2. AUDIT OBSERVATIONS

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1 Drinking Water Audit Report Local Authority: Kerry County Council Date of Audit: 16/09/08 Plant Inspected: Dromin Water Treatment Plant Listowel File Reference: DW2008/554 Supply Code (1300PUB1204) Auditors: Mr. David Smith Mr. John Feehan Dr. Ioannis Dokas UCC Researcher Audit Criteria: The European Communities (Drinking Water)(No. 2) Regulations, EPA Drinking Water Regulations Guidance Booklet No. 1 Regulation 9 and 10. The recommendations specified in the Handbook on Implementation of the European Communities (Drinking Water) Regulations The recommendations specified in the EPA Report titled The Provisions and Quality of Drinking Water in Ireland. A Report for the Years MAIN FINDINGS i. Kerry County Council should ensure that the drinking water treatment sludge is removed off site regularly. This issue was already the subject of Direction issued by the Agency on 26 th June 2007 but has again being allowed to accumulate on site. The management of drinking water sludge at the plant remains unsatisfactory despite previous enforcement action by the EPA. ii. iii. iv. A risk assessment is required to be undertaken on the location of the abstraction point for this drinking water treatment plant and this assessment should evaluate whether it should be relocate further upstream. Trends in raw water quality should be analysed and used to determine the optimum treatment conditions for the water at the plant An assessment of the need to have on-line monitors (particularly for ammonia, dissolved oxygen, ph or nitrogen) on the raw surface water intake for this plant should be made and documented. Source protection measures should be put in place and implemented to mitigate the risk to the drinking water supply where possible. 1. INTRODUCTION Under the European Communities (Drinking Water)(No. 2) Regulations 2007 the Environmental Protection Agency is the supervisory authority in relation to the local authorities and their role in the provision of public water supplies. This audit was carried out to assess the performance of the local authority in providing clean and wholesome drinking water. Another factor in deciding to audit this plant was because the source of the supply was recently affected by a substantial landslide. The opening meeting commenced at 10:30am at the Dromin Water Treatment Plant followed by an inspection of the raw water intake at Scartleigh. The Dromin water treatment plant, which serves 1,800 people in the Listowel area was built in 1976 to produce 1million- Page 1 of 16

2 gallons of treated water per day. The plant was extended in the 1980 s to provide an additional 2million gallons of water. The scope and purpose of the audit were outlined at the opening meeting. The audit process consisted of interviews with staff, review of records and observations made during an inspection of the treatment plant. The audits observations and recommendations are listed in Sections 2-4 of this report. The following were in attendance during the audit at the Dromin Water Treatment Plant: Representing Local Authority: Mr. Brian Sweeney - Senior Engineer Mr. Colm Mangan - Senior Executive Engineer Mr. P.J. McAuliffe - Area Technician Mr. John McEniry - Area Engineer Mr. John Lavery - Plant Caretaker Representing the EPA: Mr. David Smith - Inspector Mr. John Feehan Inspector Dr. Ioannis Dokas University College Cork Researcher 2. AUDIT OBSERVATIONS The audit process is a random sample on a particular day of a facility's operation. Where an observation or recommendation against a particular issue has not been reported, this should not be construed to mean that this issue is fully addressed. a) Source Protection The source of raw water for the Dromin water treatment plant is the River Feale, which is located a distance of 3km from the plant at Scartleigh (See Photograph 1). This raw water source is approximately 1-2 km downstream from the EPA licensed Kerry Ingredients Ireland Ltd facility whose waste water treatment plant discharges into the River Feale. The riverbank on the opposite side of the intake showed signs of erosion and possible cattle access (See Photograph 2). Kerry County Council has carried out Cryptosporidium risk screening to determine the relative risk of contamination of the supply with Cryptosporidium. The risk score was determined as 129 which indicates that the supply is categorised as very high risk. Raw water monitoring is carried out by the Environment Section of Kerry County Council. However, there is no documented procedure for reporting results to the operator of the water treatment plant or to the Environmental Manager of the Kerry Ingredients facility. There are no on-line monitors (ammonia, dissolved oxygen, ph or nitrogen) on the raw surface water intake. There is a turbidity meter on the raw water at the plant and Kerry County Council advised that it was planned to connect this to a data logger when the proposed SCADA system is installed at the plant. Kerry County Council advised that the provision of the SCADA system is at the tendering stage and Kerry County Council expect to appoint a contractor by November Kerry County Council carries out maintenance at the intake pump station as required. There is no planned or scheduled maintenance for equipment at the pump station. Kerry County Council outlined that land slide on the 24 th August 2008 resulted in highly coloured and peat laden water supplied to the plant. The caretaker advised that the plant was capable of treating this water. Page 2 of 16

