and review water treatent progra, iediately carry out syste decontaination in accordance with Paragraph C3 of Appendix C and repeat control strategy (5) Page 11

12 16.3 Flow Chart Adjust Chlorine Dosing Paraeters Saple for Chlorine residuals Saple for total plate count Saple for legionella Routine Monitoring regie Receipt data Receipt data Receipt data Is Cl2<0.5 cfu>2000 cfu>10 Is Cl2 >1.0 Page 12

13 Presence of HETEROTROPHIC Microorganiss < cfu/ L Saple taken and analysed. Investigate, Saple taken and < cfu/ < cfu/ review, disinfect. analysed. L L < cfu/ L Investigate, review, disinfect. Investigate, review, disinfect. < cfu/ L < cfu/ L Legionella Monitoring Process Control >= 10 cfu/l detected <1000 cfu/l Investigate, review, decontainate. Saple taken and analysed. Saple taken and analysed. Investigate, review, decontainate. Saple taken Analysed after7 days) Saple taken Analysed after7 days) >= 10 cfu/l detected <100 cfu/l <1000 cfu/l >= 10 cfu/l detected <100 cfu/l <1000 cfu/l Investigate, review, decontainate. Saple taken Analysed after7 days) Investigate, review, decontainate. Saple taken Analysed after7 days) >= 10 cfu/l detected >= 10 cfu/l detected Page 13