ANNUAL REPORT 2016 to 2017

Transcription

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2 Wastewater Discharge Consent CD130214W Annual Report 1 July 2016 to 30 June 2017 Prepared by: R McWilliams BSc (Chemistry) Wastewater Treatment Manager Hastings District Council Independently Reviewed By: David Cameron Senior Environmental Scientist (BSc Zoology, Hons) Stantec - Engineering Services Company

3 Executive Summary The purpose of this report is to assess compliance with Consent CD130214W. The consent is for the discharge of the Final Treated Wastewater (Domestic and Non Separable Industry (DNSI) treated wastewater and the Separable Industrial Wastewater) discharged through a long ocean outfall (2.75km) into Hawke Bay. The compliance with the consent is very high. The DNSI treatment is well below the annual average loading rate required by the consent. There has been an increasing load for the treated COB and Total Oil and Grease which indicates the treatment performance is slightly down. The BOD removal remains about the same so the plant continues to operate and provide the cultural treatment of the DNSI before discharge through the 2.75 Km long ocean outfall. The Final Combined Discharge complies with all the contaminant levels required by the consent. There are some increasing and decreasing trends and the discharge complies with the ANZECC 2000 guidelines when allowance is made for the 100:1 dilution at the diffuser. The Time Trends analysis of the TEC and NOEC show no evidence to suggest either an increasing or decreasing level of toxicity The receiving water shows no statistical differences between any site for any parameter indicating the receiving water is similar for each site including those sites close to the outfall and the river mouths. The box and whisker diagrams show some localised changes that could be attributable to the outfall or the rivers but they are not statistically significant The sediment analyses show some differences between sites but there is no commonality between different parameters. The box and whisker diagrams show an elevation of some levels to the south of the outfall. There are both increasing and decreasing trends for some of the parameters. Overall the sediments comply the ANZECC 200 sediment quality guidelines. The report concludes that overall the current treatment and discharge through the long offshore ocean outfall provides for an environmentally and culturally acceptable, sustainable and economic solution for wastewater from the Hastings District Council Record Number WAT i

4 CONTENTS Executive Summary... i Introduction General Abbreviations... 2 Data Analysis and Interpretation Analytical Results Trend Analysis for Wastewaters Analysis of Sediments and Water Quality Monitoring Trend Analysis for Toxicity Testing... 3 Compliance and Adverse Environmental Effects (24c) Compliance with the Consent Adverse Environmental Effects Compliance Assessment (24c)... 4 Domestic and Non-separable Industry (DNSI) Monitoring Results Summary of Monitoring Undertaken (24a) Biological Trickling Filter Treatment (24b & 13) BTF Treatment Performance (24b) Trend Analysis DNSI and BTF Treated Wastewater (24d) Assessment of Effects of the BTF Treated Wastewater Final Combined Wastewater (FCW) Quality & Quantity Monitoring Results Summary of Monitoring Undertaken (24a) Final Combined Wastewater Results (24c & 13c) Assessment of Compliance with Trigger Values (24c & 24d) Trend Analysis (24d & 24g) Assessment of Effects of the Final Combined Discharge Combined Wastewater Toxicity Assessment Summary of Monitoring Undertaken (24a) Analysis of Results (24g) Toxicity Trend Evaluation Receiving Water Quality Monitoring Results Summary of Monitoring Undertaken (24a) Analysis of Results (24c) Assessment of Differences between Sites Assessment of Effects (24c) Marine Sediment Quality Monitoring Results Summary of Monitoring Undertaken (24a) Analyses of results (24c) ii

5 8.3 Assessment of Difference between sites Assessment of trends (24c) Assessment of Effects (24c) Treatment Plant Performance and Improvements Treatment Plant Performance (24c 24e) Non Compliance (24c) Operational Matters (24c) BTF Distributor Septage Treatment DNSI Screening Sewer Relining Outfall Repairs Industrial Screening Odour Odour at the Plant Boundary (Odour Management Plan) Odour issues with the Discharge (7d) Improvements (24f) Recommendations for Future Monitoring (24h) Proposed changes to Consent Conditions (24i) Condition Condition Condition 24 (d) Condition Comment on Open Day (24j) Report Conclusions Appendix A - Tabulated data results (24k) Appendix B - Toxicity Decision Tree LIST OF TABLES Table 1 DNSI Wastewater Table 2 BTF Treated Wastewater Results Table 3 BTF Plant performance (% Reduction) Table 4 DNSI and Treated BTF Wastewater Trends Table 5 Final Combined Wastewater Results Table 6 Final Combined Wastewater Annual Results Excluding Organics (additional analyses) Table 7 Final Combined Wastewater Annual Results Quarter 1&4 Organics Table 8 Compliance with Trigger Values Table 9 Final Combined Wastewater Trends Table 10 Toxicity Results iii

6 Table 11 Average levels for Table 12 Sediments - Metals Analysis 2016/17 Average (Maximum in parenthesis) Table 13 Sediments - Volatile Solids & Grain size - Average (maximum in parenthesis) Table 14 Tin Difference between sites Table 15 Arsenic - Difference between sites Table 16 Cadmium - Difference between sites Table 17 Chromium - Difference between sites Table 18 Copper - Difference between sites Table 19 Lead - Difference between sites Table 20 Mercury - Difference between sites Table 21 Nickel - Difference between sites Table 22 Zinc - Difference between sites Table 23 Volatile Solids - Difference between sites Table 24 Sediments - 750m North - Trends Table 25- Trends Sediments - 500m North Trends Table 26 Sediments - 250m North Trends Table 27 Sediments - 250m South Trends Table 28 Sediments - 500m South Trends Table 29 Final Combined Wastewater Daily Flow Measurements Table 30 Final Combined Wastewater Peak Flow Rate Measurements Table 31 DNSI and Treated Wastewater from BTF Results Table 32 Quarterly Analysis Final Combined Wastewater Results Table 33 Final Combined Wastewater Organonitrogen and Organophosphorous Pesticides Results Table 34 Final Combined Wastewater Volatile Organic Compounds Results Table 35 Final Combined Wastewater Semi Volatile Organic Compounds Results Table 36 Final Combined Wastewater Polychlorinated Byphenols Results Table 37 Annual Final Combined Wastewater Results (Does not include Quarterly Analyses) Table 38 Sediments Total Recoverable Metal Results Table 39 Receiving Water Monitoring Results Table 40 Receiving Water Microbiological Monitoring Results Table 41 Receiving Water Drogue Monitoring Results Table 42 Final Combined Wastewater Toxicity Monitoring Results Table 43 Odour Complaints Received LIST OF FIGURES Figure 1 HDC Wastewater Treatment - Flow paths... 1 Figure 2 Water Quality Sampling Sites Figure 3 Receiving Water ph Figure 4 Receiving Water Temperature iv

7 Figure 5 Receiving Water Dissolved Oxygen (%) Figure 6 Receiving Water Turbidity Figure 7 Receiving Water Salinity Figure 8 Receiving Water Total Suspended Solids Figure 9 Receiving Water Nitrate and Nitrite Nitrogen Figure 10 Receiving Water Total Nitrogen Figure 11 Receiving Water Dissolved Reactive Phosphorous Figure 12 Receiving Water Total Phosphorous Figure 13 Receiving Water Faecal Coliforms Figure 14 Receiving Water Enterococci Figure 15 Drogue Monitoring Figure 16 Tin - Difference between sites Figure 17 Arsenic - Difference between sites Figure 18 Cadmium - Difference between sites Figure 19 Chromium - Difference between sites Figure 20 Copper - Difference between sites Figure 21 Lead - Difference between sites Figure 22 Mercury - Difference between sites Figure 23 Nickel - Difference between sites Figure 24 Zinc - Difference between sites Figure 25 Volatile Solids - Difference between sites v

