Report Spicer Landfill Odour Report - Porirua City · Steve Hutchinson (MWH Consultant) Jeremy McKibbin (WWLL Process Engineer) Mike Binns (WWLL WWTP Supervisor) Discussion on processing

Report

Spicer Landfill Odour Report

Prepared for Porirua City Council (PCC) “the Client”

Prepared by Beca Ltd (Beca)

6 December 2015

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Beca // 6 December 2015 3030300 // NZ1-11749702-8 0.8 // i

Revision History Revision Nº Prepared By Description Date

1.0 Mark Christison Final Report for Release 6 December 2015

Document Acceptance Action Name Signed Date

Prepared by Mark Christison

6 December 2015

Reviewed by Humphrey Archer

6 December 2015

Approved by Sam Fielden

6 December 2015

on behalf of Beca Ltd

© Beca 2015 (unless Beca has expressly agreed otherwise with the Client in writing).

This report has been prepared by Beca on the specific instructions of our Client. It is solely for our Client’s use for the purpose for which it is intended in accordance with the agreed scope of work. Any use or reliance by any person contrary to the above, to which Beca has not given its prior written consent, is at that person's own risk.

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Beca // 6 December 2015 3030300 // NZ1-11749702-8 0.8 // ii

Executive Summary Porirua City Council (PCC) and Wellington City Council (WCC) jointly own and operate the Spicer Landfill in Porirua. PCC has received on-going complaints about odorous emissions from the Spicer Landfill over the last eighteen months that are well above the previous level of such complaints from surrounding residents and businesses. The issues have escalated to the point where Greater Wellington Regional Council (GWRC) issued an abatement notice to PCC on 17 June 2015 associated with odour emissions from the landfill.

PCC engaged Beca to undertake an operations review of Spicer Landfill. The aim of the review being:

a. Review the Waste Acceptance Criteria (WAC) to ascertain whether any accepted waste streams are specifically contributing to odour issues.

b. Interview EnviroWaste staff managing and operating the landfill and visit the landfill to witness typical daily operations particularly around the handling of the Porirua WWTP biosolids.

c. Review of odour complaints over the last 5 years and noting any significant operational changes that have occurred over this time frame.

d. Interview the Resource Consent Compliance Officer from Wellington Regional Council (WRC) to understand their perspective on issues.

e. Look at possible odour monitoring technology that can objectively measure and report likely odour nuisance to assist in landfill management.

f. Identify any short term contractual variations which could improve odour control

In conducting this review, Beca has not seen any evidence that waste is being delivered to the Spicer Landfill that does not conform to the WAC and therefore the Resource Consent for the site. Further analysis of odour events and biosolids dryness ratio, shows there is no correlation between these two sets of data (i.e. when the biosolids dry solids content is low there is no corresponding increase in odour complaints). There are a number of factors in operating the current site that make it more difficult, or more cumbersome for the Contractor to ensure odour issues are not created at the site boundary. These factors are:

a. Biosolids from the Porirua Wastewater Treatment Plant (WWTP) - a low dry solids content (12-14%), makes blending and handling of the material with general refuse difficult at the site. The Porirua WWTP is also paying more in transport and disposal costs than is necessary than if biosolids were produced with a dry solids content above 18%.

b. Price increases at the Spicer landfill are almost certainly responsible for a drop in commercial tonnage to the landfill since July 2013. PCC should consider reviewing its pricing strategy to remain competitive with the two other Landfills in the Greater Wellington region. This will likely increase tonnage at the gate and make more material available for blending with the biosolids.

There are a number of initiatives that should be relatively easy to implement. These should reduce the likelihood of occurrence of odour events at the Spicer Landfill. Key amongst these recommendations are:

a. PCC makes the Contractor responsible for maintaining a minimum stockpile of suitable cleanfill at the site at all times.

b. PCC works with Wellington Water Limited (WWL) to agree some measures around the delivery and dry solids content of WWTP biosolids delivered to Spicer landfill. It is recommended that the Waste Acceptance Criteria (WAC) remain unchanged.

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c. PCC works with its advisors and contractors to ensure the next series of Resource Consent reporting is fully compliant with consent conditions. This should be a key result area.

d. PCC, its advisors and the Contractor review the current Spicer Landfill Risk Register (see Appendix 1) and update with the learnings from the current odour complaints and issues around gas emissions.

e. PCC evaluates the cost benefit of installing real time odour monitoring technology to assist with odour management of the site.

The full list of recommendations is documented Table 6 on page 16 of the report.

Beca would like to thank all the stakeholders contacted as part of this review. All parties were proactive and timely in supplying information for this report.

