AGENDA

Ordinary meeting of the

 

Nelson Regional Sewerage Business Unit

 

 

Friday 11 December 2015
Commencing at 1.00pm
Ruma Mārama

Level 2A, Civic House

110 Trafalgar Street, Nelson

 

Membership: Nelson City Councillor Ruth Copeland, Mr Derek Shaw, Tasman District Councillors Barry Dowler and Michael Higgins

 

Representatives: M Hippolite (Iwi Representative) and P Wilson (Industry Customers Representative)


Guidelines for councillors attending the meeting, who are not members of the Committee, as set out in Standing Orders:

·      All councillors, whether or not they are members of the Committee, may attend Committee meetings (SO 2.12.2)

·      At the discretion of the Chair, councillors who are not Committee members may speak, or ask questions about a matter.

·      Only Committee members may vote on any matter before the Committee (SO 3.14.1)

It is good practice for both Committee members and non-Committee members to declare any interests in items on the agenda.  They should withdraw from the room for discussion and voting on any of these items.

 


Nelson Regional Sewerage Business Unit

11 December 2015

 

 

Page No.

 

Apologies

1.       Confirmation of Order of Business

2.       Interests

2.1       Updates to the Interests Register

2.2       Identify any conflicts of interest in the agenda

3.       Confirmation of Minutes

3.1       18 September 2015                                                           5 - 8

Document number M1481

Recommendation

THAT the minutes of the meeting of the Nelson Regional Sewerage Business Unit, held on 18 September 2015, be confirmed as a true and correct record.    

4.       General Manager's Report                                9 - 35

Document number R5189

Recommendation

THAT the report General Manager's Report (R5189) and its attachments Draft Business Plan 2016/17 (A1468715) and Status Report (A452094) be received;

AND THAT the Nelson Regional Sewerage Business Unit not implement the trial proposed by Bokashi Logic.

 

5.       NRSBU Review of Alternative Biosolids Disposal Options                                                           36 - 39

Document number R5197

Recommendation

THAT the report NRSBU Review of Alternative Biosolids Disposal Options  (R5197) and its attachment (A1468738) be received;

AND THAT the current biosolids disposal practice at Bell Island is economical.

 

6.       NRSBU Risk Profile - Impacts of Contributor Exit 40 - 42

Document number R5204

Recommendation

THAT the report NRSBU Risk Profile - Impacts of Contributor Exit (R5204) be received.

 

7.       NRSBU Bells Island Wastewater Treatment Plant; Review of Automated Process Control and Influent Load Monitoring                                             43 - 46

Document number R5208

Recommendation

THAT the report NRSBU Bells Island Wastewater Treatment Plant; Review of Automated Process Control and Influent Load Monitoring (R5208) be received;

AND THAT an S::can unit be procured from DCM Process Control and installed at a cost not exceeding $95,000.

 

8.       Audited Financial Statements                         47 - 65

Document number R5237

       

 

 

  


 

Minutes of a meeting of the Nelson Regional Sewerage Business Unit

Held in Ruma Mārama, Level 2A, Civic House, 110 Trafalgar Street, Nelson

On Friday 18 September 2015, commencing at 1.01pm

 

Present:               Councillor M Higgins (Tasman District Council), Councillor R Copeland (Nelson City Council), and Mr D Shaw

In Attendance:     M Hippolite (Iwi Representative),  C McIntyre (Industry Customers’ Representative), Nelson Regional Sewerage Business Unit General Manager (R Kirby), Senior Asset Engineer – Solid Waste (J Thiart), Management Accountant (A Bishop), and Administration Adviser (G Brown)

Apology:              Councillor D Dowler (Tasman District Council)

 

 

1.       Appointment of Chairperson

 

There was a discussion regarding appointing a Deputy Chairperson and having alternate councillors appointed by Tasman District Council and Nelson City Council should a councillor be unable to attend.