8 Introduction 1.1 General Hastings District Council (HDC) was issued with a Resource Consent (CD130214W) on June 25, 2014, for the discharge of final treated wastewater through the long ocean outfall into Hawke Bay. This consent expires on 31 May The previous Consent CD990260Wd expired on the 31 March The purpose of this report is to assess compliance with Consent CD130214W. The method used to summarize the data and determine effects is listed in each section of this report. The numbers in parenthesis after each heading refers to the consent conditions that are being reported on in that section. The wastewater from Hastings district is reticulated to the Hastings District Council s Wastewater Facility at East Clive through a separated system of pipes which allow interchanging of flows for maintenance purposes. The flows are Domestic and Non Separable Industry (DNSI) which is composed mainly of domestic wastewater and industrial wastewaters. The Industrial Wastewaters are mainly organic in nature and contain no culturally offensive components (human waste). The DNSI is treated through Biological Trickling Filters (BTF) to remove the cultural offensiveness of the waste; the industrial wastewaters are screened through a 1mm slot. After treatment the two wastewater streams are combined to be discharged through the long ocean outfall (2.75Km) with the last 300m being diffuser. The report covers compliance with the conditions of the consent and compliance with the environmental guidelines (ANZECC 2000) which covers marine waters and was the basis for environmental acceptance of the discharge as set out in the Assessment of Environment Effects (Application Edition June 2013) prepared for the consent. Figure 1 HDC Wastewater Treatment - Flow paths 1

9 1.2 Abbreviations AEE Assessment of Environmental Effect ANZECC Australia and New Zealand Environment and Conservation Council AS Acid Soluble Avg Average (or Mean) BTEX Benzene, Toluene, Ethylbenzene and Xylene BTF Biological Trickling Filter BOD 5 day Carbonaceous Biochemical Oxygen Demand cbod5 5 day Carbonaceous Biochemical Oxygen Demand Cfu Colony forming units (of microorganisms) COD Chemical Oxygen Demand DNSI Domestic and Non Separable Industry (This is the wastewater to be treated by the BTF) DRP Dissolved Reactive Phosphorous FCW Final Combined Wastewater HBRC Hawkes Bay Regional Council HDC Hastings District Council ISQG Interim Sediment Quality Guideline g/m 3 grams per cubic meter (same as mg/l) l/s litres per second LOEC Lowest Observable Effect Concentration m meter m 3 cubic meters mg/l milligrams per litre (same as g/m 3 ) MOU Memorandum of Understanding NH3 Ammonia NH3N or NH4N Ammoniacal Nitrogen NH4 + Ammonium Ion NOEC No observed Effect Concentration NT Not Tested The sample was not tested for that particular parameter PLC Programmable Logic Controller SCADA Supervisory Control and Data Acquisition TEC Threshold Effect Concentration (Geometric mean of NOEC and LOEC) TN Total Nitrogen TOG Total Oil and Grease TP Total Phosphorous TSS (and SS) Total Suspended Solids Data Analysis and Interpretation 2.1 Analytical Results Where an analytical result is below the detection level, half of the detection level has been used in calculating averages, maximums and minimums. If all the results are below the detection level the results are shown as less than the detection level as there is no indication as to how close the results are to the detection level. For microbiological analyses if the analysis shows <1 then 1 has been used for numerical analysis. 2.2 Trend Analysis for Wastewaters The peer review for last year s report, suggested the use of the more formal Mann-Kendall test and the Sen Slope estimator to evaluate trends. This year we have used the Statistical program Time Trends. The analysis uses 4 seasons which align with the quarterly analyses, July to September, October to December, January to March, April to June. The data used for the analysis of trends for this annual report is from the start of the consent (1 July 2014) and uses the median value per season to assess trends. 2

10 Time Trends uses the Sen Slope estimator to identify the direction of the trend and the significance, for simplicity we have reported the percentage estimated annual change with probability of the trend being categorized as follows:- Probability <0.9 Probability 0.9 to 0.95 Probability 0.95 to 0.99 Probability 0.99 to Probability >0.999 Not Significant Weak Significant Strong Very Strong 2.3 Analysis of Sediments and Water Quality Monitoring The trend for each site and parameter has been analysed using Time Trends as described Section 2.3 of this report. In addition the results between sites will be will be analysed for differences between sites using a nonparametric method in Statistica 10 (Multiple comparisons of Mean Ranks for all samples) and using a probability of This is presented as a table of the identified difference between sites for each parameter. Box and whisker diagrams for the total data for the current consent provide a visual comparison between the sites. 2.4 Trend Analysis for Toxicity Testing The Threshold Effect Concentration has been used to assess trends using Time Trends as described in section 2.3. Compliance and Adverse Environmental Effects (24c) 3.1 Compliance with the Consent The assessment of compliance with each clause of the consent is contained in Section 3.3. Each of the consent conditions are addressed in Section 3.3 It has been graded as Compliant, Minor Non- compliance or Non-compliant. 3.2 Adverse Environmental Effects ANZECC 2000 has been used to provide an assessment of environmental effects. As the minimum dilution required by this consent is 100:1, the effect on the environment by the final combined wastewater has been assessed by comparing the parameters in the final combined wastewater with the ANZECC 2000 guidelines for toxicants for a typical slightly-moderately disturbed system. This provides an environment effect at the boil directly above the diffuser. Dilutions further away from the diffuser are significantly greater. 3

11 3.3 Compliance Assessment (24c) Conditions Compliance Comments 1 The Consent Holder shall discharge the final combined wastewater as authorised by this Resource Consent generally in accordance with the information supplied with the application. Where a conflict exists between the application and the conditions of this Resource Consent, the conditions shall prevail. 2 The rate of discharge of the final combined wastewater (see Advice Note 1) shall not exceed 2,800 litres per second. 3 The discharge of the final combined wastewater as authorised by this Resource Consent shall be by way of the existing long offshore outfall structure located at the end of Richmond Road, East Clive, and shall take place between approximately 2,450m and 2,750m offshore, being approximately NZMG The final combined wastewater discharged to Hawke Bay via the long offshore outfall shall pass through an ocean outfall diffuser which has been designed to achieve a minimum average dilution over the boil of not less than 100:1 on slack water. Wastewater Treatment Standards 5 The final combined wastewater discharged shall meet the following requirements: a) All separable industrial wastewater shall pass through a milliscreen having a maximum aperture slot width of 1mm. b) All domestic and non-separable industrial wastewater shall pass through a 3mm diameter hole size screening device or equivalent, followed by treatment in a biological trickling filter, with an annual average daily loading of carbonaceous biochemical oxygen demand (5 day test) (cbod5) that shall not exceed 0.4 kg per cubic metre of media, with the treatment plant managed in accordance with best wastewater engineering practice and industry standards, and: I. the media in the biological trickling filters shall consist of randomly packed plastic material that provides a specific surface area of not less than 90m2/m3, and II. ii) the wastewater remaining after that treatment, prior to being discharged, shall pass through the Rakahore channel. Full Full Full Full Full All plant is fully operational Two pumps at full speed have a maximum design flow of 2800 l/s. Maximum peak flow recorded was 1959l/s. Analysis of Flow data is in Section5.4.1 This is the location of the ocean outfall diffuser, the replacement diffuser is located alongside the existing diffuser so will be in the approximately the same location The existing diffuser diffuser was designed to meet these criteria, the replacement diffuser diffuser has been designed to meet these criteria. a) Industrial screening 1mm ContraShear Suboscreens b) Domestic screening 3mm Escamax screen Annual cbod5 average loading rate: 0.22 Kg/m 3 /day (maximum 0.35 Kg/m 3 /day) i) Media installed has a specified surface area of 100m 2 /m 3 ii) All treated wastewater passes through Rakahore channel 4

