19. Open Space 3 Zone Volume Two (b) not be left in a position where it can enter, or be carried into, a river (except an ephemeral river), lake, Significant Wetland or the coastal marine area; (c) be stored on stable ground; (d) be managed to avoid accumulation to levels that could cause erosion or instability of the land. 19.3.4.6. Vegetation clearance must not cause any conspicuous change in the colour or visual clarity of a flowing river after reasonable mixing, or the water in a Significant Wetland, lake or costal marine area measured as follows: (a) hue must not be changed by more than 10 points on the Munsell scale; (b) the natural clarity must not be conspicuously changed due to sediment or sediment laden discharge originating from the vegetation clearance site; (c) the change in reflectance must be <50%. 19.3.5. Excavation. 19.3.5.1. There must be no excavation in excess of 1000m on any land with a slope 3 greater than 20 degrees within any 24 month period. 19.3.5.2. Excavation must not occur on any land with a slope greater than 35°. 19.3.5.3. Excavation must not be in, or within: (a) 8m of a river (except any ephemeral river when not flowing), lake or the coastal marine area; (b) 8m of a Significant Wetland or 30m of a river within a Water Resource Unit with a Natural State classification; (c) 8m of the landward toe of a stopbank and the depth of any excavation beyond that may not exceed 15% of the distance from the stopbank. 19.3.5.4. The excavation must not occur in a Soil Sensitive Area identified as loess soils. 19.3.5.5. Excavation must not be within such proximity to any abstraction point for a drinking water supply registered under section 69J of the Health Act 1956 as to cause contamination of that water supply. 19.3.5.6. Excavation must not be within a Level 2 or 3 Flood Hazard Area, or within the Level 4 Flood Hazard Area in the vicinity of Conders Overflow. 19.3.5.7. There must be no excavation in excess of 500m 3per Computer Register located within the Bryant Range, Upper Pelorus Area, Richmond Range Conservation Estate and Red Hills Range Outstanding Natural Feature and Landscape within any 12 month period. 19.3.5.8. There must be no excavation in excess of 500m per Computer Register 3 located within the Mt Duncan, Mount Rutland and Mount Cullen Outstanding Natural Feature and Landscape within any 12 month period. 19.3.5.9. There must be no excavation in excess of 500m per Computer Register 3 located within the Limestone Coastline Outstanding Natural Feature and Landscape within any 12 month period. 19.3.5.10. There must be no excavation in excess of 500m per Computer Register 3 located within the Marlborough Sounds Outstanding Natural Feature and Landscape within any 12 month period. 19 – 6