3 b) Coagulation, Flocculation and Clarification Alum is dosed to the rising main prior to the addition of coagulant aid in a baffled contact tank (See Photograph 3). The alum dosing is controlled using twice daily jar tests and this procedure is documented and was presented at the audit. The plant caretaker advised that jar tests are carried out more frequently during periods when the raw water quality is likely to vary. The caretaker advised that the ph of the water in the contact tank is measured and recorded twice a day using a calibrated ph meter and the ph can be corrected using soda ash when necessary. The flow from the alum contact tank is split between 2 No. hopper (original design) and 4 No. flat bottomed (extension) settlement tanks. Sludge settlement appeared good on the day of the audit (See Photograph 4). The caretaker advised that there was an alarm in place to alert him if the sludge blanket began to rise above a set level. The sludge bleed from the settlement tanks is automatic. c) Filtration Following clarification the water flows into 6 No. rapid gravity filters. The filters are backwashed individually every two days. The frequency of backwashing is increased during periods of poor raw water quality. The auditors witnessed a forced backwash cycle, which showed some unequal air scour (See Photograph 5) in filter bed No. 1. The backwash consists of a 5 minute air scour and a 15 minute backwash of wash water to waste. Kerry County Council advised that the sand and gravel on each filter was replaced in 2006 and that the air nozzles on each filter bed had been checked. Kerry County Council advised that the sand depth was at least 1m in each filter bed. The surface of the sand layer in filter bed No. 1 is shown in Photograph No. 6. It was observed that skimming of the sand filters was necessary. There is a turbidity meter (6 off) (See Photograph No. 7) on the treated water from each filter bed and these were reading in the range NTU s on the day of the audit. d) Chlorination and Disinfection The primary method of chlorination of the treated water is electro-chlorination, which Kerry County Council described as a reliable system and produces a stock of up to two days chlorine. There is also a backup chlorination system in place at this plant whereby chlorous can also be used directly as a disinfectant on this supply in the event of a failure of the electro-chlorination system. The chlorine dosing pumps are configured with a duty and assist flow proportional pumping arrangement (See Photograph 8). Pump No. 1 (duty) delivers up to 85% of the chlorine requirement while pump No. 2 (assist) delivers the remaining chlorine requirement and this is controlled from a chlorine monitor (Hach Cl 17)(See Photograph 9). The total chlorine in the treated water is also recorded on a chart recorder which is located in the entrance hall of the treatment plant (See Photograph 10). e) Exceedances of the Parametric Values One aluminium result failed to meet the required standard of 200μg/l for this supply during 2007 with a reported value of 251 μg/l. There were also two ph and two fluoride exceedances reported in Page 3 of 16