12 6 The final combined wastewater discharged shall meet the following standards: Analyte Maximum Concentration (g/m 3 ) Maximum Loading (Kg/day)* Chromium III Chromium VI Copper Zinc Cadmium Mercury Lead Nickel Ammonia * The maximum daily loading limit is based on the maximum treated wastewater concentration limits multiplied by the 75%ile wastewater flow rate (52,070m 3 /day) over 12 months in 1998 (a dry year). In the event that a limit is exceeded for any analyte, an additional 24 hour flow proportional sample shall be collected and tested for that analyte within 5 working days of receipt of the laboratory result. An investigation shall also be undertaken into the cause of the exceedence, and the findings of the investigation recorded and provided to the Regional Council (Manager Resource Use) within one month of the exceedence occurring. Full Maximum concentrations and loads Analyte Maximum Concentration (g/m 3 ) Maximum Loading (Kg/day) Chromium III Chromium VI Copper Zinc Cadmium Mercury < #2 Lead Nickel Total Ammonia N # #1 The term ammonia was changed to Total Ammoniacal N in the Errata Slip dated June #2 Calculated from half the detection level 5

13 7 The discharge of the final combined wastewater as authorised by this Resource Consent shall not cause any of the following effects beyond a distance of 750m from the midpoint of the outfall diffuser: a) The production of any conspicuous suspended materials; or b) Any conspicuous change in the colour or visual clarity; and shall not cause any of the following effects beyond a distance of 500m from the midpoint of the outfall diffuser: c) The production of any conspicuous oil or grease films, scums or foams, or floatable materials; or d) Any emission of objectionable odour; or e) Any significant adverse effects on aquatic life, or f) A change of the natural temperature of the receiving water by more than 3 degrees Celsius, or g) The Dissolved Oxygen concentration to be less than 80% of the saturation c h) Undesirable biological growths. 8 The average concentration of Total Oil and Grease in the final combined wastewater shall not exceed 200g/m3 over any 24 hour period based on the sampling procedure set out in Conditions 13 and The Consent Holder shall inspect the diffuser at least annually and at intervals not more than14 months apart, and at any other time as necessary, at which time any ports blocked by mussels or other debris will be cleared. The number of blocked ports shall be recorded and reported in the Annual Monitoring Report required by Condition 24 of this consent. 10 The Consent Holder shall ensure that all components of the wastewater treatment plant and outfall structures (including the diffuser on the long offshore outfall) are maintained in good working order, and in accordance with industry best practice guidelines. 11 The Consent Holder shall ensure that all sampling equipment, including meters and field measurement devices are maintained in good working order by suitably qualified persons in accordance with the manufacturer's instructions and industry best practice guidelines. Records of calibration shall be kept and made available to the Council (Manager Resource Use) upon request. 12 The Consent Holder shall continuously monitor and record the rate of discharge and the daily volume of the final combined wastewater is charged. The flow meters used to record the discharge shall have an accuracy within plus or minus 5%, as per the manufacturer's calibration records. Full Full Full Minor Non Compliance Full Full Each time sampling is carried out around the outfall diffuser (each quarter) visual and olfactory observations are made and recorded at 750m and 500m to the North and South of the diffuser as well as directly over the diffuser. No abnormalities in the colour, clarity, grease films, scums and floatable material or undesirable biological growths were reported. The maximum Total Oil and Grease recorded over the sampling period was 185 mg/l The inspection was initially not going to be carried out as the diffuser was to be replaced in the near future. There were delays in the tender process so an inspection was carried out on 26 July Bad weather prevented the inspection in June as was originally intended. The diffuser in in similar condition to the last inspection. A leak in the outfall was reported by HBRC staff. Repairs were carried out as quickly as practicable. A collar on the outfall had been damaged by an external force, the collar has been repaired. All equipment is calibrated to recognised standards. Flow reorders are difficult to calibrate and where possible a ruler measures height and a velocity meter measures the velocity. Comparisons between meters over a period of time provides a good indication of accuracy. Newer flow meters have been installed in the DSNI inlet, Total Treated Wastewater flow into the wet well and in the screened industrial flow. This allows a comparison between all flows. 6

14 13 For a period of 12 months, from the date of commencement of this consent, at quarterly intervals, with not less than 2 months between each sample, the Consent Holder shall take two flow proportional samples during each 24 hour period on a minimum of 7 consecutive days. The samples shall be taken from the following waste streams, and analysed for the constituents stated: a) The domestic and non-separable industrial wastewater prior to the biological trickling filter treatment. These samples shall be analysed for: i) Total suspended solids; ii) iii) Total oil and grease; and cbods. b) The domestic and non-separable industrial wastewater immediately after the biological trickling filter treatment. These samples shall be split into 2 separate samples which will be analysed separately. One sample shall be taken during the 21 hours of normal operation. One sample shall be taken during the 3 hours of the biomass flushing cycle. These samples shall be analysed for: i) Total suspended solids; ii) iii) Total oil and grease; and cbods. c) The final combined wastewater. These samples shall be analysed for the analytes listed, at the detection limit shown, in Schedule 1 (attached) for quarterly and annual sampling. 14 Starting 12 months from the date of commencement of this consent, at quarterly intervals, with not less than 2 months between each sample, the Consent Holder shall take 24 hour flow proportional samples on a minimum of 7 consecutive days of the following waste streams, and analyse them for the constituents stated: (a) The domestic and non-separable industrial wastewater prior to the biological trickling filter treatment. These samples shall be analysed for: i) Total suspended solids; ii) iii) Total oil and grease; and cbods. Not applicable to this report Full This clause no longer applies The average annual results for this monitoring is in Section 4 of this report Influent Results Total Suspended Solids (mg/l) 211 Total Oil and Grease (mg/l) 51.3 cbod5 (mg/l) 170 7

15 (b) (c) The domestic and non-separable industrial wastewater immediately after the biological trickling filter treatment. These samples shall be analysed for: i) Total suspended solids; ii) Total oil and grease; and iii) cbods. The final combined wastewater. These samples shall be analysed for the analytes listed, at the detection limit shown, in Schedule 1 (attached) for quarterly and annual sampling. 15 At quarterly intervals, with not less than 2 months between each sample, the Consent Holder shall test the toxicity of the final combined wastewater to at least three species of marine organisms to determine if there is a statistically significant effect. A plan outlining the proposed testing method and the organisms to be tested shall be submitted to the Regional Council (Manager Science) for approval within 2 months of the commencement date of this consent. Changes to the plan (including changes to the organisms tested) can be made but must be submitted to the Regional Council for approval before the proposed changes can be made. The interpretation of results and the actions shall be undertaken using an adaptive management approach as is detailed in the figure on Page 5 of the Consent. 16 At quarterly intervals, with not less than 2 months between each sample, the Consent Holder shall take water quality samples at 10 sites perpendicular to the centre of the diffuser at distances of 100m, 250m, 500m, 750m and 1000m (on each side of the diffuser). These samples will be analysed for faecal coliform and enterococci. Field measurements are to be made of ph, salinity, turbidity, temperature, and dissolved oxygen (%saturation) at each location as well. 17 While samples are being taken in accordance with Condition 16, a GPS drogue shall be placed at the centre of the diffuser to measure the surface currents for at least 30 minutes. 18 The Consent Holder shall undertake surveys designed to show the impact of the discharge on the benthic fauna: a) The benthic survey shall include an assessment of marine sediments, benthic ecology, and trace metals in flatfish (comparable to that carried out by Golders Associates in 2012 and 2013) and shall be undertaken in the 8 th, 17 th, and 26 th years after the commencement date of this Resource Consent. The final design of each survey shall be submitted to the Regional Council (Manager Science) for approval prior to each survey being undertaken. Flatfish of the same species Full Full 8 Effluent Results Total Suspended Solids (mg/l) 90 Total Oil and Grease (mg/l) 12.0 cbod5 (mg/l) 30.3 Results in Section 6 of the report, All results comply with the Adaptive Management Plan. Results are in Section 7 of this report. Full Tracks recorded are displayed in Section 7.2 Not applicable to this report This clause does not commence until 2022 which is outside the timeframe of this report, therefore compliance is not assessed