It was agreed that this would be considered at the start of the new triennium 2016-2019.

 

Resolved NRSBU/2015/008

THAT Councillor Higgins be appointed Chairperson of the Nelson Regional Sewerage Business Unit for the 2013-2016 triennium.

Copeland/Shaw                                                                               Carried

 

2.       Apology

Resolved NRSBU/2015/009

THAT an apology be received and accepted from Councillor Dowler.

Copeland/Shaw                                                                           Carried

 

3.       Confirmation of Order of Business

There was no change to the order of business.

4.       Interests

There were no updates to the Interests Register, and no other interests with items on the agenda were declared.

It was requested that the Nelson Regional Sewerage Business Unit (NRSBU) Interests Register be sent out to members for review.

5.       Memorandum of Understanding

In response to a question, NRSBU General Manager, Richard Kirby, advised that the majority of the changes to the Memorandum of Understanding were minor. He highlighted that the main change was quorum was now two which consisted of one representative from each Council.

6.       Confirmation of Minutes

6.1       19 June 2015

Document number M1293, agenda pages 11 - 15 refer.

The following changes were requested to the minutes:

-      Page 12, change ‘trail and peals’ to ‘trials and peaks’

-      Page 14, change ‘Instrument’ to ‘Instrumentation’.

Resolved NRSBU/2015/010

THAT the amended minutes of the meeting of the Nelson Regional Sewerage Business Unit, held on  19 June 2015, be confirmed as a true and correct record.

Shaw/Copeland                                                                           Carried

  

7.       General Manager's Report

Document number R4817, agenda pages 16 - 56 refer.

NRSBU General Manager, Richard Kirby, presented the report.

Mr Kirby advised that Alliance and Nelson Pine Industries (NPI) had queried readings which the trade waste charges were based on. He added that Mr Wilson had also raised questions relating to the difference between the final wash up calculation and the estimate provided earlier in the year.

It was discussed that the current charging formula transferred risk for the variable charges to the other main customers if any customer changed their operations. It was suggested that a commercial charging structure going forward could be considered. If this was considered then a review was required as to how this would affect the business unit.

There was a discussion that if any if the three industries pulled out, the cost of operating the sewerage plant would be significantly less as there may not be the need for the ATADs as urban waste would be handled differently and was a lower cost operation.

It was highlighted the NPI wash up invoice was $40,000 more than previously estimated even though NPI had invested in pre-treatment works.

Invoice calculations were discussed and it was advised that there were no major errors, only a minor error in relation to the allocation of costs. The main reason for the difference was the BOD and Suspended Solids treated for NPI in the last three months were higher than estimated and increased treatment costs as a percentage of total Operating and maintenance expenditure.

Mr Kirby advised he was meeting with industry next week and would discuss a costing formula with them. In response to a question, Mr Kirby said that a charging formula review could be conducted but that the formula was quite logical. He added that risks needed to be identified and then the formula modified.

It was discussed that changes would need to be conducted with industry agreement as it was a legal contract and industry could withdraw with six months notice.

In response to a question about whether processes were robust enough, Mr McIntyre commented on the variation in sampling results and that the sampling largely reflected his firms sampling. Mr Kirby advised that there was the opportunity to contract an independent person to audit Nelmac’s sampling to confirm processes were being followed.

It was suggested that a digital photograph of each sample would be beneficial.

In response to a question, Senior Asset Engineer – Solid Waste, Johan Thiart, advised that with regards to the odour concerns at Best Island it seemed to be an operational issue with fluid found in the basin and too much acid being added.

In response to a further question, Mr Thiart said geobags would still be used for dewatering but  he was reluctant to use them for biosolids but this was still under review. It was suggested that odour could be discharged underground using a treating bag with a canopy.

Mr Kirby highlighted that at the top of page 20 of the agenda the words ‘with be considered’ needed to be removed.

Mr Kirby also pointed out that the ‘Review of security required at all facilities’ should have a target date of March 2016.

