Kopeopeo Canal Contamination Remediation Project
Bay of Plenty Regional Council is working with the community to clean up dioxin contamination of the sediment in the Kopeopeo Canal. The canal was contaminated in the 1950s to late 1980s as a result of stormwater from the local sawmill which treated timber using Pentachlorophenol (PCP). The PCP contained dioxins as an impurity.
The Kopeopeo Canal Contamination Remediation project will use a staged approach to remove and safely store and bioremediate the contaminated sediment from the canal. A Project Steering Group has been set up to guide the project. It consists of representatives from Ngāti Awa, Sawmill Workers Against Poisons (SWAP), Whakatane Waimana Rivers Scheme Liaison Group, Ministry for the Environment and Bay of Plenty Regional Council.
We intend to use three separate sites for the bioremediation of the sediment removed from the canal. Up to 40,000 cubic metres of sediment will be removed. Map showing sites (8,313 KB).
Monitoring the Kopeopeo Canal will continue for several years after the contaminated sediment has been removed. The eels will be monitored annually until the Medical Officer of Health confirms they are safe to eat. We don't expect eel harvesting to be safe for two to five years.
The estimated cost of the project is $4.4 million, equally funded by the Ministry for the Environment through the Contaminated Sites Remediation Fund (CSRF) and Bay of Plenty Regional Council.
Find out more about the consent process for Kopeopeo Canal.
For more information check out frequently asked questions (24KB) or contact us.
We have completed the planning and design phase of the project. We are now in the consenting phase and in March 2013 Regional Council made a resource consent application which was publicly notified and open to submissions.
Bay of Plenty Regional Council's Natural Hazards group, as the applicant, has analysed submissions and met with submitters to clarify specific submission points or explain their response.
The consent authority reviewed the submissions received and determined they require further information from the applicant. This additional information was submitted to the consent authority on 21 October 2013.
A summary of the additional information is outlined below.
As the applicant, we will be sending our evidence to all submitters wishing to be heard on 2 December 2013.
A hearing date has been set for five days from 16 December 2013. Full details on the hearing date, process, and commissioners, is available on the consent page.
Summary of additional information
The key changes to the Kopeopeo Canal Remediation submission and areas where additional information has been provided are outlined below.
A detailed step-by-step description of the methodology for the project has been described in the Remediation Action Plan. There have been some changes to the methodology, the most significant include:
Dividing the remediation zone into 14 sections rather than 12. The remediation zone has not been extended; some sections have simply been modified to create a more consistent length.
Constructing the containment cells in the season prior to undertaking the excavation of sediments from the canal.
Increasing the height of bunds at Containment Site 1 to minimise the risk of water entering the containment cells in the event of a flood.
A revised dewatering process. This involves pumping water from one section to the next in an easterly direction and then pumping water into a treatment pond at Containment Site 3. The treatment pond will remove the majority of particulate matter before water is then pumped to a waterway that flows into the Whakatane River.
Further detail on the methodology has also been provided in response to questions raised in public meetings and submissions.
Further detail and clarification has been provided in sections of the AEE assessing the relevant planning documents, including Part 2 RMA 1991, the New Zealand Coastal Policy Statement, the Regional Coastal Environment Plan and the Regional Water and Land Plan.
An updated assessment of the effects of the loss of productive land on Containment Sites 1 and 2 has been provided.
An assessment of the potential for exposure to dioxins has been prepared. This technical report provides background on dioxins, explains the potential exposure pathways associated with the remediation work and considers the mitigation measures proposed to minimise exposure.
An Environmental Monitoring and Validation Plan has been prepared to provide details on how the works will be monitored and remediation will be validated.
A further assessment of the risk of flooding has been undertaken, including the potential for flooding during excavation activities and on the containment sites once excavation has been completed. On the basis of this work, it is now no longer proposed to remove bunds from the canal and allow floodwaters to flow through the remediation zone if a heavy rain event were to occur during the removal of sediments from the canal. Flood management measures have been developed that will enable water to be managed within the Rangitaiki Plains Drainage Scheme network without using this section of the Kopeopeo Canal.
The Groundwater and Soil Monitoring Plan has been incorporated into the Environmental Monitoring and Validation Plan and updated to provide further detail on the measures proposed to monitor potential effects on groundwater around the containment sites.
Further detail regarding the bioremediation process has been provided, including the implications of high water tables and flood events. Examples of other successful bioremediation projects have also been provided.
Earthworks machinery required to construct Containment Site 1 will access the site from State Highway 30 as these works will occur prior to the construction of the canal bunds.
A geotechnical assessment has been undertaken considering the seismic risks to the containment sites and the potential for settlement of containment site 3.
For more information, contact us - details below.