16 as those collected at the time of the first benthic survey required by this consent shall also be tested for pathogenic bacteria and parasites (see Advice Note 3). The results of all benthic surveys shall be provided to the Regional Council (Manager Resource Use) within 1 month of being received by the Consent Holder. 19 Twice during the year (summer and winter) the Consent Holder shall take seabed sediment grab samples at distances of approximately 250m, 500m and 750m to the north and 250m, 500m and 750m to the south of the midpoint of the outfall diffuser. Those samples shall be analysed for the analytes listed, at the detection limit shown, in Schedule 2. In the event that sediment monitoring required by this condition, results in two or more exceedances of ANZECC 2000 (ISQG - Low) sediment guidelines on one occasion of sampling, then an additional benthic survey shall be undertaken within one year of the sediment sampling exceedance(s) occurring. However, no more than one additional survey shall be required by this condition to be undertaken within each 9 year period specified in Condition 18 a). 20 All quality analysis of the wastewater discharged other than field measurements as required by the conditions of this consent shall be undertaken by an independent laboratory accredited to IANZ or other laboratory approved by the Regional Council (Manager Resource Use). Field measurements shall be undertaken in accordance with best industry practice. 21 Within three months of the commencement date of this consent, the Consent Holder shall submit to the Regional Council (Manager Resource Use) a Memorandum of Understanding (MOU) which shall include, but is not limited to the following: (a) Details of sampling methodologies and procedures to be followed; (b) Protocols that will be observed; (c) (d) Details of sampling locations; Details of when information (including data and sampling results) needs to be provided to the Regional Council, and in what format. The MOU shall be prepared in consultation with the Regional Council (Manager Resource Use) and can be varied upon agreement between the two parties. All sampling shall be undertaken in accordance with the MOU. All records Full Full 9 Samples are taken quarterly and the result are in Section 8 of this report Analyses carried out by Hill Laboratories (IANZ accredited) and NIWA Toxicology Laboratory Full An updated version of the MOU was sent to Andrew Gass on 17/2/2017 by . HDC will update the MOU when procedures or equipment changes.

17 collected in accordance with the conditions of this Resource Consent shall be provided to the Regional Council (Manager Resource Use) at the times and in the formats specified in the MOU. Until the MOU is prepared, records shall be provided to the Regional Council (Manager Resource Use) no more than one month following the end of the month to which they relate, except for the flow data required in accordance with Condition 12 of this consent which shall be provided at quarterly intervals. Administration 22 The Consent Holder shall ensure that at all times clear and visible signage is placed on the buoys marking the two ends of the diffuser, incorporating the words "Shellfish unfit for human consumption". 23 The Consent Holder shall appoint a person to be responsible for the dayto-day operation of the treated wastewater disposal system and to act as a contact person for the Regional Council. The name and phone number of this contact person shall be advised to the Regional Council (Manager Resource Use) within 10 working days of the commencement date of this consent and within 10 days of any change. 24 Before 1 October each year, the Consent Holder shall provide the Regional Council (Manager Resource Use) with an 'Annual Monitoring Report', covering the preceding 12 month period ending 30 June. The report shall be submitted together with a peer review completed by a suitably qualified and experienced professional expert. This monitoring report shall include, but not be limited to: a) A summary of all monitoring undertaken as required by this consent, and may include details of additional monitoring undertaken by the consent holder to better characterize the effects of the discharge on Hawke Bay; b) A critical analysis of the results of sampling required by Condition 13, in the Annual Monitoring Report completed the year following the collection of that data. c) A critical analysis of the monitoring information in terms of compliance and adverse environmental effects; d) An assessment of compliance in relation to the trigger values set out in the table below. Any exceedances of these trigger values shall be clearly identified and reasons for each exceedence (if known) provided. Comment shall also be provided about the significance of the exceedance in terms of effects (if any) on the receiving environment, and any measures that may be appropriate to reduce the concentration of the relevant analyte should that be necessary having regard to any adverse environmental effects. An assessment of trends in the concentrations of these parameters over the Full Full Full 10 The signage was replaced when the buoys were refurbished 3 contacts have been provided This report provides compliance. The annual average for the trigger values were: Analyte Trigger Value 2 cbod5 1 26,011 Kg/day Total Suspended Solids 1 22,496 Kg/day Total Daily (annual average) volume m 3 /day

18 previous year, and also over the term of this Resource Consent must also be provided; cbod5 1 Total Suspended Solids 1 Analyte Trigger Value 2 Total Daily (annual average) volume 48,000 Kg/day 39,000 Kg/day 66,000 m 3 /day 1 The annual average mass load is calculated by multiplying the result for each day by the volume each day and then averaging the loads. 2 The trigger value is calculated as an upper tolerance limit based on annual mean results from 1998 to 2013 inclusive. e) Comment on any non-compliances and operational problems, and any actions undertaken to address these; f) Details of any works undertaken or proposed to improve the performance of the treatment system, and the timeframe for completion of any proposed works; g) Identification and comment on any trends in volumes, flows, toxicity (EC50 or LC50) and contaminant loads over the reporting period, and compared to previous years. This shall include any trends in water quality parameters/wastewater constituents including comment on the potential environmental implications of these trends; and h) Recommendations regarding alterations or additions to the monitoring programme; i).details of any changes to the consent conditions that may be applied for within the next 12 month period; j) Details of the date of the plant open day, numbers in attendance, and written questions submitted by members of the public, and responses given (except that this subsection cannot be addressed in the first Annual Monitoring Report completed in accordance with the conditions of this consent); and k) The tabulated results of the laboratory analytical monitoring. 25 Each Annual Monitoring Report shall be made publicly available on the Consent Holder's website within one month of it being lodged with the Regional Council (Manager Resource Use). Notification of the availability of this Report shall also be included in the Consent Holder's next public newspaper general ratepayers' notice and also the next ratepayer newsletter. Minor Non Compliance The availability of the Annual Report was not included in a ratepayer newsletter but notification was placed on the Council website, in the newspaper and radio advertisements 26 During the month of November each year, the Consent Holder shall have a public 'open day' at the Wastewater Treatment Plant site, located on Richmond Road. Notification of this open day shall be done via the Consent Holder's website and in a Consent Holders public newspaper Full The Open Day was held on 26/11/ People attended and there were no official requests for further information.

19 general ratepayers' notice at least 10 working days before the open day. The open day shall be attended by Hastings District Council Staff as well as a Regional Council Compliance Officer. The purpose of the open day is to give the community an opportunity to view the treatment plant, and discuss the Annual Monitoring Report. It is also an opportunity for members of the public to submit written questions to which the Consent Holder shall respond in writing within one calendar month. Details of the date of the open day, numbers in attendance, written questions submitted and responses given shall be included in the next Annual Monitoring Report, as noted in Condition 24(j) above. 27 The Consent Holder shall submit to the Regional Council (Manager Resource Use) a Trends, Technology, Discharge, Environmental and Monitoring Review Report not later than the 9 th, 18 th and 27 th year anniversaries of the issue of this discharge permit. Each Review Report shall be made publicly available on the Consent Holder's website within one month of being lodged with the Regional Council. Notification of the availability of this Report shall be included in the Consent Holder's next public newspaper general ratepayers' notice and also the next ratepayer newsletter. The Review Report shall address as a minimum, but not be limited to, the following matters for the nine year period since the last review: a) Comparisons of population and industrial changes and possible trends as compared to the Heretaunga Plains Urban Development Strategy (2010) (HPUDS), and then latest reports on the Hastings Urban Development Strategy and the Hastings Industrial Strategy; b) Volumes, flows and loads profile and changes assessed against future projections and wastewater projections as set out in section 4.3 of the Hastings Wastewater Resource Consents Project: Assessment of Effects n the Environment and Resource Consent Applications copy dated June 2013; c) Trade waste profiles, trends and any significant changes in the Consent Holder's trade waste management practices and the trade waste contaminant profile; d) Any new changes to environmental guidelines and I or standards applicable to the discharge of treated wastewater into Hawke Bay; Not applicable to this report Comments made on the sign in sheet were:- Very Educational Thank You Good system working well Very interesting & Informative Thanks heaps Very interesting more information about the open day via advertising would have been better. Great thank you. Road closed sign was disconcerting It is noted the information on the availability and the date of the open day was not included in the rates demand. The dates the rates demands are sent out do not align well with advertising the open day. See Section 12 Compliance cannot be assessed until after the 8 th anniversary of the consent issue, that is 25 th June