The following changes were requested to the Annual Report 2014/2015:

-       Page 27, the Pump Station Overflows graph is missing one overflow from the 2014/15 statistics

-       Suggestion to add that there were no extreme weather events

-       Page 29, Bell Island 2014/15 not 2013/14

-       Page 30, 5.3 right hand column, change ‘will be’ to ‘were’ and ‘considerde’ to ‘considered’

-       Page 31, 5.6 note all communication with residents

-       Page 33, check ‘Biological Oxygen Demand kg/day’ graph statistics

-       Page 36, remove comment

Resolved NRSBU/2015/011

THAT the report General Manager's Report (R4817) and its attachments (A1422904, A1423020) be received;

AND THAT the amended Annual Report 2015/16 be adopted subject to any audit amendments.

Copeland/Higgins                                                                        Carried

       

Attendance: Councillor Copeland left the meeting at 2.36pm.

Mr Kirby discussed the status report items.

 

 

 

There being no further business the meeting ended at 2.41pm.

Confirmed as a correct record of proceedings:

 

 

                                                         Chairperson                                        Date


 

Nelson Regional Sewerage Business Unit

11 December 2015

 

 

REPORT R5189

General Manager's Report

     

 

1. Purpose of Report

1.1   To report on progress with the NRSBU operational activities over the last few months and outlining what is proposed over the next few months.

 

2.       Recommendation

THAT the report General Manager's Report (R5189) and its attachments Draft Business Plan 2016/17 (A1468715) and Status Report (A452094) be received;

AND THAT the Nelson Regional Sewerage Business Unit not implement the trial proposed by Bokashi Logic.

 

 

 

3. Correspondence Received

Proposed Environmental Solution for Wastewater Treatment

3.1   The NRSBU has received an offer from a company called Bokashi Logic to undertake a trial using effective micro-organism (EM) technology to improve treatment efficiency at the NRSBU Bells Island wastewater treatment plant. 

3.2   Bokashi Logic has offered to run this trial at a cost of $54,570 to the NRSBU.  The company wants to demonstrate the efficacy of improving the sludge treatment capacity of the facultative ponds through the application of an additive (EM technology) to the ponds.

3.3   The trial requires the isolation of one of the three facultative ponds at Bell Island for a period of six months.

3.4   Should the trial prove effective then it is estimated that the on-going annual cost to the NRSBU would be around $200,000. This has been calculated based on information received from Bokashi Logic.

3.5   The saving that this EM Technology could accrue in operational costs is likely to be around $110,000 per annum.  This has been determined based on the annualised net present value of desludging the ponds every twenty years at a 5.5% discount interest rate.

3.6   Scientific research has shown that healthy facultative ponds are supported by micro-organisms more varied and prolific than what can be added using this technology. It becomes apparent from research that the additive will have a positive effect on biologic systems where there is a deficiency in micro-organisms.

3.7   This technology was used at Bell Island in the past to try and overcome odour issues with no demonstrable improvements.

3.8   Based on the information received, it is considered that there is no cost-effective advantage in implementing the trial.

Greenacres Golf Club

3.9   A letter was received from the Greenacres Golf Club notifying the Board that they are interested in using wastewater treated from Bell Island in future.

3.10 The Golf Club was informed that there is no intention to reticulate water from Bell Island in the current Business Plan and that the Board could investigate the viability of reticulating recycled water and consider this for inclusion into the Council’s 2018-28 Long- term Plans.  

4. Recent Actions

Accidental Discharge Consent Application

4.1   The application was lodged and returned on 23 July 2015 as it was considered to be incomplete. Additional work has been compiled and put into the amended application. The amended application will be ready for review in December 2015. 

4.2   Once the amended application is received by the NRSBU it will be reviewed by a lawyer specialising in Resource Management activities. (A proposal from Duncan Cotterill to review the application to the value of $2,000 plus disbursements has been accepted).