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Contents

1 Background 1 Assumptions, limitations and disclaimers 1

2 Contract Review Methodology 3

3 Spicer Landfill Operational Review 5 3.1 Roles and Responsibilities at Spicer Landfill. 5 3.2 Biosolids from Porirua WWTP 6 3.3 Issue of Reduction in General Refuse available to mix with WWTP Biosolids 9

4 AECOM Report and PCC Response 12

5 Operational Reporting 13 5.1 Reports Required 13 5.2 Consent Reporting 13 5.3 Risk Management Reporting 15

6 Operational Opportunities for Improvement 16

7 Odour Monitoring Technology 17

8 Recommendations 18

Appendices

Appendix A Porirua City Council Risk Assessment Tables for Spicer Landfill

Appendix B Real Time Odour Monitoring Technologies – Supplier Brochures

Appendix C Report Documentation Reference List

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1 Background

Porirua City Council (PCC) has received on-going complaints from surrounding residents and businesses about odorous emissions from the Spicer Landfill over the last eighteen months that are well above the previous level of such complaints. The issues have escalated to the point where Greater Wellington Regional Council (GWRC) has issued an abatement notice (A807/808) to the PCC.

Further, concerns have been raised by Envirowaste Services Limited (ESL), the contracted landfill operator, around the deposition of wastewater biosolids at the landfill and the effect this is having on landfill stability, gas extraction and site generated odours.

PCC has seen a decline in the tonnage of general waste to the landfill over the last 10 years and more specifically over the last 24 months. The recent reduction in tonnages appears to be related to a corresponding increase in gate charges for general refuse on 1 July 2013. This coupled with the disposal of the wastewater biosolids, is causing issues for the landfill operator with regards to the amount of daily cover required to successfully handle and dispose of the biosolids as they are delivered to site.

Beca was commissioned by PCC on 3 November 2015 to undertake a review for the odour issues at Spicer Landfill. The objectives of this contract review were to:

a. Review the Waste Acceptance Criteria (WAC) to ascertain whether any accepted waste streams are specifically contributing to odour issues.

b. Interview EnviroWaste staff managing and operating the landfill and visit the landfill to witness typical daily operations particularly around the handling of the Porirua WWTP biosolids.

c. Review of odour complaints over the last 5 years and noting any significant operational changes that have occurred over this time frame.

d. Interview the Resource Consent Compliance Officer from Wellington Regional Council (WRC) to understand their perspective on issues.

e. Look at possible odour monitoring technology that can objectively measure and report likely odour nuisance to assist in landfill management.

f. Identify any short term contractual variations which could improve odour control.

This report outlines the findings of the review and associated interviews with key stakeholders.

This odour review is not a design or environmental review of the performance of the Spicer Landfill nor a contract compliance audit of the contract between PCC and ESL, but rather a review of operational matters that maybe contributing to less than ideal odour control at the facility.

Beca has not reviewed, nor has any comment on the current Abatement Notice A807/A808 issued by GRWC dated 17 June 2015. Beca understands PCC is resolving this issue with GWRC directly.

Assumptions, limitations and disclaimers This report has been prepared by Beca on the specific instructions of PCC. It is solely for PCC’s use for the purpose for which it is intended in accordance with the agreed scope of work, and must be read in conjunction with, the assumptions, limitations and disclaimers set out below and elsewhere in the report. It

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should be read in its entirety, and no portion of it should be relied on without regard to the report as a whole and the methodologies and techniques adopted in its preparation as described in the report.

Any use or reliance by any person contrary to the above to which Beca has not given its prior written consent is at that person’s own risk.

The assessment provided in this report is based solely on the information detailed herein and is subject to the following limitations:

This assessment encompasses only those areas expressly included in the scope.

Beca has relied on information provided by PCC staff, and by other third parties, we have not sought to independently verify such information. To the extent any of the information provided is inaccurate or incomplete, the opinions expressed by Beca in this report may no longer be valid and should be reviewed.

While Beca has used all reasonable skills of a professional consultant in providing this report, which may include opinions and recommendations, Beca does not guarantee or otherwise warrant any particular outcome, and in particular Beca does not guarantee that following such recommendations will ensure full compliance with any laws or guidelines. Responsibility for the operational performance of the Spicer Landfill will continue to rest with the Contractor and PCC, and not Beca.

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2 Contract Review Methodology

In formulating this report Beca has interviewed key contract stakeholders and reviewed a number of key documents. Interviews with stakeholders were conducted as listed in Table 1.

Table 1 – List of key stakeholders interviewed as part of this report.

