Management & Monitoring Plan
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This document was approved by GWRC *-----TBA----- * 2015. It supersedes all previous management plans for the project. A copy of this document must be supplied to all parties working on the pipeline, and available on site at all times. WCC’s Western Wellington Wastewater Treatment Plant (WWTP) Main Outfall Pipeline (Karori Stream to Makara Coast) Management & Monitoring Plan Prepared for: Wellington Water On behalf of Wellington City Council October 2015 Cardno Ref: NZ01-14121 Wellington Water Ref: PO 0000008830 Karori Main Outfall Pipeline Management & Monitoring Plan Contact Information Document Information Cardno Limited Prepared for Wellington City Council Trading as Cardno (NZ) Limited Project Name Management & Company No: 036749 Monitoring Plan File Reference NZ0114121-PL- (Wellington / Head Office) Management & 25 Victoria Street, Petone, Lower Hutt 5012 Monitoring Plan-Karori MOP-FINAL 5 Oct 15-v5 PO Box 38-098, Wellington Mail Centre, Petone I.docx Lower Hutt 5045, New Zealand Project Reference NZ0114121 Telephone: (04) 478-0342 Date October 2015 [email protected] www.cardno.com Document Control Date Description Author Author Reviewer Initials (Signature) Version 1 08/08/2014 Draft Management Plan for Client Comment JKG 1A 21/08/2014 Draft following comment for client approval JKG 1B 09/09/2014 As above – additional client input added JKG 1C 3/10/2014 Final Draft for Submission to GWRC with final JKG client comments added 1D 22/10/2014 Final amendments as agreed with client JKG Anna Hector following additional client input 1E 25/06/2015 Final Draft for GWRC Consultation – allowed JKG Anna for fish rescue methodology to be appended. Hector/GWRC 1F 16/08/15 Final Draft (v3) for DOC Consultation (report JKG Anna Hector dates amended) 1G 24/08/15 Final Draft (v4) for landowner Consultation JKG Anna Hector (report date amended) 1H 05/10/15 Final (v5) Removed draft comments – for JKG Anna Hector lodgement. Key Abbreviations used in this MMP GWRC Greater Wellington Regional Council MOP Main Outfall Pipeline MMP Management & Monitoring Plan WCC Wellington City Council WWTP Wellington City Council’s Western Wastewater Treatment Plant © Cardno 2012. Copyright in the whole and every part of this document belongs to Cardno and may not be used, sold, transferred, copied or reproduced in whole or in part in any manner or form or in or on any media to any person other than by agreement with Cardno. This document is produced by Cardno solely for the benefit and use by the client in accordance with the terms of the engagement. Cardno does not and shall not assume any responsibility or liability whatsoever to any third party arising out of any use or reliance by any third party on the content of this document. October 2015 i Karori Main Outfall Pipeline Management & Monitoring Plan QUICK REFERENCE SUMMARY This Management & Monitoring Plan (MMP) supports a 2014 application by Wellington City Council for New “Global” Resource Consents to enable Wellington Water (or their representatives) to undertake (on behalf of Wellington City Council, WCC) a range of planned and unplanned maintenance and repairs along the Main Outfall Pipeline (MOP) from WCC’s Western Wastewater Treatment Plant (WWTP) to the Ocean Outfall on Wellington’s South Coast. The MMP also covers the requirements of the WWTP Discharge Permit WGN060283 [25226] relating to inspection and maintenance of the integrity of the wastewater pipeline until it is replaced (replacement is required to have occurred by 31 December 2023). Condition 22 of the consent requires the MOP to be managed and monitored to avoid, remedy and mitigate adverse effects of treated wastewater discharges to the Karori Stream associated with leaks or failures of the aging pipeline. Condition 23 requires annual reporting on the MOP covering inspections, observations, repairs and planned remedial activities over the previous year. This MMP supersedes all previously prepared MMP documents submitted to Greater Wellington Regional Council (GWRC) for approval. It has been prepared in a format that enables it to be referenced in conditions of resource consent and to be used as the stand alone document for administration, monitoring and compliance purposes. The information contained within this MMP is intended to meet the requirements of GWRC, and has been prepared with reference to GWRC’s “Erosion and Sediment Control Guidelines for the Wellington Region (September 2002) and other related documents (including existing consents), referenced later. This MMP must be read and implemented as part of any contract documentation prior to commencement of earthworks on the site. Emphasis is placed on the avoidance, mitigation or remediation of potential adverse effects on surrounding properties and the aquatic habitat values of the Karori Stream as a direct result of any maintenance and repair works. As the Karori Stream environment is dynamic and conditions are constantly changing, the proposed works have been described as a series of possible scenarios to suit the typical conditions in the different parts of the stream along the length of the pipeline. However, variations to the proposed methodologies may be required on a case by case basis to maintain protection of downstream environments (e.g. from sediment released by stream bed disturbance) while also working within local site constraints. Any changes to this MMP must be submitted for approval to GWRC and written approval obtained in advance of actions made on site. The approved variations shall be appended to this document as a permanent record. Advisory Note: This MMP document brings together all relevant information required to support the monitoring and management requirements of Condition 22 of WGN060283 [25226] and address relevant environmental effects to the required acceptable standard under the Regional Freshwater Plan for the Wellington Region. This MMP supersedes all previous advice and information and all previously approved documents. It does not cover any other monitoring. Copies of the relevant resource consents are to be included in the contract documents. October 2015 ii Karori Main Outfall Pipeline Management & Monitoring Plan TABLE OF CONTENTS 1. INTRODUCTION & SCOPE OF DOCUMENT .....................................................................5 1.1 Compliance and Amendments ....................................................................................6 1.2 Reference Documents ................................................................................................6 1.3 Legal Descriptions of Land Accessed for Pipeline Maintenance ................................ 6 2. REGIONAL PLAN & RESOURCE CONSENT REQUIREMENTS ...................................... 7 2.1 WGN060283 [25226] Condition 22 ............................................................................. 7 2.2 WGN060283 [25226] Condition 23 ............................................................................. 8 2.3 Requirements of Other Consent Conditions ............................................................... 8 2.4 Repairs to Date ........................................................................................................... 8 2.5 New Consents Required to Undertaken Repairs & Maintenance ............................... 9 2.6 Works within Sensitive Catchments ............................................................................ 9 2.7 Limitations to Monitoring covered in this MMP ........................................................... 9 3. LOCATION & ACCESS INFORMATION ..........................................................................10 4. THE MAIN OUTFALL PIPELINE (MOP) ........................................................................... 12 5. INSPECTIONS ................................................................................................................... 17 5.1 Consent Requirements ............................................................................................. 17 5.2 Frequency of Pipeline Inspections ............................................................................ 17 5.3 Procedures for Inspections .......................................................................................18 5.3.1 All Inspections ............................................................................................... 18 5.3.2 Event Based Inspections .............................................................................. 18 5.3.3 Annual Inspections ....................................................................................... 19 5.4 Procedures for Identifying & Recording Faults in the Pipeline .................................. 19 5.5 Procedure for Flow Monitor Data Capture ................................................................ 23 5.5.1 In the Office .................................................................................................. 23 5.6 Sampling & Assessment Procedure ......................................................................... 24 5.6.1 Testing for Suspected Pipeline Leaks ..........................................................24 5.6.2 Sampling Technique ..................................................................................... 24 5.6.3 Sample Storage & Transfer to Laboratory .................................................... 24 5.6.4 Sample Assessment ..................................................................................... 25 5.7 Follow-Up ..................................................................................................................25