4.3   When the review has been completed the application will be lodged again.

          Contract 3458 – Nelmac; Operation and Maintenance

4.4   The reticulation and treatment operations have continued as normal over the last few months.

4.5   Load has been diverted away from the aeration basin for the last three weeks to optimise the use of treatment capacity of the plant.  This is expected to generate power savings and a decrease in biosolids production. It is expected that this process change is likely to be maintained through to April 2016.

4.6   New duty pumps have been installed at Airport and Saxton respectively during November 2015. Duty pumps at Saxton, Airport (one of 2) and Beach Road are now all fitted with N type impellors and it is anticipated that this will improve efficiency at all three these pump stations.

Contract 3619 – Biosolids Operation

4.7   The monthly average volume of biosolids sprayed is tracking the budgeted amount.

4.8   With changes to the loading of the plant process units, as explained above, it is expected that the volume of biosolids produced will decrease.

5.       Key Performance Indicators

5.1   The outcomes of key performance indicators for the 3 months to
31 October 2015 are outlined as follows:

5.2  


 

6.       Compliance Outcomes

6.1   The compliance outcomes for the 12 months to 31 October 2015 are outlined in the following table:

i)

Resource Consent Compliance (rolling 12 month record)

 

Ø Discharge to Estuary Permit

Not achieved. Two discharges of raw sewage occurred at Saxton pump station during this period.

 

Ø Discharge to Air Permit

100% Compliance

 

Ø Biosolids Disposal

100% Compliance

 

Ø Discharge treated 

waste water to land

100% Compliance

ii)

Odour Notifications

 

Ø Past three months

Nil.

 

Ø Last 12 months

Nil.

iii)

Overflows

 

Ø Past three months

Nil

 

Ø Last 12 months

Two.

iv)

Speed of response for maintenance works

 

In past three months:

Ø Three call outs for Saxton pump station. Blockage of duty pump.

Ø One call out related to Songer pump station.

 

Ø Response within 30 minutes.  Achieved.

 

7.       Review of Action Plan Implementation –
2014 Asset Management Plan and 2015/16 Business Plan

The following table indicates the draft time lines for the individual action items:

IP

Business Plan Action

Target Date

Completion Date

Comments

1

Review manuals annually.

March 2016

 

 

2

Consolidate all natural disaster information and review 3 yearly.

March 2016

 

 

3

 

Internal benchmarking carried out annually.

June 2016

 

 

4

Review risk of contributors leaving NRSBU.

June 2016

 

 

5

Review capacity of treatment components.

June 2016

 

 

6

Programme for pipe inspections.

June 2016

 

 

7

Annual review of contractor performance.

Dec 2016

 

 

 

8

Screen upgrade.

June 2016

 

 

9

Review secondary sludge separation.

Dec 2016

 

 

10

Construction second sludge storage tank.

June 2016

 

 

11

Develop sludge removal programme.

June 2016

 

 

12

Review effluent discharge management.

Mar 2016

 

 

13

Renewal of effluent discharge permit

Dec 2018

 

 

AP

AMP Action

Target Date

Completion Date

Comments

1

Annual customer survey.

Mar 2016

 

 

2

Business Continuity Plan review.

Jun 2016

 

 

3

Consider benefits of succession planning and how it might be implemented with be considered once governance issues (TDC and NCC) have been resolved.

Jun 2016

 

 

4

Review of security required at all facilities.

Mar 2016

 

 

5

Monitor sludge levels in ponds and ascertain long term removal and disposal requirements.

Mar 2016

 

 

6

Improve reporting requirements for asset condition, performance and maintenance from maintenance contractor.

Mar 2016

 

 

7

Implementation of internal bench marking (using historical data) of NRSBU network, pump stations, treatment and disposal facilities.

June 2016

 

 

8

Develop Demand Management Policy.