Date of Meeting

Location Key Stakeholder/s Basis of Discussions

3 November 2015

Spicer Landfill, Landfill Road, Porirua

Brendon Cribb (ESL Spicer Landfill Manager)

Paul Mullinger (ESL National Landfill Manger)

Discussion around operational issues and the current contract. Discussion on how things could work better to reduce odour.

3 November 2015

Porirua WWTP, Porirua

Gary O’Meara (WWLL Chief Operating Officer)

Steve Hutchinson (MWH Consultant)

Jeremy McKibbin (WWLL Process Engineer)

Mike Binns (WWLL WWTP Supervisor)

Discussion on processing of WWTP biosolids, process improvements underway and issues caused at landfill

4 November 2015

PCC Civic Offices Peter Keller (PCC Solid waste Manager)

Engineers Representative.

General discussion on the contract, issues being experienced and some history on the landfill.

4 November 2015

Tonkin and Taylor Offices, Wellington.

Hugh Cherrill (Tonkin and Taylor Consultant)

Engineers Assistant

General discussion on contract management and T&T role in the contract.

4 November 2015

WCC Civic Offices, Wellington

Anthony Wilson (WCC Chief Asset Officer)

Adrian Mitchell (WCC Manager Waste Operations)

Discussion on Landfilling and impact of biosolids

5 November 2015

Southern Landfill, Landfill Road, Brooklyn

Adrian Mitchell (WCC Manager Waste Operations)

Southern Landfill Site Manager

WCC experience with landfilling biosolids at their Southern Landfill site

9 November 2015

GWRC Civic Offices, Wellington

Louise McKenzie (GWRC Consent Compliance Officer)

Kirsty van Reenen (Resource Advisor, Environmental Regulation, GWRC)

Jeremy Rusbatch (Team Leader Consent and Compliance, GWRC).

Kyle Christensen (Water and environment Leader, Cardno Consultants).

Spicer Landfill resource consent compliance issues, resource consent reporting and consent reviews.

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Beca has reviewed a number of reports and operational manuals. A list of these is included at Appendix 3. The review of these documents was undertaken to provide Beca with an appreciation of some of the issues currently being experienced at the landfill, who is responsible for the management of these issues, and to look for opportunities for improvement with the aim of reducing odour nuisance from the Spicer Landfill site.

Some of the data made available to Beca has been summarised from various reports in this report. This is for illustrative purposes only and is not intended to portray the entire history of events at the landfill.

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3 Spicer Landfill Operational Review

ESL operates and maintains the Spicer Landfill under a contract to PCC. The contract commenced on 1 October 2011. ESL has operated the landfill on a continuous basis since the contract start date.

3.1 Roles and Responsibilities at Spicer Landfill. Key roles and responsibilities for the current operations and associated odour issues attributed to the landfill site are detailed in Table 2 below. This list is not all encompassing but items below have been identified specifically, as these issues have been raised in interviews with the stakeholders as possible reasons for increased odour from Spicer Landfill.

Table 2 – Responsibility for Issues Raised in Stakeholder Interviews.

Issue Party Responsible under Contract

Commentary

Biosolids from Porirua WWTP are causing a lot of odour issues

ESL. ESL is responsible for meeting consent conditions under the contract subject to WWTP biosolids meeting the Waste Acceptance Criteria (WAC). Based on the data received from WWL, the biosolids (over the last 22 months) have been above 11% DS and are therefore compliant.

Supplying compliant biosolids to Spicer Landfill

WWL (WWL) as operator of Porirua WWTP

According to the Landfill consent, WWL is supplying compliant biosolids. WWL is currently endeavouring to increase the dry solids content as this reduces cartage costs but is also beneficial to the landfill operator as it reduces the total amount of mixing material needed for the same weight of biosolids.

Do not have enough general refuse and other products to get good mixing ratio with incoming biosolids

ESL.

Indirectly PCC through pricing policy.

Minimum mixing ratio under the consent is 5 parts suitable material to 1 part biosolids by weight (with biosolids >11% DS). Figures 5 and 6 illustrate that this ratio has been achieved over a considerable period. Whilst there were 5 months in 2014/2015 year when there was insufficient general refuse to meet this blend ratio alone the addition of daily cover and green waste provided sufficient material to meet the blend ratios in the consent. PCC have reported this in their annual compliance report. In the 2013/14 GWRC consent report there was no commentary around this method of determining the blend ratio. The increase in landfill charges by PCC in July 2013 has probably affected the volume of general refuse coming to the landfill from commercial operators. See figure 8 later in this report.

