7. Coastal Living Zone Volume Two 7.3.9.9. A filled area must be designed, constructed and maintained to ensure it is stable and remains effective after completion of filling. 7.3.9.10. Water control measures and sediment control measures must be designed, constructed and maintained in all areas disturbed by any excavation or filling, such that the areas are stable and the measures remain effective after completion of the excavation or filling. The diameter of a culvert used to drain excavation or fill area must not be less than 300mm. 7.3.9.11. Excavation or filling must not occur on a slope greater than 7.5° if the activity is within a Soil Sensitive Area identified as loess soils. 7.3.9.12. For staged excavation or filling, any part of the excavation or filled area that has not been further developed within 12 months must be re-vegetated. 7.3.9.13. Where the excavation or filling results in areas of exposed soil, those areas must be re-vegetated within 12 months of the completion of the excavation or filling. 7.3.9.14. The fill must not contain any: (a) hazardous substances; (b) combustible or organic materials; (c) any other contaminant subject to chemical or biological breakdown; (d) liquids or sludge. 7.3.10. Excavation or filling within the National Grid Yard. 7.3.10.1. Excavation within the National Grid Yard in the following circumstances is exempt from the remaining standards under this rule: (a) excavation that is undertaken as part of agricultural or domestic cultivation, or repair, sealing or resealing of a road, footpath, driveway or farm track; (b) excavation of a hole, not exceeding 500mm in diameter, that is more than 1.5m from the outer edge of a pole support structure or stay wire; (c) excavation of a hole, not exceeding 500mm in diameter, that is a post hole for a farm fence or horticulture structure and more than 5m from the visible outer edge of a tower support structure foundation. 7.3.10.2. The excavation must be no deeper than 300mm within 6m of the outer visible edge of a transmission tower support structure. 7.3.10.3. The excavation must be no deeper than 3m between 6m and 12m of the outer visible edge of a transmission tower support structure. 7.3.10.4. The excavation must not compromise the stability of a National Grid support structure. 7.3.10.5. The filling must not result in a reduction in the ground to conductor clearance distances as required in Table 4 of the New Zealand Electrical Code of Practice (NZECP34:2001). 7.3.11. Application of an agrichemical into or onto land. 7.3.11.1. The agrichemical must be approved for use under the Hazardous Substances and New Organisms Act 1996. 7.3.11.2. The application must be undertaken in accordance with the most recent product label. All spills of agrichemicals above the application rate must be notified to Council immediately. 7 – 8