June 2016

 

 

 

8.       Health and Safety

8.1   There have been 2 Health and Safety inductions and 164 visitors to the Bell Island site over the past three months.

8.2   Only one Health and Safety incident was raised during the three month period. As a consequence procedures have been put in place to strengthen the wind stays on the door to the milliscreen.

9.       Financial

9.1   Power usage at the treatment plant is tracking well under budget. It is expected that this will continue through to April 2016. This is contingent on pond condition as well as other wastewater process units.

9.2   Following the replacement of the duty pumps with the spare duty pumps at the Saxton and Airport pump stations, the efficiency of the pump stations has returned back to long term trends.

10.     Business Plan 2016/17

10.1 The Business Plan 2016/17 is appended for the consideration of the Board.

 

Richard Kirby

NRSBU General Manager

Attachments

Attachment 1:    NRSBU Status Report December 2015  

Attachment 2:    NRSBU Draft Business Plan 2016-17  

   




 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 

Nelson Regional Sewerage Business Unit

11 December 2015

 

 

REPORT R5197

NRSBU Review of Alternative Biosolids Disposal Options

     

 

1.       Purpose of Report

1.1       To review the biosolids disposal options available to the NRSBU in the event that Rabbit Island is no longer available for this purpose.

 

2.       Recommendation

THAT the report NRSBU Review of Alternative Biosolids Disposal Options  (R5197) and its attachment (A1468738) be received;

AND THAT the current biosolids disposal practice at Bell Island is economical.

 

 

 

3.       Background

3.1       The Board has requested a short report that will quantify the benefits of biosolids application at Rabbit Island to the owners of Rabbit Island.

3.2       It is considered appropriate to understand the implications of the loss of opportunity to dispose of biosolids at Rabbit Island.

3.3       The improved productivity of the land resulting from biosolids spraying does not form part of this report, however it should be noted as being a benefit. (Extract from SCION report Attachment 1)

4.       Rabbit Island – Biosolids Disposal

4.1       In the event that Rabbit Island becomes unavailable for biosolids disposal the NRSBU will have to consider other disposal options.

4.2       Appropriate alternative biosolids sites for bioslids disposal are limited.

4.3       The alternatives listed in the table in Clause 5.0 will have to be investigated. This will require matching sludge treatment processes at Bell Island with the most appropriate disposal option.

5.       Comparison of seven biosolids disposal systems

5.1       As part of the exercise input was obtained from OPUS (John Crawford), MWH (Rainer Hoffman – capacity as wastewater specialist to NELMAC) and ADI (Nathan Clark – capacity as the process designer of all the major upgrades at Bell Island since 1998).

5.2       OPUS was commissioned to research the cost of treatment plants across New Zealand to establish a high level Net Present Value comparison for different modes of biosolids disposal. The NPV outcomes from this research is summarised in the following table;

5.3       This table shows that the Bell Island disposal option (currently sprayed at Rabbit Island) is the most cost effective.  The next most cost-effective is dewatering and applying the biosolids to a vermiculture composting operation.

5.4       The environmental benefits of disposing of biosolids on Rabbit Island cannot be underestimated. It is not only cost-effective but it also has a low carbon footprint. The alternative disposal processes are likely to have significantly larger carbon footprints.

6.       Implementing Alternatives

6.1       The additional costs, economic as well as environmental, associated with the implementation of an alternative biosolids disposal system at Bell Island could be significant.

6.2       The provision of additional facultative pond capacity at Bells Island could be an alternative. It could be brought on line through the construction of another pond or by increasing the capacity of the current ponds to digest sludge through installation of additional aeration capacity.

6.3       Additional pond capacity would also improve the resilience of the treatment facilities at Bell Island, increase capacity and improve quality of treated wastewater.

6.4       The integration of another pond will also provide further opportunity to divert load away from the activated sludge process that can create savings in terms of the use of electricity and use of chemicals at Bell Island.