20 e) Changes in asset management and operational matters that may have relevance to the on-going operation and development of the Consent Holder's Wastewater Scheme from the perspective of the treated wastewater discharge, water conservation and efficient energy management; f) Changes in wastewater treatment technologies that may be relevant to the Hastings Wastewater Scheme for either the domestic and non-separable waste stream and I or the industrial waste stream; g) The results of a recreational usage survey undertaken during the nine year period, which is comparable to the survey undertaken between the summers of 2011 and 2013 (See Advice Note 4), and comparison of those results with previous surveys; h) Options for treated wastewater disposal I discharge and beneficial reuses that may be appropriate to the Wastewater Scheme; i) i) Effects of the treated wastewater discharge into Hawke Bay as evident from the resource consent monitoring; and j) Details of consultation undertaken with the community to ascertain their views of the effects of the current wastewater discharge (see Advice Note 5). 28 Consideration of this existing Resource consents project objectives, opportunities for improvement and Best Practicable Option (BPO) in terms of the interpretation of this term in the Resource Management Act The Consent Holder shall log all complaints received relating to the discharge. The log shall include: a) The date and time of the complaint; b) The nature of the complaint; c) The name, telephone number, and address of the complainant; d) Weather and sea condition information (including an estimate of wind speed and direction, and description of sea condition); e) Details of key operating parameters at the time of the complaint; and f) Any remedial action taken to prevent further incidents. Full There have been no complaints in relation to this consent. There has been no odour complaints Complaints shall be reported to the Regional Council (Manager Resource Use) within 24 hours of receipt, and the log of complaints shall be made available to the Regional Council (Manager Resource Use) on request. Any complaints relating to potential adverse health effects associated with exposure to the wastewater discharge shall be notified to the Hawke's Bay District Health Board within 24 hours of receipt also. 29 In accordance with the principles of the Treaty of Waitangi (especially those of partnership and consultation) and recognising the role of Tangata Whenua as Kaitiaki, the Consent Full 13 The Hastings District Council Tangata Whenua Wastewater Committee is an official committee of Council constituted under the committee provisions of the Local Government Act The 2014_15 Annual

21 Holder shall establish, and retain, as a committee of the Hastings District Council under Clause 31, Schedule 7, Local Government Act 2002, a Council Committee, half of the members of which shall be Tangata Whenua representatives the functions of which shall include: a) Developing the Hastings District Council's wastewater treatment and disposal system policies; b) Receiving, reviewing and recommending action on reports concerning the operation and performance of the Council's wastewater disposal system, treatment plant and ocean discharge; c) Receiving, reviewing and recommending from time to time the comm1ss1oning of reports and future Hastings District Council actions on wastewater issues including: i. Options for further or other treatments; ii. Options for alternative methods of disposal; and iii. Monitoring effects on the environment; d) Co-ordinating and overseeing education of the community including Tangata whenua and trade waste dischargers on wastewater issues; e) Not less than three months before each of the Trends, Technology, Discharge, Environmental and Monitoring Nine Yearly Review as required in accordance with Condition 27 is commenced by the Consent Holder, providing to the Consent Holder any further suggested input in respect to the scope of the review; f) Advising the Consent Holder on the Condition 27 Trends, Technology, Discharge, Environmental and Monitoring Nine Yearly Review before it is finalised and submitted to the Regional Council (Manager Resource Use) (See Advice Note 6); and g) Recognising the role of Tangata Whenua as Kaitiaki and the need to recognise and seek to satisfy the cultural concerns of Tangata Whenua. 30 In the event of the Consent Holder becoming aware of: a) unusual or extreme circumstances (not being circumstances such as would provide a defence under sections B, Resource Management Act 1991) that may lead to one or more of the conditions of this Resource Consent being breached, or b) circumstances having occurred that have, or could, lead to oncompliance, immediate notification of such problems shall be made to the Regional Council (Manager Resource Use). This notification shall include, but not be limited to, provision of the following information as far as such information is known to the Consent Holder at that time: Full Report was presented to this committee on Tuesday 10 November The HBRC was notified of and kept informed on progress with the outfall repair. 14

22 i. The extent of non-compliance if it has occurred, including the duration of non-compliance, volume discharged during that period, and the nature and quality of the discharge; ii. The immediate and further planned measures being undertaken to minimise and mitigate any adverse effects of the noncompliance; iii. The Consent Holder's assessment of public health risk arising from the event including advice received from the Hawke's Bay District Health Board Chief Executive Officer and Medical Officer of Health; and iv. Updating the Regional Council (Manager Resource Use) at not greater than 24 hourly intervals of the current situation until the problems are rectified and the Consent Holder is compliant with the Resource Consent conditions. 31 Within one calendar month of any unforeseen event that resulted in noncompliance with the conditions of this Resource Consent, the Consent Holder shall provide a further report to the Regional Council (Manager Resource Use). This report shall include, but not be limited to the provision of any further information on the reasons for the noncompliance and the measures investigated and put in place or to be put in place to avoid or at least minimise the possibility of any similar problems in the future that may cause non-compliance. 32 The Consent Holder shall make available to the Regional Council (Manager Resource Use) upon request records kept in relation to the discharge, and its effects on the environment including sampling, testing, and analysis. Full Full 15

23 Domestic and Non-separable Industry (DNSI) Monitoring Results 4.1 Summary of Monitoring Undertaken (24a) A flow pulse is generated every 100m 3 which drives a sampler. One sampler is situated prior to the BTF pump station, after screening has taken place. The sampler is located just after the control flume in the screening channel. The second sampler is located in the outlet chamber of both BTF s and is an area of high turbulence (good mixing). The samplers are run continuously for 7 days with containers being exchanged at 8am each morning. Each container is mixed and subsamples taken, the samples are chilled, preserved or frozen as required for each test. The samples are then couriered to Hill Laboratories for analysis for: Total Suspended Solids 5 Day Carbonaceous Biochemical Oxygen Demand Chemical Oxygen Demand Total Oil and Grease. The sampling was undertaken on the following days: Quarter 1 8 September 2016 to 15 September 2016 Quarter 2 18 November 2016 to 26 November 2016 Quarter 3 20 February 2017 to 27 February 2017 Quarter 4 4 May 2017 to 11 May Biological Trickling Filter Treatment (24b & 13) The results listed are for the average of the 7 day sample taken each quarter. Table 1 DNSI Wastewater Total Suspended Solids (mg/l) cbod5 (mg/l) COD (mg/l) Total Oil and Grease (mg/l) 8 to 15 September to 25 November to 27 February to 11 May Table 2 BTF Treated Wastewater Results Total Suspended Solids (mg/l) cbod5 (mg/l) COD (mg/l) Total Oil and Grease (mg/l) 10 to 17 September to 21 December March to 11 April June to 23 June