No ability to decline odorous loads

ESL It could be argued that the WAC set the quality of material able to be deposited in Spicer Landfill. No data was viewed that suggested materials non-compliant with the Landfill WAC have been received at the landfill. ESL’s complaint about not being able to reject odorous loads is hard to understand where the load complies

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Issue Party Responsible under Contract

Commentary

with WAC. Landfills by their nature accept odorous materials. It is how this material is handled, how quickly it is handled and disposed of in the landfill which is key to whether odour will be prominent on the site or not.

PCC Spicer Landfill gate charges are making issues worse for the Contractor as the volume of general refuse from commercial customers has reduced (thought to be going to other landfills).

PCC set landfill gate charges Figures 5 and 6 show that minimum contract blending ratios of 5:1 have been maintained throughout the contract period, although daily cover materials have been needed for 5 months in 2014/15 to achieve the required blend ratios.

PCC has a range of other issues to consider in setting gate prices at Spicer Landfill, including how competitor landfills are pricing and the Council strategy and objectives around diversion of materials from landfill. Landfill gate charges should be set to meet the multiple objectives. PCC should consider whether it can afford to lead waste diversion initiatives or follow other Councils pricing signals. This will impact PCC’s landfill gate price setting policy.

Lowering the current gate charge for general refuse for commercial customers will almost certainly increase volumes received if the new rate is competitive with the other two Region’s landfills.

Gas leakage from the landfill

ESL ESL rely on the landfill gas system to be designed so that if it is well operated and maintained, methane levels as measured on the surface are less than 5000ppm. Since 2014 there are documented recordings of methane levels, at spot locations on the landfill surface, being well above this number. It is claimed this is due to insufficient wells, but minutes of contract meetings and the AECOM report, also show areas of poor maintenance have led to these problems. Many of these defects have been reported to have been repaired but it is understood some are still to be resolved by ESL.

The Contractor has an obligation to recommend any extensions to the Landfill Gas extraction system (wells or extension to wells) in a timely manner as referenced in their Landfill Management Contract with PCC.

3.2 Biosolids from Porirua WWTP The Porirua WWTP sends dewatered sludge to Spicer Landfill seven days per week during landfill operating hours. It was recently agreed between the WWTP and ESL that the last bin will arrive no later than 3pm on each day to provide the landfill operators sufficient time to mix and cover the biosolids and apply daily cover.

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Typically the WWTP has supplied 6 x five tonne bins per day Monday to Friday and 3 bins on Saturday morning.

WWL have recently changed polymers used in the dewatering process and this has increased the sludge dryness from an average of 12-14% to between 18% and 20%. WWL believe this will reduce the volume of bins to 5 per day Monday to Friday and 3 on Saturday. WWL have indicated that they wish to trial reverting to the dry powder polymers once the current plant modifications are completed as the new liquid polymer is more expensive. It is recommended that the holistic costs to the shareholders in running both of these facilities be taken into account before any changes are made that may reduce the current centrifuging efficiency which is delivering biosolids around 18% to 20% DS.

Figure 1 – Graph of WWTP Centrifuge Performance and Biosolids Dryness 1 Jan 2014 to 31 Oct 2015 (data source WWL biosolids testing from Porirua WWTP)

The efficient operation of the centrifuges at the Porirua WWTP is critical to efficient WWTP operations (less biosolids to transport and optimal polymer and power consumption at WWTP) and assists the Spicer Landfill operator through:

a. Producing a biosolids product that is easier to deal with – makes handling easier

b. Drier biosolids reduce the tonnage of general refuse required to meet the Resource Consent blend ratio of 1 part biosolids to 5 parts refuse or suitable equivalent.

It is not uncommon for landfills to accept biosolids from municipal wastewater treatment plants. The Porirua WWTP is an extended aeration plant, which means the biological compounds are well oxidised due to the plant having a sludge age between 17 and 27 days. Southern Landfill receives up to 16,000 tonnes of biosolids (at 28% dry solids, although it has been as low as 18%) per annum and successfully blends this material with municipal waste at a ratio of 1:4. The biosolids generated by both the Moa Point and Seaview Wastewater Plants in comparison to the Porirua WWTP biosolids are “fresh and reactive” with a sludge age of only 3-5 days. These biosolids are odorous but have been, and continue to be, successfully handled at the region’s other landfills.

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During site visits to Spicer Landfill and the Porirua WWTP, the biosolids observed on the day had an earthy but not overpowering smell. Both ESL and WWL staff acknowledged that the biosolids observed during the site visits (as shown in figures 2 and 3) were good in terms of their ability to handle them.