6.5       ADI reported that the facultative pond option would assist in the management of biosolids through diverting solids from the biosolids system, and improve the breakdown of solids at medium capital cost, and at low operational cost.

7.       Biosolids Dewatering

7.1       Input received from MWH shows that it is feasible to develop a solar drying facility for the dewatering of biosolids at Bell Island. It is reported that dryness of between 70% and 80% is achievable.

What can the biosolids be used for

7.2       The concentration of heavy metals in biosolids produced at Bell Island limit the use of the biosolids.  The following table compares the typical biosolids produced at Bells Island with the New Zealand Guidelines;

7.3       The Bell Island biosolids is classified as Grade Ab and therefore has a restricted use requiring specific consents for discharge.

7.4       There is potential to reuse the biosolids produced at Bell Island through modification. Co-composting of biosolids and other organic material such as timber waste products has the potential to improve the quality of the biosolids produced to Grade Aa and will allow the use of the biosolids as an organic fertiliser. 

8.       Conclusion

8.1       The Bell Island biosolids disposal system is the most cost-effective alternative and with its low carbon footprint, should be retained by the NRSBU as the preferred disposal alternative.

8.2       That the NRSBU work with the Tasman District Council to retain all or as much area as possible of Rabbit Island for the purpose of spraying biosolids. 

 

Richard Kirby

NRSBU General Manager

Attachments

Attachment 1:    SCION economic analysis of Beneficial use of biosolids at Rabbit Island  

   



 

Nelson Regional Sewerage Business Unit

11 December 2015

 

 

REPORT R5204

NRSBU Risk Profile - Impacts of Contributor Exit

     

 

1.       Purpose of Report

1.1       To consider the risk to the Owners, NRSBU and Contributors if a contributor exits the Trade Waste Agreement.

 

2.       Recommendation

THAT the report NRSBU Risk Profile - Impacts of Contributor Exit (R5204) be received.

 

 

 

3.       Background

3.1       The impact arising from a contributor exiting its Trade Waste Agreement has been listed as a business risk in the current Asset Management Plan.

3.2       While the risk of a contributor going out of business is considered to be low it has become apparent that contributors are actively looking at modifying their discharge flows and/or loads to decrease their trade waste levies.

3.3      Contributors have indicated that their companies are price sensitive and that strategic investment decisions are being affected by the trade waste levies currently levied by the NRSBU.

4.       Discussion

Affect on stakeholders if one contributor exists the trade waste agreement

4.1       Currently should a contributor exit their trade waste agreement with the NRSBU their capacity allocation would revert back to the NRSBU. It would then be available for other contributors to purchase.

4.2       If none of the current contributors want to purchase increased capacity then the surplus capacity will become the responsibility of the two Council owners of the NRSBU.

4.3       The operation and maintenance cost will be then shared by the remaining contributors. The following table outlines the impact on the fixed costs (capacity related) and the consequential allocation of operating costs to the other contributors should a contributor exit their trade waste agreement;

Increased wastewater treatment capacity

4.4       Where any industrial contributor exits the agreement there should be a change in load to the wastewater treatment plant. Dry weather flows into the plant would reduce moderately, however the loads could reduce more significantly.  This could increase available treatment capacity at Bell Island.

4.5       The changes in loads to the plant will provide a range of opportunities to the NRSBU to decrease costs to the remaining contributors or to improve environmental outcomes.  The following table shows the potential decrease in loading should contributor C cease as a contributor;

4.6       The decrease in load resulting from an exit by industrial contributor C could generate savings on power usage at the treatment plant (Estimated 30% = $174,000 per annum) and the spraying of biosolids at Rabbit Island. (Estimated = $60,000 per annum)

4.7       The decrease in direct operational costs resulting from the exit of one of the industrial contributors will have a minor effect on the cost to the remaining contributors.

4.8       Should a contributor exit their trade waste agreement, thereby releasing capacity, then additional capital investment to increase capacity could be deferred beyond 2025. 

