Volume Two 22. Lake Grassmere Salt Works Zone 22.3.6. Excavation. 22.3.6.1. Excavation in excess of 1000m must not occur on land with a slope greater 3 than 20° within any 24 month period. 22.3.6.2. Excavation must not be in, or within 8m of a river (except an ephemeral river when not flowing), lake (except during salt harvest operations) or the coastal marine area. 22.3.6.3. Wheeled or tracked machinery must not be operated in or within 8m of a river (except an ephemeral river or intermittently flowing river, when not flowing), lake (except during salt harvest operations) or the coastal marine area. 22.3.6.4. Batters must be designed and constructed to ensure they are stable and remain effective after completion of the excavation. 22.3.6.5. Water control measures and sediment control measures must be designed, constructed and maintained in an area disturbed by any excavation, such that the area is stable and the measures remain effective after completion of the excavation. The diameter of a culvert used to drain excavation must not be less than 300mm. 22.3.6.6. After reasonable mixing, excavation must not cause any conspicuous change in the colour or visual clarity of any flowing river, 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 excavation site; (c) the change in reflectance must be <50%. 22.3.7. Filling of land with clean fill. 22.3.7.1. The filling must not use commercial clean fill. 22.3.7.2. Filling in excess of 1000m must not occur within any 24 month period. 3 22.3.7.3. Fill must not be placed over woody vegetation on land with a slope greater than 10°. 22.3.7.4. A filled area must be designed, constructed and maintained to ensure it is stable and remains effective after completion of filling. 22.3.7.5. Water control measures and sediment control measures must be designed, constructed and maintained in a fill area, such that the area is stable and the measures remain effective after completion of the filling. The diameter of a culvert used to drain a fill area must not be less than 300mm. 22.3.7.6. When the filling has been completed the filled area must be covered with at least 200mm of soil, and sown down with a suitable vegetative cover other means to achieve a rapid vegetative cover must be used. 22.3.7.7. Filling must not be in, or within: (a) 8m of a river (except an ephemeral river when not flowing), lake or the coastal marine area; (b) 8m of the landward toe of a stopbank. 22 – 5