Figure 2 – Biosolids mixing pit at Spicer Landfill Figure 3 – Dewatered Biosolids loading at Porirua WWTP. Approximately 20% DS Biosolids in the photo.

Whilst it is appreciated that any storing of centrifuged biosolids from the Porirua WWTP can lead to a more odorous product, this is a common issue for all biosolids products from wastewater plants. It is also impractical to guarantee that there will not be occasions when biosolids inventory increases in the wastewater treatment plant. Beca analysed the dryness of the biosolids on any given day against the dates of odour complaints received by GWRC and there appears to be no correlation between the two sets of data (Figure 4).

Figure 4 – Odour Complaints received by GWRC plotted against Biosolids %DS delivered to Spicer Landfill 1 Jan 2014 to 31 Oct 2015 (data sources WWL biosolids data and GWRC complaints register).

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The draft Landfill Operations Management Plan Section 7.6 dated 28 August 2015, compiled by ESL, recognises that to prevent odours from affecting adjacent landowners, it is important to promptly cover refuse on a small, well maintained working face.

GWRC compliance staff indicated that they receive less than 12 odour complaints per annum from each of the other landfills in the Wellington Region. Discussion with Wellington City Council staff at Southern Landfill (where they also have to handle biosolids daily) confirmed the number of complaints.

Given the common ownership of both Spicer Landfill and Porirua WWTP, there would be a significant benefit for the owner in getting the Contractors’ objectives at each site aligned.

3.3 Issue of Reduction in General Refuse available to mix with WWTP Biosolids

The mixing ratio required under the Resource Consent for Spicer Landfill has not altered since ESL tendered for and won the contract in 2011. Whilst the tonnage of general refuse has reduced, the blending ratio has remained above the 5:1 ratio based on information supplied to Beca via the PCC generated SWM Reports.

In coming to this conclusion, Beca has reviewed PCC data from SWM reporting, and the GWRC consent compliance report comments associated with complying with Condition 38 of WGN 940046 [21367].

Figure 5 – Refuse:Biosolids Blend Ratio 2007 to 2014 (data source PCC SWM Reports)

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Refuse: Sludge (excl. Op. Matl.) Refuse: Sludge (incl. cleanfill) Refuse: Sludge (incl. all Op. Matl.)

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Figure 6 – Refuse: Biosolids Blend Ratio June 2014 to June 2015 (data source PCC SWM reports).

PCC controls the Spicer Landfill gate prices and at the time of the review, the gate prices for General Refuse in the region are shown in Table 3.

Table 3 – Regional Landfill Gate Prices for General Refuse at 31 October 2015

Landfill Landfill Owner Current General Refuse Charge inclusive of GST*

Variance to Competitor Landfill

Spicer Landfill PCC (78%)

Wellington City Council (22%)

$ 129.00 per tonne 6% higher/tonne than Southern Landfill

10.7% higher/tonne than Silverstream Landfill

Southern Landfill (Wellington Wellington City Council

$ 121.80 per tonne

Silverstream Landfill Hutt City Council $ 118.00 per tonne

* Rates as published on Council websites at 31 October 2011

The current differential in gate prices between the region’s landfills provides enough incentive for commercial operators to divert tonnages from Spicer Landfill. Figure 7 illustrates the impact of price increases across the region’s landfills as measured against the historical commercial tonnage received at Spicer Landfill. Whilst this data is based between 2002 and 2008, the same trends have been reflected recently in changes of relative pricing between the three landfills in the area. The reduction in commercial tonnage from Spicer Landfill since mid-2013 looks like it is attributable to a price rise at the gate on 1 July 2013.

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Refuse: Sludge (excl. Op. Matl.) Refuse: Sludge (incl. cleanfill) Refuse: Sludge (incl. all Op. Matl.)

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Figure 7 – Impact of landfill gate price on commercial tonnage received at Spicer Landfill July 2002 to September 2008 (Source PCC Spicer Landfill Asset Management Plan July 2014 Appendix 1)

The long term trend for total refuse deposited at Spicer Landfill is illustrated in Figure 8 below. Whilst the domestic tonnages received have remained reasonably consistent, there has been a marked reduction in general refuse since 1 July 2013.

Figure 8 - Long term trend for the disposal of refuse and biosolids at Spicer Landfill Jan 2010 to Oct 2015. (Source PCC SWM Reports 2014-15).