24 4.3 BTF Treatment Performance (24b) The design of the plant was to achieve a reduction in suspended roughly equivalent to Primary Treatment (the original consenting option). Table 8 shows the percentage reductions in the parameters being measured. Table 3 BTF Plant performance (% Reduction) TSS (mg/l) cbod5 (mg/l) COD (mg/l) TOG (mg/l) Quarter Quarter Quarter Quarter Annual The plant is slightly underperforming in Total Suspended Solids Reduction but is maintaining a high BOD reduction. 4.4 Trend Analysis DNSI and BTF Treated Wastewater (24d) Time Trends has been used to assess trends for DNSI Total Suspended Solids, DNSI cbod5, DNSI COD, DNSI Total Oil and Grease, BTF Treated Wastewater Total Suspended Solids,, BTF Treated Wastewater cbod5, BTF Treated Wastewater COD, BTF Treated Wastewater Total Oil and Grease, Total Suspended Solids Reduction, cbod5 Reduction, COD Reduction, Total Flow and Loading Rate. Table 4 DNSI and Treated BTF Wastewater Trends Trend Direction % Annual Change Trend Strength Trend Graph Flow Increasing 3.00 Weak BTF Treated Wastewater Total Suspended Solids Increasing 3.55 Weak BTF Treated Wastewater COD Increasing 6.87 Significant 17

25 Trend Direction % Annual Change Trend Strength Trend Graph BTF Treated Wastewater Total Oil and Grease Increasing Very Strong 4.5 Assessment of Effects of the BTF Treated Wastewater The DNSI treatment is well below the annual average loading rate required by the consent. There has been an increasing load for the treated COB and Total Oil and Grease which indicates the treatment performance is slightly down. The BOD removal remains about the same so the plant continues to operate and provide the cultural treatment of the DNSI before discharge through the 2.75 Km long ocean outfall. Final Combined Wastewater (FCW) Quality & Quantity Monitoring Results 5.1 Summary of Monitoring Undertaken (24a) A pulse is generated every 200m 3 which drives a sampler. The sampler is located on the outlet of one of the ocean outfall pumps; this provides an area of high turbulence (good mixing). The samplers are run continuously for 7 days with containers being exchanged at 8am each morning. Each container is mixed and subsamples taken, the samples are chilled, preserved or frozen as required for each test. Testing is carried out at time of sampling for ph and conductivity. The quarterly samples are then couriered to Hill Laboratories for analysis for: Total Oil and Grease (TOG) Total Suspended Solids (TSS) Ammoniacal Nitrogen (NH3N) 5 Day Carbonaceous (BOD) Sulphide Dissolved Reactive Phosphorous (DRP) Acid Soluble Metals (Zinc,Arsenic,Chromium III,Copper, Nickel, Lead, Mercury) Chromium VI. (CrVI) The Annual sampling (taken every 9 months), in accordance with the resource consent condition (14c) which requires annual sampling; samples were taken in Quarter 3 and were analysed by Hill Laboratories for the quarterly analysis and the following analyses: Total Solids (TS) Total Organic Carbon (TOG) Nitrate/Nitrite Nitrogen Chemical Oxygen Demand Total Kjeldahl Nitrogen (TKN) Total Phosphorous (TP) Total Metals (Zinc,Arsenic,Chromium III,Copper, Nickel, Lead, Mercury) Dissolved Metals (Zinc,Arsenic,Chromium III,Copper, Nickel, Lead, Mercury) 18

26 Total Phenols Total Cyanide Volatile Organic Compounds (including benzene, toluene, ethylbenzene, and xylenes) [VOC] Semi Volatile Organic Compounds (SVOC) Pentachlorophenols Organonitrogen and Organophosphorous pesticides The sampling was undertaken on the following days: Quarter 1 10 September 2015 to 17 September 2015 Quarter 2 14 December 2015 to 21 December 2015 Quarter 3 28 March 2016 to 30 March 2016, 6 April 2016 to 11 April 2016 (Sampling was interrupted due to a family bereavement) Quarter 4 16 June 2016 to 23 June Final Combined Wastewater Results (24c & 13c) The results are for the 7 day average, the comparison of individual results with the consent limit is in Section 3 of this report Table 5 Final Combined Wastewater Results Analysis Consent Limit Quarter 1 Quarter 2 Quarter 3 Quarter 4 Annual Flow (m 3 /day) ph Conductivity (ms/m) Total Suspended Solids (mg/l) Total Oil and Grease (mg/l) cbod5 (mg/l) COD (mg/l) NH3N (mg/l) NH3N (Kg/day) DRP (mg/l) Total Sulphide (mg/l) AS Arsenic (mg/l) AS Cadmium (mg/l) AS Cadmium (Kg/day) AS Chromium III (mg/l) AS Chromium III (Kg/day) Chromium VI (mg/l) Chromium VI (Kg/day) AS Copper (mg/l) AS Copper (Kg/day) AS Lead (mg/l) AS Lead (Kg/day) AS Nickel (mg/l)

27 AS Nickel (Kg/day) AS Zinc (mg/l) AS Zinc (Kg/day) AS Mercury #1 (mg/l) AS Mercury #1 (Kg/Day) #1 all the results were below the detection level. The following tables list the average for the additional tests for the annual sample. For the metals the Acid Soluble results have been included for comparison and the average is for the 7 days. For the organic compound analyses only the compounds returning a positive analysis are recorded. The results are reported as the compound, the number of positive results in the 7 days, the average result of the positive samples and the maximum recorded value. Table 6 Final Combined Wastewater Annual Results Excluding Organics (additional analyses) Analysis Result Quarter 1 Result Quarter 4 Total Solids (mg/l) Total Organic Carbon (mg/l) Nitrite N (mg/l) Nitrate N (mg/l) Nitrate-N + Nitrite-N (mg/l) Chemical Oxygen Demand (mg/l) Total Kjeldahl Nitrogen (mg/l) Total Phosphorous (mg/l) Total Arsenic (mg/l) AS Arsenic (mg/l) Dissolved Arsenic (mg/l) Total Cadmium (mg/l) AS Cadmium (mg/l) Dissolved Cadmium (mg/l) Total Chromium [Total] (mg/l) AS Chromium [AS] (mg/l) Dissolved Chromium (mg/l) Total Copper (mg/l) AS Copper (mg/l) Dissolved Copper (mg/l) Total Lead (mg/l) AS Lead (mg/l) Dissolved Lead (mg/l) Total Nickel (mg/l) AS Nickel (mg/l) Dissolved Nickel (mg/l) Total Zinc (mg/l) AS Zinc (mg/l)

28 Dissolved Zinc (mg/l) Total Mercury (mg/l) # # #1 AS Mercury (mg/l) # # #1 Dissolved Mercury (mg/l) # #1 Total Phenols (mg/l) Total Cyanide (mg/l) #1 all results are below the detection level ( ) Table 7 Final Combined Wastewater Annual Results Quarter 1&4 Organics Volatile Organic Compounds (incl. BTEX) Compound No. Positive Average Maximum Toluene Chloroform (trichloromethane) Carbon Disulphide Semi Volatile Organic Compounds Compound No. Positive Average Maximum 3&4 Methylphenol (m&p Cresol) Phenol Chloro-3-methylphenol Pentachlorophenols No positive results Organonitrogen and Organophosphorous pesticides Diazinon Diuron Assessment of Compliance with Trigger Values (24c & 24d) Table 8 Compliance with Trigger Values Trigger Value (Condition 24) Trigger Value (this year s average) Trend (Section 5.4) cbod5 48,000 Kg/day 26,011 Kg/day Not significant Total Suspended Solids 39,000 Kg/day 22,496 Kg/day Increasing Total Daily (annual average) volume 66,000 m 3 /day m 3 /day Not significant The trigger levels have been complied with. 21

29 5.4 Trend Analysis (24d & 24g) Table 9 Final Combined Wastewater Trends Trend Direction % Annual Change Trend Strength Trend Graph cbod5 Decreasing Strong Total Suspended Solids Load Increasing 5.04 Weak Total Oil and Grease Load Increasing 6.37 Significant COD Load Increasing 2.26 Weak Acid Soluble Arsenic Load Increasing Significant 22