4 f) Chemical storage and bunds Flourosilicilic acid is stored in a bunded area within a dedicated plant room (See Photograph 11). It was noted that some pipe work was penetrating the base of the bund (See photograph 12). Approximately 40 empty drums of sodium hypochlorite were being stored in the chemical preparation plant room at the works (See Photograph No. 13). These drums need to removed by an authorised waste collector. The diesel storage bund at the intake pump house was examined on the day of the audit. The diesel tank is located inside a bunded area however the pipe to the generator passes through the bund wall near ground level (See Photograph No. 14). The bund also contained rainwater up to the level of the outlet valve from the storage tank (See Photograph No. 15). g) Monitoring and Sampling Programme Daily monitoring at the plant includes ph, colour, turbidity, total chlorine and free chlorine. On-line monitoring is carried out at the plant using a Lange SC 1000 data logger which records raw water ph, settled water ph, raw water temperature and raw water turbidity. Kerry County Council advised that it was planned to connect this to the proposed SCADA system when it is installed at the plant. On the day of the audit the caretaker presented a sample of raw water, which was taken during the landslide event on 24 th August 2008 (See photograph 16). Daily monitoring for chlorine, aluminium and fluoride is carried out using a Hach DR It was noted that this instrument was due for calibration on 10 th November Monitoring carried at the plant is verified on a regular basis by the Kerry County Council central laboratory. Split samples are taken from the plant by the central laboratory for analysis. h) Management of Drinking Water Treatment Sludge Sludge is drawn off the bottom of the clarifiers and fed to a sludge dewatering plant which presses the sludge to approximately 15% solids. The supernatant from the sludge processing is discharged to the River Feale. There was no evidence of sludge carryover to the river on the day of the audit. Residual sludge is stored in an unbunded open area to the rear of the treatment plant (See Photograph 17). Kerry County Council advised that they had no arrangement or plan for the regular movement of sludge off-site. The storage of sludge at this treatment plant was subject of Direction issued on 26 th June 2007 under Section 63(5) of the EPA Acts. The direction required the removal of stored water treatment sludge from the plant. This Direction was complied with by Kerry County Council and verified to the EPA on 28 th December Records showing the removal of this sludge to landfill were presented at the audit. Scrap metal was also being stored in the area adjacent to the sludge at the rear of the treatment plant (See Photograph 18). i) Distribution System Treated water is passed to a clearwater tank on-site and pumped to 4 No. on-site reservoirs. The clear water tank is within a plant room at the treatment plant. The roof of the tank also forms part of the plant room floor. There were a number of holes in the floor, which presents a risk of contamination of the clear water tank below (See Photograph 19 & 20). Kerry County Council advised that the reservoirs had been cleaned in March 2008 and a service report from the contractor was presented at the audit. The reservoir cleaning report detailed the sludge removal process for each of the reservoirs and included an assessment of the reservoir structures and recommendations for remedial work on service hatches, vents and access ladders. Page 4 of 16

5 3. AUDITORS COMMENTS The management of this treatment plant would benefit from an on-line raw water monitoring system at the intake to provide advance warning of any changes in the variability or raw water, particularly as the intake point is downstream of a large industrial discharge. Of particular concern is the location of the abstraction point for this drinking water treatment plant, down stream from a large dairy facility with a waste water discharge. Kerry County Council are require to undertake a risk assessment on this abstraction point and evaluate whether it should be relocated further upstream. The management of sludge at the plant is a concern and the storage of sludge in the open is not a sustainable option. Although the plant was able to treat the water during the landslide event in August it is the opinion of the auditors that this posed a risk of plant failure and the treatment of such highly coloured water should be avoided in the future. 4. AUDIT RECOMMENDATIONS In view of the observations noted during the audit Kerry County Council is recommended to carry out the following; 1. Source Protection: Raw water monitoring should be carried out routinely on all raw water sources and the monitoring should include E.coli monitoring. Following the completion of the Cryptosporidium risk screening assessment the local authority should identify and implement measures to reduce the risk at the plant. 2. Source Protection: The local authority should install continuous automatic monitors at the intake to alert plant operators of any changes in raw water quality. 3. Source Protection: The local authority should liaise with the River Basin District team responsible for implementing the Water Framework Directive and establish links with the EPA and the Environment Sections in relevant local authorities in the catchment to ensure that they are aware of the issues potentially impacting on the raw water abstraction point. The local authority should identify all potentially polluting discharges into the catchment of the water source and shall implement mitigation measures where appropriate to reduce the potential impact of these discharges. In particular Kerry County Council should actively communicate with the operators of the Kerry Ingredients plant which discharges upstream of the raw water intake. The local authority should develop a documented protocol for dealing with exceedances of the discharge limits from Kerry Ingredients and should develop this protocol in conjunction with the EPA and Kerry Ingredients Ltd. Kerry County Council should also request access to real time discharge monitoring results for the discharge to the River Feale from Kerry Ingredients. 4. Abstraction point: Kerry County Council are require to undertake a risk assessment on the abstraction point from the River Feale for this drinking water supply and evaluate whether it should be relocated further upstream. 5. Coagulation, Flocculation and Clarification: The local authority should regularly review the operation and condition of the sand filters and ensure that any of the abnormal operating conditions identified (as outlined on pages 43 to 45 of the EPA Water Treatment Manual on Filtration) are rectified. 6. Filtration: Turbidity monitors should be linked to a recording device and alarm in the event of a deviation from the acceptable operating range of the filters. 7. Filtration: The local authority should ensure that a logbook is kept ( the filter logbook ) for each filter containing the following; a record of all maintenance work and inspections carried out on the filter; details of the media depth and the condition of the filter when it is drained down; where appropriate, details of the operation of the backwashing / air scouring systems and underdrains; Page 5 of 16