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PCC new gate charge

for general refuse 1 July

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4 AECOM Report and PCC Response

ESL commissioned AECOM Consulting Services to undertake an independent review on its behalf to evaluate some of the concerns ESL had expressed to PCC through contract meetings. AECOM produced a report on 19 August 2015 and a copy of this report was supplied to PCC and GWRC. Beca understands that PCC (and its Landfill Advisors) have responded to each of the issues raised in the report. This report is not a review of either of those commentaries, as many of the items are associated with landfill design and filling issues. The table below has extracted some of the operational issues from the report and Beca has reflected on those issues and has commented accordingly.

Table 3 – Contract Operations Issues raised in AECOM Report dated 19 August 2015.

AECOM Report Item/Commentary PCC and Advisor Response Beca Contract Review Comments

Clause 9.1 - Reference to USEPA guidelines for determining biosolids mixing ratios.

Discussion around application and intent of the standard. General disagreement with AECOM interpretation.

It should be noted the referenced document is a guideline only and is not referenced at all in the Consents for this site. The operational rules associated with mixing biosolids from the WWTP for Spicer Landfill are governed by the Resource Consent granted for the site (WGN 9400046 (01) [21367] condition 38. The consents are clear that a ratio by weight above 5:1 is compliant.

Clause 9.7 – commentary that biosolids received from WWTP are below best practice guidelines for this material at landfills. Discussion on the odorous and reactive nature of the biosolids and ability to turn odorous loads away.

Commentary from Peter Keller on the dewaterability of extended aeration biosolids.

PCC and advisors comment that “less wet sludge may result in more permeable waste and better gas collection. Improved dewatering is likely to reduce the amount of sludge by about one bin per day (i.e 5 bins instead of 6 bins). Drying or alternate treatment could reduce quantities further”.

The Contract and consent conditions are clear that biosolids above 11% DS from the WWTP are acceptable at the landfill. ESL was aware of this from the time of tendering and data presented has shown that they have effectively handled this material in the past.

WWL has recently taken over operations of the WWTP and is working to improve the dewatering process. WWL operators are endeavouring to consistently produce biosolids with a dry solids content above 18%.

Under the contract and terms of the consent, the biosolids from the Porirua WWTP are meeting the WAC.

Item 10 – Works done by ESL. List of work completed by ESL in the AECOM report is agreed by PCC and advisors.

All of the items listed appear to be core duties under the terms of the agreement.

Providing additional management resources to the site is a positive initiative by ESL.

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5 Operational Reporting

5.1 Reports Required

There are a variety of reports required by various Stakeholders as part of the operations of Spicer Landfill. The standard reports are listed in Table 4.

Table 4 – Standard Operational Reporting at Spicer Landfill.

Report Written By Distributed To Purpose

Quarterly Resource Consent Compliance Report

PCC GWRC To illustrate on-going compliance with consent. Increased level of monitoring by GWRC

Annual Resource Consent Compliance Report

PCC Reviewed and commented on by GWRC

To demonstrate compliance with the terms and conditions of the various consents WGN 940046 (1 to 4)

Joint Landfill Committee Report – normally 6 monthly

PCC Solid Waste Manager

Joint Landfill Committee Members

To keep joint committee advised on key issues at the landfill.

Community Liaison Group – every 12 months or as required.

PCC Solid Waste Manager

Community Liaison Group.

Update on landfill matters for key stakeholders identified under the consent. Opportunity for CLG to comment on Landfill Operations Management Plan before its annual submission to GWRC.

Contractors Report – monthly

ESL PCC Solid Waste Manager and Tonkin and Taylor.

Report on issues detailed under the contract and provide written record of performance.

5.2 Consent Reporting Resource Consent WGN 940046 contains two discharge permits and two water permits that govern how the consent holder shall demonstrate compliance with the Resource Consent granted for the on-going operation of Spicer Landfill. Table 5 illustrates the GWRC Compliance Officers assessment of PCC resource consent compliance associated with the four permits in place at Spicer Landfill, as reported in GWRC Annual Compliance Monitoring Reports.

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Table 5 – WGN 940046 Consent Compliance as reported by GWRC in their Annual Compliance Review reports.

Consent Consent Description

GWRC Compliance

Rating 2010/2011

GWRC Compliance

Rating 2011/2012

GWRC Compliance

Rating 2012/2013

GWRC Compliance

Rating 2013/2014

GWRC Compliance

Rating 2014/2015

WGN 940046 [1381]

To discharge landfill gas, odour and dust to air from Spicer Landfill.

Fully compliant

Environmental non-compliance

Fully complaint

Technical non-compliance

Currently under review

WGN 940046 [4964]

To divert and discharge storm water run-off from above and around the site of Spicer Landfill to Mitchell Stream

Significant non-compliance





WGN 940046 [5975]

To take water as leachate for disposal off site from Spicer landfill.