30 Trend Direction % Annual Change Trend Strength Trend Graph Acid Soluble Cadmium Load Increasing 9.40 Significant Acid Soluble Lead Load Increasing 4.91 Weak Acid Soluble Zinc Load Increasing 7.63 Significant Acid Soluble Mercury Load #1 Increasing 0.88 Weak 5.5 Assessment of Effects of the Final Combined Discharge The Final Combined Discharge complies with all the contaminant levels required by the consent. There are some increasing and decreasing trends and the discharge complies with the ANZECC 2000 guidelines when allowance is made for the 100:1 dilution at the diffuser. 23

31 Combined Wastewater Toxicity Assessment 6.1 Summary of Monitoring Undertaken (24a) Toxicity samples are taken once every quarter, if the timing with the NIWA, who carry out the toxicity testing, can be arranged one of the 7 day Final Combined Wastewater sample is used. This allows for extra information to be available if required. Toxicity samples (as required by the consent) were taken on: 8am 22 to 8am 23 September am 19 to 8am 20 January am 13 to 8am 14 April am 29 to 8am 30 June 2015 Each sample is tested against the following: Marine algae (Minutocellus polymorphus 48 hour growth test) Wedge shell (Macomona Liliana-96 hour survival and burial test) Blue mussel embryo test (Mytilus galloprovincialis 48 hour embryo development test) 6.2 Analysis of Results (24g) The results are reported as the No-toxicity dilution which is calculated as (1/TEC*100). The results are then assessed using the adaptive management plan (Condition 15 of the consent). The Adaptive Management Plan provides a decision tree to assist in deciding the risk to the environment based on various criteria, the decision tree is in Appendix B Table 10 Toxicity Results Algae Wedge Shell Wedge Shell Blue Mussel September 2016 & September h acute survival 60 minute reburial Embryo NR <5 < November <5 < February <5 <5 NR 8-9 May 2017 & June 2017 NR 1 = No result, the test did not meet the acceptability criteria 17 <5 <5 141 There was one results in excess of 1 in 200, based on the decision tree in Appendix B no further action was required on any sample 6.3 Toxicity Trend Evaluation The Time Trends analysis of the TEC and NOEC show no evidence to suggest either an increasing or decreasing level of toxicity. 24

32 Receiving Water Quality Monitoring Results 7.1 Summary of Monitoring Undertaken (24a) Measurements were taken around the outfall using a multiparameter probe for ph, temperature, Dissolved Oxygen, Salinity, and Turbidity (YSI ProDSS probe) at the locations prescribed in the consent. In addition we have added sites 2000m either side of the outfall as suggested in the last Annual Report. Samples were taken in front of the river mouths, approximately 50m offshore. Those measurements were taken approximately 150mm below the surface. Two one litre samples were also taken, this was subsampled into bottles which were preserved and refrigerated and sent to Hill Laboratories for analysis of Faecal Coliforms, Enterococci, Suspended Solids, Ammoniacal Nitrogen, Nitrate plus Nitrite Nitrogen, Total Nitrogen, Dissolved Reactive Phosphorous and Total Phosphorous Figure 2 Water Quality Sampling Sites Samples were taken on: 14 September November February May 2017 At the same time as the samples were taken a drogue was deployed at the centre of the diffuser. A GPS tracks the position of the drogue every 1 minute. At the end of the sampling run, the drogue is recovered 25

33 7.2 Analysis of Results (24c) Table 11 Average levels for 2017 Site ph Temperature Dissolved Oxygen Turbidity Salinity Log Faecal Coliforms Log Enterococci Suspended Solids Ammoniacal Nitrogen Nitrate/Nitrite Nitrogen Total Nitrogen Dissolved Reactive Phosphorous Total Phosphorous C % NTU PSU Cfu/100ml Cfu/100ml mg/l mg/l mg/l mg/l mg/l mg/l Ngaruroro m North m North m North m North m North m North m South m South m South m South m South m South Tukituki

34 7.3 Assessment of Differences between Sites Based on the Statistica analysis there were no statistical differences between sites for any of the parameters. The following box and whisker diagrams shoe the levels found for each site and parameter. A box and whisker diagram has not been prepared for Ammoniacal Nitrogen as the majority of results were below detection level. Figure 3 Receiving Water ph Figure 4 Receiving Water Temperature Figure 5 Receiving Water Dissolved Oxygen (%) 27

35 Figure 6 Receiving Water Turbidity Figure 7 Receiving Water Salinity Figure 8 Receiving Water Total Suspended Solids 28

36 Figure 9 Receiving Water Nitrate and Nitrite Nitrogen Figure 10 Receiving Water Total Nitrogen Figure 11 Receiving Water Dissolved Reactive Phosphorous 29

37 Figure 12 Receiving Water Total Phosphorous Figure 13 Receiving Water Faecal Coliforms Figure 14 Receiving Water Enterococci 30

38 Figure 15 Drogue Monitoring 7.4 Assessment of Effects (24c) There were no statistical differences between any site for any parameter indicating the receiving water is similar for each site including those sites close to the outfall and the river mouths. The box and whisker diagrams show some localised changes that could be attributable to the outfall or the rivers but they are not statistically significant. Marine Sediment Quality Monitoring Results 8.1 Summary of Monitoring Undertaken (24a) The consent requires samples of the sediment to be taken twice per year. HDC takes samples each time it visits the outfall for receiving water monitoring. Sampling was undertaken on: 14 September November March May 2017 The sites are perpendicular to the diffuser as follows North 750m from the centre (N750) North 500m from the centre (N500) North 250m from the centre (N250) South 750m from the centre (S750) South 500m from the centre (S500) South 250m from the centre (S250) 31

39 The samples were taken using a mini ponar dredge and placed in a container in a chilly bin. Each sample was subsampled and sent Hill Laboratories for the following analyses: Total Arsenic Total Cadmium Total Chromium Total Copper Total Nickel Total Mercury Total Zinc Total Tin Volatile Solids (not required by the consent). This provides an indication of organic matter around the outfall Particle Size (>2mm, 63microns to 2mm and <63 microns). Many of the metals can be incorporated with the mud (<63 microns) fraction so it allows a comparison with mud levels. 32

40 8.2 Analyses of results (24c) Table 12 Sediments - Metals Analysis 2016/17 Average (Maximum in parenthesis) Site Tin Arsenic Cadmium Chromium Copper Lead Mercury Nickel Zinc mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg mg/kg dry weight dry weight dry weight dry weight dry weight dry weight dry weight dry weight dry weight ISQG Low m North 1.00 (1.16) 5.23 (7.00) (0.052) (25.00) 9.53 (11.60) (14.5) (0.105) (14.50) (59.0) 500m North 1.04 (1.29) 5.15 (5.50) (0.052) (23.00) 8.83 (10.70) (11.60) (0.090) (12.20) (55.00) 250m North 1.15 (1.20) 5.10 (5.50) (0.063) (30.00) (11.30) (12.70) (0.132) (13.10) (56.00) 250m South 1.65 (2.10) 5.68 (6.30) (0.138) (50.00) (15.00) (12.60) (0.117) (13.70) (67.00) 500m South 1.23 (1.51) 5.58 (6.50) (0.078) (34.00) (14.50) (15.20) (0.103) (15.40) (67.00) 750m South 1.00 (1.08) 5.13 (5.60) (0.053) (27.00) 8.60 (9.30) (11.60) (0.078) (11.10) (48.00) 33

41 Table 13 Sediments - Volatile Solids & Grain size - Average (maximum in parenthesis) Site Volatile Solids Greater than 2mm 2mm to 63 microns Less than 63 microns mg/kg g/100g g/100g g/100g dry weight dry weight dry weight dry weight 750 m North 4.43 (4.90) < (12.7) 90.8 (95.5) 500m North 4.25 (4.60) 0.3 (0.7) 16.0 (18.6) 83.7 (86.6) 250m North 4.55 (5.10) 0.2 (0.4) 10.1 (14.8) 89.8 (93.0) 250m South 5.35 (5.70) 1.6 (3.0) 18.7 (30.9) 79.8 (88.9) 500m South 4.93 (5.50) 0.7 (1.0) 12.3 (18.8) 87.1 (90.9) 750 South 4.25 (4.60) 0.2 (0.4) 14.1 (15.9) 85.8 (87.6) 34