6 details of any changes or required changes to filters, the backwashing /air scoring systems or underdrains, and 8. Chlorination and Disinfection: The local authority should review the method of disinfection to ensure that the formation of disinfection by products is minimised and does not exceed the following levels: Chlorate 0.7 mg/l Chlorite 0.7 mg/l 9. Distribution System: The local authority should ensure that the remedial actions highlighted in the reservoir cleaning report are carried out. 10. Chemical Storage and Bunds: The local authority should review chemical storage arrangements at the treatment plant and pump house. Chemicals/fuels must be stored in bunded areas capable of containing at least 110% of the volume of chemicals stored therein. Fill points for storage tanks inside the bunds should be located within the bunded area. Refer to EPA guidance document - IPC Guidance Note on Storage and Transfer of Materials for Scheduled Activities 11. Chemical Storage and Bunds: The local authority should ensure that inspection covers on treated water tanks and pipelines within buildings that contain equipment that could leak (for example oils from pumps and compressors) are sealed or raised to prevent direct access of any leaks into the water supply. All holes in the treated water tank roof should be sealed. 12. Sludge Management: The local authority should review current methods of handling and disposal of water treatment sludge to ensure that the practice is not in contravention of the Waste Management Act, This should be carried out as a priority given that sludge management at the plant was the subject of previous enforcement actions by the Agency. 13. Hygiene and Housekeeping: The local authority should undertake a review of house keeping and waste storage at the plant and take measures to ensure that the plant is kept well maintained, clean and tidy. All scrap metals and other waste (including empty drums) should be removed to a suitably authorised facility. 14. Management and Control: A documented system of regular internal auditing and supervision of the treatment plant by senior experienced personnel in the local authority should be implemented and copies of quality assurance checks and audits records kept on site for inspection by the Agency. 4. Follow-Up Actions required by the local authority: During the audit the local authority representatives were advised of the audit findings and that action must be taken as a priority by the local authority to address the issues raised. The local authority is recommended to put such measures in place as are necessary to implement the recommendations listed in this report. The actions taken by the local authority to address the recommendations will be verified by the Agency during any future audits. Report prepared by: Date: David Smith Inspector Reviewed by: Date: Brendan Wall Senior Inspector Page 6 of 16

7 Photograph 1: Raw water intake on River Feale. Photograph 2: River bank opposite raw water intake on River Feale. Page 7 of 16

8 Photograph 3: Polyelectrolyte dosing. Photograph 4: Sludge settlement and clarification. Page 8 of 16

9 Photograph 5: Air scour on filter bed No. 1. Photograph 6: Surface of filter bed No. 1 following the backwash cycle. Page 9 of 16

10 Photograph No. 7: Turbidity meter on filtered water Photograph No. 8: Chlorine dosing pumps. Page 10 of 16

11 Photograph No. 9: Hach CL17 Chlorine monitor. Photograph No. 10: Chlorine chart recorder. Page 11 of 16

12 Photograph 11: Fluoride storage. Photograph 12: Pipe work passing through fluoride storage bund. Page 12 of 16

13 Photograph 13: Used sodium hypochlorite drum storage in an unbunded area. Photograph 14: Pipe passing through bund wall. Page 13 of 16

14 Photograph 15: Submerged outlet valve of diesel tank. Photograph 16: Samples of raw water received at the plant following a landslide. Page 14 of 16

15 Photograph 17: Residual sludge storage to the rear of the treatment plant. Photograph 18: Scrap metal storage to the rear of the treatment plant. Page 15 of 16

16 Photograph 19: Potential contamination pathways into the clearwater storage tank. Photograph 20: Potential contamination pathways into the clearwater storage tank. Page 16 of 16