SITE MANAGEMENT PLAN PROPOSED RETIREMENT VILLAGE, 131 TO 147 CAVENDISH ROAD, CASEBROOK, CANTERBURY

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1 RILEY CONSULTANTS LTD New Zealand Web: AUCKLAND 4 Fred Thomas Drive, Takapuna, Auckland 0622 PO Box 253, North Shore, Auckland 0745 Tel: Fax: CHRISTCHURCH 395 Madras Street, Christchurch 8013 PO Box 4355, Christchurch 8140 Tel: Fax: Summerset Villages (Casebrook) Limited c/- Summerset Group Holdings Ltd PO Box 5187 Lambton Quay Wellington 6145 Our Ref: 13846/1-G Attention: Mr Vaughan Bell Dear Sir SITE MANAGEMENT PLAN PROPOSED RETIREMENT VILLAGE, 131 TO 147 CAVENDISH ROAD, CASEBROOK, CANTERBURY 1.0 Introduction The following letter has been prepared by (RILEY) at the request of Mr Vaughan Bell of Summerset Group Holdings Ltd, for a new retirement village at the above address. It has been prepared and reviewed by suitably qualified and experienced professionals. It is intended that this SMP will support a resource consent application to be submitted to Environment Canterbury (ECan) Information reviewed indicates activities have occurred on the site, which appear on the Ministry for the Environment s Hazardous Activities and Industries List (HAIL) as A10 Chemical Application/Pesticide and A17 Storage of tanks and drums for fuel, chemicals, or liquid waste. Findings stated in our previous reports, RILEY Refs: 13846/1-E and -F, indicate that the proposed development is classified as a restricted discretionary activity and requires consent under the National Environmental Standard for Assessing and Managing Contaminants in Soil to Protect Human Health, 2011 (NES). Therefore, this SMP outlines the site management actions required, for soil removal and disturbance for the proposed high density residential development. 1.2 Purpose of the SMP The SMP requires the adoption of good environmental management practices for the proposed site work activities, and identifies the mechanisms to be utilised to avoid, remedy, or mitigate potential adverse environmental effects. The SMP sets environmental control measures and documents risk-reducing procedures and plans to be implemented to achieve an acceptable level of risk for the proposed works. Sections in this report include: Site Details. Site Management Actions for Earthworks. Mitigation of Potential Environmental Effects. Contamination Health and Safety Plan. Management of Future Development/Excavation. Validation. GEOTECHNICAL CIVIL WATER RESOURCES

2 RILEY Ref: 13846/1-G Page Site Details 2.1 Site Identification The development area, comprises approximately 10ha (9.7ha) of greenfield site (RS 1600 Parts 1 and 2, Lots 1 to 4 DP 63972), adjacent to Cavendish Road, Casebrook. 2.2 Geology The geology is discussed in the previous Contamination Assessment, RILEY Ref: 13846/1-E, indicating the site is underlain by terrestrial deposits of the Springston Formation, consisting of sand and silt overbank deposits. 2.3 Site History The site history is discussed in our previous report, RILEY Ref: 13846/1-E. In summary, it was noted the site has been used for stock grazing and potentially for cultivation or market gardening. There were two residential sections, one with surrounding farm buildings for animal, fuel, chemical, and machinery storage situated centrally on the eastern boundary, and another on Lot 1 DP 63972, which also had a dwelling and sheds, possibly for farm use. 2.4 Proposed Development The existing rural site is to be developed into a retirement village as shown on the proposed Summerset development plan. The proposed development plan indicates construction is to comprise approximately 180 lightweight villas and townhouse units, 53 care apartments, and a stormwater detention pond, situated in the north-western part of the development. Significant earthworks will be required to re-profile the site, undertake subsurface ground improvements, and to excavate the stormwater detention pond up to an approximate depth of 1.2m. It is envisaged that excavated materials will be used on-site and geotechnically unsuitable material removed from the site. 2.5 Site Condition and Surrounding Environments Please refer to the previous report, RILEY Ref: E, dated 15 January Previous Reports Previous reports related to this SMP include the following: GHD Technical Due Diligence Report for RDT Pacific, 135 to 147 Cavendish Road, Land Investigation, October Contamination Assessment Proposed Retirement Village, 131 to 147 Cavendish Road, Casebrook, Canterbury, dated 15 January 2015, RILEY Ref: 13846/1-E. Soil Contamination Investigation for the Field/Paddock Areas, Proposed Retirement Village, dated 15 January 2015, RILEY Ref: 13846/1-F. The recent RILEY reports identified an area where soil contaminant concentrations exceed NES standards for the proposed development. Soils in other areas were found suitable for high density residential and recreational land use. However, any topsoil not required for reuse on-site would need to be disposed at a suitably licensed facility.