Fully Compliant

Technical non compliance

Fully compliant

Full compliant Currently under review

WGN 940046 [21367]

To discharge contaminants onto or into land for the purpose of landfilling wastes.



Fully compliant

Environmental non-compliance


GWRC define the above compliance terminology as follows: Fully compliant – all administrative conditions assessed are met. All effects based and best practice conditions assessed are met. Environmental non-compliance – Breach of effects based or best practice consent condition with minor actual or potential environmental effects. Breach of effects based or best practice consent condition with more than minor actual or potential environmental effects that can be fixed immediately. Works outside scope of consent issued where environmental effects not considered. Technical non-compliance - Failure to supply and/or keep adequate records. Failure to adequately notify GWRC of works. Minor works outside the scope of consent issued but within scope of environmental effects considered when consent processed. Significant non-compliance – Persistent Grade C breach of same condition and failure to respond to requests for compliance. Significant breach of effects based or best practice conditions that causes environmental effects ( e.g. unauthorised discharge from site to water, significant disturbance to sensitive receiving environment or site on a scale not envisaged by consent, significant breach of water quality/quantity limit). Significant works outside scope of the consent issued that causes environmental effects. GWRC commented in their interview that they would like to see more trending and data analysis performed on information presented to them in the annual compliance report for Spicer Landfill. GWRC would also like this analysis to come with recommendations to resolve any issues illustrated in the compliance reports. Condition 37 of WGN 940046 [21367] implies an obligation on the consent holder to do this. Given GWRC are currently reviewing consent conditions for this site it would be worth PCC establishing these processes now in anticipation of new consent conditions. Further these tools should enable a more proactive response to managing site odour and storm water issues. Owners and operators of such facilities would typically expect “fully compliant” annual assessments of their resource consenting reports.

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5.3 Risk Management Reporting Integral to the operational review has been a review of the risk registers associated with Spicer Landfill. The Solid Waste Manager advised that the risk register in the 2014 Spicer Landfill Asset Management plan holds the relevant register for the landfill operations. A copy of this risk register is contained at Appendix 1. A review of this register indicates there may be some risks which are missing and the plan appears to be lacking mitigation strategies to reduce and/or remove the noted risks. Given the experience gained through the recent issues, the current register should be thoroughly reviewed and updated. The following risks would be worthy of inclusion. There are likely to be other risks that should be added to the risk register over and above the items below.

a. Fire in the landfill – mitigation strategy should include a detailed response plan as these events. b. Extended odour emissions and breach of consent conditions. c. Elevated H2S recorded on the site. d. Elevated methane readings on the site (>5000 ppm) e. Blockage of subsurface storm water drains f. Failure of landfill cell liner. g. Breach of the leachate pond. h. Breach of the storm water pond.

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6 Operational Opportunities for Improvement

Beca suggests the following changes to existing operational management at Spicer Landfill that may reduce odourous emissions from the landfill. The table suggests a lead agency responsible for implementing the change.

Table 6 – Recommended changes to the current Landfill Operations.

Recommendation Suggested responsible Party

Discuss with WWL their ability to deliver sludge loads at more specific times and periodicities throughout the day. Currently the last load of sludge for each day is accepted at the landfill at 3pm.

PCC/WWL

Establish more formal communications between the landfill operator and the WWTP operators so that any special requirements (plant outages, unusual biosolids etc.) are advised to the landfill early. Likewise if the landfill is having specific issues that could affect their ability to accept biosolids, they should be talking to the WWTP. It is understood WWL has developed some draft formats to allow this to commence.

PCC/WWL

Consideration should be given to making the sourcing and maintenance of a suitable minimum stockpile of cover material, the sole responsibility of the landfill operator (resource consent condition17 of consent WGN 940046 [21367]) to ensure there is always suitable material available on site to provide daily cover and blending material for the incoming biosolids.

PCC and Advisors.

PCC should target 100% compliance in all consenting reports. PCC should consider formal quarterly meetings with GWRC and WWL to discuss consent issues associated with WWTP and Spicer Landfill. Meetings should be minuted with actions assigned with agreed completion dates.

PCC and Advisors/GWRC

PCC should consider its pricing policy at Spicer Landfill. A pricing point more in line with the competing local landfills may see volumes return to pre 1/7/2013 levels and thus make the handling of biosolids at the landfill easier.

PCC

Consideration should be given to establishing a daily electronic log on the site. This log could be available to the Engineers Rep via a web based solution, and could be used to record complaints, enquiries and general site activities including any unusual biosolids deliveries etc. The electronic log should be the Operators “bible” as to what has happened on the Landfill.