Other Mitigation Measures

4.9       Optimised replacement could result in a decrease in annual depreciation which would reduce trade waste levies to contributors.

4.10     Decreased sludge harvesting resulting from the exit of an industrial contributor could allow for the removal of:

·            One of the three ATAD trains,

·            The heat exchanger from the renewal programme.

5.       Conclusion

5.1       Although the exit of one of the industrial contributors from their trade waste agreement will have an impact, it is considered that it will not have a dramatic impact on trade waste levies to the remaining contributors and the NRSBU owners.

 

Richard Kirby

NRSBU General Manager

Attachments

Nil


 

Nelson Regional Sewerage Business Unit

11 December 2015

 

 

REPORT R5208

NRSBU Bells Island Wastewater Treatment Plant; Review of Automated Process Control and Influent Load Monitoring

     

 

1.       Purpose of Report

1.1   To review the need for automated process control and improved influent load monitoring at the Bell Island Wastewater Treatment Plant.

 

2.       Recommendation

THAT the report NRSBU Bells Island Wastewater Treatment Plant; Review of Automated Process Control and Influent Load Monitoring (R5208) be received;

AND THAT an S::can unit be procured from DCM Process Control and installed at a cost not exceeding $95,000.

 

 

 

3.       Background

3.1   The NRSBU Business Plan 2015/16 includes an ‘automation of process monitoring’ project with a budget of $110,000 within the upgrades funding of $1,235,000. 

3.2   It was intended that this project consider not only automated process control, but also improved load monitoring and the identification of extraordinary waste streams.

3.3   When this upgrade was considered by the NRSBU it was advised that a business case would be developed based on the outcome of automated load monitoring assessment.  It was proposed that this assessment be carried out under the NELMAC contract in developing the model for the treatment plant processes.

4.       Automated Load Monitoring Assessment

4.1   Due to difficulties in assimilating sufficient information on the various influent parameters and the consequential treatment processes, it has been decided that an automated load monitoring assessment would have sufficient uncertainty rendering it not cost-effective.  Instead a static model has been developed based on existing influent load monitoring information.

5.       Current load monitoring

5.1   The influent constituents to Bell Island are monitored based on daily flow proportional sampling.  The daily samples are analysed for COD and suspended solids by NELMAC in the Bell Island laboratory.

5.2   Once a week the samples are analysed for TBOD5, COD and Total Suspended Solids (TSS) at a registered laboratory.

5.3   Once a month inlet samples are analysed for Total Nitrogen and Total Phosphorous at a registered laboratory.

5.4   Samples are also programmed to be taken daily at the contributor points of discharge and kept for one week in a deep freeze at Bell Island to allow for testing for toxins should issues be observed at the treatment plant.

5.5   Each month four consecutive daily samples taken from the contributor points of discharge are randomly selected to determine the trade waste levies for that contributor for that month.

5.6   Recently there have been questions raised by contributors regarding the veracity of sampling results at their points of discharge.

5.7   Correspondingly loading spikes have been observed during spot sampling of the influent at the Bell Island Wastewater Treatment Plant. 

5.8   With these uncertainties, it is necessary that a more rigorous monitoring regime be implemented to restore confidence.  It is therefore proposed that improved monitoring of influent loads to the Bell Island WWTP be implemented that will identify extraordinary loads, shock loads and to provide more certainty to the sampling results at the contributors’ points of discharge.

6.       Automated Load Monitoring Proposal

6.1   The original intention was to purchase equipment to provide automated process control, as well as improved load monitoring and the identification of extraordinary waste streams.  At this stage it is not intended that the NRSBU progress with automated process control but instead implement automated continuous load monitoring. 

6.2   Automated load monitoring will help provide more accurate and timely information on load composition which will deal with the uncertainties outlined in clause 5.  In addition influent load concentrations will be available for analysis at 2 minute intervals for all the parameters currently tested for at monthly intervals.