3 RILEY Ref: 13846/1-G Page 3 A restricted discretionary activity resource consent under the NES would be required for the following reasons: The proposed development involves a change in land use from agriculture to high density residential. Activities have occurred on the site, which appear on the HAIL (A10 and A17). Areas were identified where contaminant concentrations exceed applicable NES Soil Contaminant Standards. It was also noted that a contamination discharge consent may be required from Canterbury Regional Council. 3.0 Site Management Actions for Earthworks 3.1 Objectives Soil on two pieces of land associated with former dwellings and sheds, both situated on the eastern boundary, is to be removed off-site and disposed at an appropriately licensed facility. Given the soils in the shed area of the eastern central lot exceed NES Soil Contaminant Standards, delineation prior to removal and validation sampling will be required when soil has been removed. 3.2 Excavation and Disposal of Material in the Shed Area Shallow material in the shed area needs to be removed off-site and disposed at a suitable facility authorised to take such materials. The contaminated soil in the shed area, as indicated on RILEY Dwg: 13846/1-21, (up to 0.3m depth) will be removed at the beginning of the earthworks season (September/October 2015) prior to other site works, to avoid mixing and contaminating other soil. Prior to site works, sampling will be carried out to determine the depth of contamination. Then depending on the laboratory results the soil will be removed, and on completion, validation sampling will be carried out to confirm contaminated material has been removed. It is estimated site works will take up to four weeks. Location Description Sample Location Estimated Volume (m³) Area (m²) Shed Area CS21, CS22, CS26, CS Remainder of House Property with Sheds Lot 1 DP CV It is likely Christchurch City Council (CCC) Burwood landfill* will be a suitable location for disposal of contaminated material. It will be necessary to retain all tracking information for soil disposal, i.e. landfill receipts for each truckload, so that appropriate disposal methods can be confirmed in the validation report. *Although some contaminant concentrations exceeds Burwood Landfill criteria, Burwood Landfill has confirmed that contaminated soil will be acceptable if mixed and well diluted with material that has contaminant concentrations below landfill criteria.

4 RILEY Ref: 13846/1-G Page Validation Sampling Systematic sampling for 95% confidence using a square grid sampling pattern in accordance with Appendix B of the Ministry for Environment (MFE) Contaminated Land Management Guidelines No. 5 will be carried out following removal of contaminated soil in the vicinity of the former sheds. It should be noted the guidelines recommend a minimum of five samples for sites less than 500m². It is intended to test the base and to the sides of the excavations in accordance with relevant AC and MFE sampling guidelines. However, to sufficiently carry out validation in this area given the number of hot spots, up to 20 samples may be required. The validation samples will be analysed for the contaminants identified as exceeding screening criteria in the Contamination Assessment, RILEY Ref: 13846/1-E. Therefore, the validation sampling will test for arsenic and lead. It is intended to remove all contaminated ground that exceeds NES Soil Contaminant Standards. As part of the validation sampling, plans will be prepared for each location showing the site layout, material removed, locations sampled, and laboratory results for the validation report. 3.4 Excavation and Off-site Disposal for Other Parts of the Site. As discussed above, any topsoil not required for reuse on-site would need to be disposed at a suitably licensed facility. It is likely CCC Burwood Landfill will be a suitable location for disposal of contaminated material. It will be necessary to retain all tracking information for soil disposal, i.e. landfill receipts for each truckload, so that appropriate disposal methods can be confirmed in the validation report. 3.5 Unexpected Contaminated Material Should hazardous material be encountered outside of the identified area during site works, all works in the affected area shall cease and be inspected by RILEY. These areas will be assessed and managed in accordance with Council and MFE Guidelines. 4.0 Mitigation of Potential Environmental Effects A number of environmental protection measures will be put in place to mitigate potential environmental effects of the proposed earthworks. 4.1 Site Setup Prior to works commencing on-site, a number of structures and systems will be put in place to ensure the site is secure and appropriate health and safety requirements can be met. These include: Site works should be undertaken in fine weather. Contaminated areas should be cordoned off with appropriate fencing to avoid trafficking contaminated sediment to other parts of the property. To carry out delineation and remediation all three sites must be stock free to ensure sample location tags and markings are not disturbed. Excavators with long reaching buckets should be used to avoid tracking over contaminated areas. Appropriate washing facilities should be put in place for any equipment exposed to contamination.