PCC and ESL

Some of the above recommendations may have an impact on the cost of service provided through the contract.

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7 Odour Monitoring Technology

Recent advances in odour sensing technology has seen the emergence of permanently installed odour monitoring stations at facilities that have the potential to produce objectionable or offensive odours and disrupt neighbouring business and/or residents. Appendix 2 contains two such systems sold by the subsidiary technology arms of two of the leading private infrastructure companies in the world, Veolia Environmental and Suez Environnement. There are similar systems available from other vendors. Christchurch City Council has recently installed such a system at its composting plant in Bromley in Christchurch. Beca understands the system was installed to provide quantitative data regarding the presence or otherwise of objectionable odour and to provide an on line management tool for both the operator and regulator. The essence of the tool is that it incorporates specialised sensors that detect specific chemical compounds associated with odours that you would typically expect from your site. This data is collected in real time and fed into a dispersion model. Information from a site weather station is also input into the model and the model then calculates the plume size based on site weather conditions and chemical compound concentrations measured by the site monitors. The system can be programmed with alarms to warn operators of developing odour issues. This allows operators to change site operations to avoid these problems. Data from the site can be shared with multiple users via the internet. The odour tools are not recommended as tools to enforce regulatory compliance but are very useful as site management and early warning tools. Living Earth has been using the Odatech system in Christchurch since April 2015 and is happy to discuss this system with PCC Staff. A major drawback with this technology is its cost. The cost of the Christchurch system, escalated to reflect foreign exchange movements at today’s date, is illustrated below.

a. Design, supply, install & commission & calibrate odour watch system (includes 3 e-nose units) NZ $ 391,000. b. Owners civil work NZ $ 94,364

Total NZ $ 485,364

Additional costs include some project management time. The costs could vary significantly at a different site as the civil works and number of detectors would likely be different. The costings above are GST exclusive and provided purely for indicative purposes and should not be construed as a costing for the Spicer Landfill site. This would require more detailed investigation and scoping.

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8 Recommendations

Beca recommends that the actions in Table 6 be implemented either as soon as practical or are integrated in to a variation to the current contract that would come into force on the 1 October 2016.

The risk tables in the current Spicer Landfill Asset Management Plan should be reviewed and updated taking into account the lessons learned through the recent run of odour and gas emission issues.

Whilst this report has not looked at environmental or technical issues associated with the design of the landfill, many of the current odour complaint issues can be reduced through the implementation of items in Table 6. This will take a conscious effort by parties to the contract, communicating strongly through robust contract platforms and parties delivering on their obligations under the revised contract.

The biosolids strategy currently under development by WWL could have a material impact on the future of the landfill. Biosolids currently make up approximately 14% to 16% of the total tonnage to the landfill (excluding cleanfill tonnages) and depending on the outcome of the strategy, biosolids could remain as they are, increase (if lime stabilised) or significantly decrease (if thermal drying or similar technologies adopted).

The Landfill owners may wish to consider the merits of installing “real time” odour monitoring technology as a method for providing 24 hour, 365 day per year monitoring of the facility. This technology can often assist operators to more tightly control sites that have the potential to produce offensive and objectionable odours through early warning of conditions that can cause complaints.

Beca is happy to provide any further assistance to PCC to implement the recommendations of this report.

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Appendix A

Porirua City Council Risk Assessment Tables for Spicer Landfill

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Appendix B

Real Time Odour Monitoring Technologies – Supplier Brochures

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Appendix C

Report Documentation Reference List

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DOCUMENTATION LIST Beca reviewed the following key documents in compiling this report. This list is not exclusive of all material viewed.

Draft Landfill Gas Management Plan – October 2015 Draft Spicer Landfill Operations Management Plan – 28 August 2015 GWRC Compliance Monitoring Report for 2013/14 dated 31 October 2014. GWRC Compliance Monitoring Report for 2011/12 for consent WGN 940046 dated 31 October 2012 GWRC Abatement Notice A807/A808 dated 17 June 2015 AECOM Report to ESL dated 19 August 2015 PCC and Tonkin and Taylor responses to AECOM report 28 September 2015 Biosolids test results supplied by Wellington Water Limited 1 Jan 2014 to 30 Oct 2015. PCC Spicer Landfill Asset Management Plan July 2014 Solid Waste Management (SWM) Reporting for years 2010/11 through to 2014/15

Documents

Report Spicer Landfill Odour Report - Porirua City · Steve Hutchinson (MWH Consultant) Jeremy McKibbin (WWLL Process Engineer) Mike Binns (WWLL WWTP Supervisor) Discussion on processing