6.3   The automated load monitoring equipment will gather information that can then be used to:

·            Constantly calibrate the static model of the wastewater treatment process;

·            Improve the understanding of waste composition that will be useful in developing future demand management strategies;

·            Assist in identifying sources of spike loadings and extraordinary waste components;

·            Improve the management and operation of the treatment plant.

6.4   It is therefore proposed that the equipment needed to undertake this task be procured with the funding allowed for in the Business Plan 2015/16.  The equipment proposed is a spectrometer.

7.       Automated Load Monitoring Equipment - Spectrometer

7.1   The spectrometer (S::can) has been developed by DCM Process Control.  It provides robust analysis, requires low maintenance and has the mobility to be transported around the wastewater network in addition to being based at the wastewater treatment plant.

7.2   The S::can has been developed as a modular unit and can be upgraded to record additional wastewater parameters if required.  It provides real time data on the concentrations of standard wastewater parameters.

7.3   The S::can will be able to;

·            Identify shock loading trade waste discharges that could disrupt the treatment process at the treatment plant.  Trade waste contributors have distinct spectral markers so the data gathered could identify the source of any shock loads and extraordinary loads;

·            Provide data that can be used to calibrate the wastewater treatment plant model and to simulate plant processes more accurately;

·            Identify trade waste discharges that should be controlled and allow the NRSBU to target source reduction through the Councils’ Trade Waste Bylaws;

·            Take samples where extraordinary loads are monitored.  The S::can can activate alarms so that the operators can process the samples in a prompt and timely manner.

7.4   The NELMAC wastewater specialist has also endorsed the use of this equipment. 

7.5   Watercare Ltd has advised that it uses several of these S::can units at their treatment plant and have found them particularly useful for monitoring trade waste discharges and process control of specific wastewater process units within the treatment plants.  Watercare Ltd also reported that the units are low maintenance and reliable.

7.6   At this stage the NRSBU is proposing to only install a “spetro::lyser” module in the S::can unit.  Once the operators are comfortable using the information from it and if it is warranted, the NRSBU could consider implementing the “ammo::lyser III pro” module in the S::scan unit. 

7.7   The information from the S::can unit will be available on a webserver and available for analysis by operators, the wastewater specialist and NRSBU officers.

8.       Spectrometer Procurement Details

8.1   The S::can unit costs $86,961.73 (plus GST) to purchase.  This includes installation, training, 12 months analytical support and 12 month modem fee.  This cost is subject to exchange rate fluctuations.

8.2   The cost of connecting the system to SCADA network is estimated at $2,500 (plus GST).

8.3   The installation of the unit would reduce and maybe eliminate the need to collect and freeze daily samples of influent.  This would potentially accrue of up to $65,000 annually in operational costs.  This saving alone proves a valid business case and in addition the benefit of more certainty in other sampling results.

9.       Conclusion

9.1   The procurement of an S::can unit will improve the operational management of the NRSBU activities.  It will assist with the identification and management of trade waste discharges and provide reliable information to improve the treatment plant modelling capacity and potentially save a significant amount on operational costs.

9.2   The S::can unit will improve the ability of the NRSBU to identify extraordinary waste discharges and allow for the identification of trade waste customers by the two Councils that need to be managed through trade waste bylaws. 

 

Richard Kirby

NRSBU General Manager

Attachments

Nil


 

 

 

Nelson Regional Sewerage Business Unit

11 December 2015

 

 

REPORT R5237

Audited Financial Statements

     

 

Attached for information is the Audit letter and approved financial statements for the year ending 30 June 2015.

 

 

Shailey McLean

Administration Adviser

Attachments

Attachment 1:    A1470592 - Nelson Regional Sewerage Business Unit Auditors Report 30 June 2015  

Attachment 2:    A1470596 - Nelson Regional Sewerage Business Unit Signed Financial Statements 30 June 2015