42 8.3 Assessment of Difference between sites Table 14 Tin Difference between sites Figure 16 Tin - Difference between sites Table 15 Arsenic - Difference between sites Figure 17 Arsenic - Difference between sites 35

43 Table 16 Cadmium - Difference between sites Figure 18 Cadmium - Difference between sites Table 17 Chromium - Difference between sites Figure 19 Chromium - Difference between sites 36

44 Table 18 Copper - Difference between sites Figure 20 Copper - Difference between sites Table 19 Lead - Difference between sites Figure 21 Lead - Difference between sites 37

45 Table 20 Mercury - Difference between sites Figure 22 Mercury - Difference between sites Table 21 Nickel - Difference between sites Figure 23 Nickel - Difference between sites 38

46 Table 22 Zinc - Difference between sites Figure 24 Zinc - Difference between sites Table 23 Volatile Solids - Difference between sites Figure 25 Volatile Solids - Difference between sites 39

47 8.4 Assessment of trends (24c) Table 24 Sediments - 750m North - Trends Trend Direction Probability Trend Strength Trend Graph Arsenic Increasing Weak Chromium Increasing Weak Volatile Solids Increasing Significant Table 25- Trends Sediments - 500m North Trends Trend Direction Probability Trend Strength Trend Graph Tin Increasing Significant Chromium Increasing Significant 40

48 Volatile Solids Increasing Strong Table 26 Sediments - 250m North Trends Trend Direction Probability Trend Strength Trend Graph Tin Increasing Significant Cadmium Increasing Significant Chromium Increasing Strong Copper Increasing Significant Lead Increasing Significant 41

49 Mercury Increasing Strong Nickel Increasing Significant Zinc Increasing Significant Table 27 Sediments - 250m South Trends Trend Direction Probability Trend Strength Trend Graph Chromium Increasing Significant Table 28 Sediments - 500m South Trends Trend Direction Probability Trend Strength Trend Graph Cadmium Increasing Significant 42

50 Chromium Decreasing Weak Zinc Decreasing Significant Volatile Solids Decreasing Weak There are no trends for 750m South. 8.5 Assessment of Effects (24c) The sediment analyses shoe some differences between sites but there is no commonality between different parameters. The box and whisker diagrams show an elevation of some levels to the south of the outfall. There are both increasing and decreasing trends for some of the parameters. Overall the sediments comply the ANZECC 200 sediment quality guidelines. Treatment Plant Performance and Improvements 9.1 Treatment Plant Performance (24c 24e) This section relates to the overall performance of the plant and the discharge through the long ocean outfall. The performance of the BTF is covered in Section 3.4. Over the past year the plant has performed well, the volumes discharged are well below the design of the plant and are compliant with the discharge rate in the consent. The trigger values for Flow, Total Suspended Solids and BOD have not been exceeded 9.2 Non Compliance (24c) The compliance with the consent is listed in Section 3. Compliance with the consent has been very good. There was a non-compliance with Condition 25, the availability of the Annual Report was not included in a ratepayer newsletter with the rates demand. A newsletter is only included in the first rate demand of the year (July), unless a separate newsletter is prepared this is not practical. The public notice published in the papers made reference to the Annual Report. 43

51 9.3 Operational Matters (24c) BTF Distributor The distributor arms have been modified to allow the removal of grit on each rotation. The water discharged is passed over a 0.5mm static screen to remove the particles from the wastewater Septage Treatment The new modifications are working very well with very few breakdowns DNSI Screening Modifications to the screens are continuing to decrease the quantity of fine material that appears to bypass the screen during the cleaning cycle Sewer Relining Further sewers have been relined Outfall Repairs The damaged collar on the outfall has been repaired. The diffuser is currently being replaced Industrial Screening We have installed a trial Nogerath screw press to provide improved dewatering of the solids. If successful a second unit will be installed to replace the current screw conveyors which require a major refurbishment. 9.4 Odour Odour at the Plant Boundary (Odour Management Plan) There have been no odour complaints Odour issues with the Discharge (7d) There are no issues of odours at the edge of the 500m mixing zone around the long ocean outfall. On occasions an odour can be detected above the boil, as soon as you move away from the outfall the odour disappears. 9.5 Improvements (24f) Currently we are investigating the replacement of the control systems for the plant as the current system is in a redundancy cycle. Recommendations for Future Monitoring (24h) The current monitoring provide a good level on information on the wastewater, the receiving environment and the sediments Proposed changes to Consent Conditions (24i) 11.1 Condition 6 Ammonia should be changed to Ammoniacal Nitrogen to comply with the ANZECC 2000 Guidelines (Errata Slip issued June 2005). This change was suggested in the last report but has not been implemented. 44

52 11.2 Condition 15 The cost of carrying out the toxicity test is currently $34,500 (excl. GST) per annum currently and will increase to $41,764 (excl. GST) for the coming year. These are extremely expensive tests on one sample per quarter and the value of the data is questionable. Hastings District Council has now been carrying out these tests for over 20 years and has demonstrated that the theoretical risk (based on 200:1 dilution) is low. As the cost of testing is significant HDC suggests a change to annual testing may be appropriate. If the change is made to annual testing HDC suggests an additional condition be added that if any samples exceed the consented requirements a sample shall be sent for toxicity testing during the next sampling period. This would be trigger level type approach as is currently being used for Flow, TSS Load and cbod5 load. This approach is becoming common practice in wastewater discharge consents. I am still awaiting comments from HBRC on this condition Condition 24 (d) In the table I would suggest annual average be added after cbod5 and Total Suspended Solids. Both these are described in note 1 to the table as annual average and this may avoid confusion in the future. This change was suggested in the last report but has not been implemented Condition 25 I would suggest the last sentence be changed to: Notification of the availability of the Annual Report shall be included in the Public Notice advertising the Open Day. Comment on Open Day (24j) The Open Day was held on 26/11/ People attended and there were no official requests for further information. Comments made on the sign in sheet were:- Very Educational Thank You Good system working well Very interesting & Informative Thanks heaps Very interesting more information about the open day via advertising would have been better. Great thank you. Road closed sign was disconcerting The open days have been well received by the public who are generally impressed by the plant. This year we invested in more radio advertising to alert the public of the open day. The next open day will be held on Saturday 11 November 2016 between 10am and 1pm Report Conclusions Overall the current treatment and discharge through the long offshore ocean outfall provides for an environmentally and culturally acceptable, sustainable and economic solution for wastewater from the Hastings District Council. 45

53 Appendix A - Tabulated data results (24k) Table 29 Final Combined Wastewater Daily Flow Measurements Page 46

54 Table 30 Final Combined Wastewater Peak Flow Rate Measurements Page 47

55 Table 31 DNSI and Treated Wastewater from BTF Results Page 48

56 Table 32 Quarterly Analysis Final Combined Wastewater Results Page 49

57 Table 33 Final Combined Wastewater Organonitrogen and Organophosphorous Pesticides Results Page 50

58 Page 51

59 Table 34 Final Combined Wastewater Volatile Organic Compounds Results Page 52

60 Page 53

61 Table 35 Final Combined Wastewater Semi Volatile Organic Compounds Results Page 54

62 Page 55

63 Table 36 Final Combined Wastewater Polychlorinated Byphenols Results Page 56

64 Table 37 Annual Final Combined Wastewater Results (Does not include Quarterly Analyses) Page 57

65 Table 38 Sediments Total Recoverable Metal Results Page 58

66 Table 39 Receiving Water Monitoring Results Page 59

67 Table 40 Receiving Water Microbiological Monitoring Results Page 60

68 Table 41 Receiving Water Drogue Monitoring Results Table 42 Final Combined Wastewater Toxicity Monitoring Results Table 43 Odour Complaints Received No odour complaints were received Page 61