5 RILEY Ref: 13846/1-G Page 5 Security fencing to prevent unauthorised access to the site in general. Signage including site works information, health and safety requirements, and site reporting requirements. Health and safety induction for site staff. More details of the proposed health and safety plan for the project are included in Section Stormwater and Sediment Control Stormwater and sediment control during work in areas where contaminant concentrations exceed NES Soil Contaminant Standards should be in accordance with the attached Remedial Action Sediment Control Plan, RILEY Dwg: /22. During excavation of contaminated soil, stormwater from open excavated areas should be collected and disposed of appropriately in accordance with CCC and ECan Regulations. Transpacific Technical Services Ltd is licensed to dispose of liquid wastes. Stormwater and sediment control requirements in general have been addressed within documentation supporting the Land Use Consent application (Refer RILEY report 13846/2- C). Additional details will be provided on the staging of earthwork activities and management of runoff for the Building Consent application in accordance with the approved consent and ECan Erosion and Sediment Control Guidelines, Dust Control During windy conditions, there is the potential for dust to migrate from the earthworks areas. A water truck or portable water sprays will be used in trafficked areas to dampen dust during dry and windy conditions. Work will cease in excessively windy conditions. Dust control will be carried out in accordance with the ECan Erosion and Sediment Control Guidelines, Odour Control If odours of any description are noted in soil or surface water during the site works, all work will cease until an appropriately qualified consultant has assessed the potential risks from the odours and advised on health and safety requirements. 4.5 Noise Control Noise levels will be kept within levels set by local authorities and only during normal working hours. 4.6 Services Checks will be made for existing services in areas of proposed site works. Care will be taken to not jeopardise the integrity of services during the site works. 4.7 Health and Safety Procedures The contractor will prepare a site specific health and safety plan covering all relevant matters and this health and safety plan will be a component of the contractor s Plan. All workers will be inducted prior to being involved in carrying out works at the site. Excavation work to remove contamination should not be any greater than 0.3m deep. Confined spaces health and safety requirements are needed for trench excavations of more than 0.5m depth, whereby a project manger s input would be needed.

6 RILEY Ref: 13846/1-G Page 6 Any site staff undertaking works in soil on-site (i.e. drainage or other inground services) will be advised to wear neck to toe clothing and gloves. A dedicated washroom facility will be provided for staff to wash hands before leaving site or taking breaks. The site will be designated as either smoke-free, or, if smoking is permitted, this must only be in a designated smoking area in accordance with relevant occupational health requirements. Machinery should not track over the ground inferred to be contaminated. All material for removal should be loaded in such a way to avoid spilling onto clean ground. Trucks should have high sides with sealable covers. Following removal of contaminated soil, equipment exposed to contamination should be decontaminated and dirty water collected and carted off-site by a licensed organisation such as Transpacific Technical Services Ltd. 4.8 Emergency Procedures The following contact details should be used in an emergency: Emergency Fire, Ambulance, Police Phone: 111 Nearest Hospital Christchurch Hospital 2 Riccarton Avenue Christchurch Central Christchurch 4710 Phone: Nearest A&E Bealey 24 Hour Surgery Corner Bealey Avenue and Colombo Street Christchurch 8014 Phone: Management of Future Development/Excavation Future development and excavation should be assessed according to the proposed activities to be carried out on the specific piece of land being developed or excavated. 6.0 Validation A site validation report (SVR) will be prepared after completion of the site works in accordance with MFE Guidelines (Contaminated Land Management Guidelines No.1, Reporting on Contaminated Sites in New Zealand, November 3). The SVR for the site will document the following: Confirmation that earthworks were carried out in accordance with the SMP. Confirmation that appropriate disposal methods have been carried out for material taken off-site. Confirmation that remaining soil contaminant concentrations are less than NES Soil Contaminant Standards for high density residential land use Confirmation of the quality of any material imported to the site.

7 RILEY Ref: 13846/1-G Page Limitation This report has been prepared solely for the benefit of Summerset Group Holdings Ltd as our client with respect to the brief. The reliance by other parties on the information or opinions contained in the report shall, without our prior review and agreement in writing, be at such parties sole risk. has performed the services for this project in accordance with the standard agreement for consulting services and current professional standards for environmental site assessment. No guarantees are either expressed or implied. There is no investigation which is thorough enough to preclude the presence of materials at the site which presently, or in the future, may be considered hazardous. Because regulatory evaluation criteria are constantly changing, concentrations of contaminants present and considered to be acceptable may, in the future, become subject to different regulatory standards which cause them to become unacceptable and require further remediation for this site to be suitable for the existing or proposed land use activities. Opinions and judgements expressed herein are based on our understanding and interpretation of current regulatory standards, and should not be construed as legal opinions. Where opinions or judgements are to be relied on they should be independently verified with appropriate legal advice. would be pleased to provide further services if needed to Summerset Group Holdings Ltd and believes the project would benefit from such continuity. If you have any queries, please contact the undersigned. Yours faithfully RILEY CONSULTANTS LTD Prepared by: Reviewed and approved for issue by: Joanne McClean Engineering Geologist Rob Burden Director Resource Development Enc: Environmental Sampling Plan, RILEY Dwg: 13846/1-21 Remedial Action Sediment Control Plan, RILEY Dwg: 13846/1-22

8 LEGEND NOTES: RILEY CONSULTANTS SUMMERSET VILLAGES (CASEBROOK) LTD. PROPOSED RETIREMENT VILLAGE - CAVENDISH ROAD, CHRISTCHURCH COMPLETED ENVIRONMENTAL SAMPLING - SITE PLAN 13846/

9 TYPICAL SEDIMENT CONTROL AT LOCATIONS OF POTENTIAL SURFICIAL CONTAMINATION SCALE N.T.S. RILEY CONSULTANTS SUMMERSET VILLAGES (CASEBROOK) LTD. PROPOSED RETIREMENT VILLAGE - CAVENDISH ROAD, CHRISTCHURCH REMEDIAL ACTION SEDIMENT CONTROL - TYPICAL DETAILS 13846/1-22 0