Volume Two 22. Lake Grassmere Salt Works Zone (a) 2000m in any 5 year period where the average canopy height is 2 between 3m and 6m; (b) 10000m in any 5 year period where the average canopy height is 2 below 3m, except for the following species where clearance in any 5 year period must not exceed: (i) 500m of indigenous sub-alpine vegetation; 2 (ii) 100m of tall tussock of the genus Chinochloa. 2 22.3.9. Non-indigenous vegetation clearance. 22.3.9.1. Where clearance is by mechanical means, blading or root-raking by bulldozer must not be used on slopes greater than 20°. 22.3.9.2. Vegetation must not be removed by fire or mechanical means within 8m of a river (except an ephemeral river, or intermittently flowing river when not flowing), lake or the coastal marine area. 22.3.9.3. No tree or log must be dragged through the bed of a river (except an ephemeral river or intermittently flowing river, when not flowing), lake or through the coastal marine area. 22.3.9.4. 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 or the coastal marine area. 22.3.9.5. On completion of a vegetation clearance, a suitable vegetative cover that will mitigate soil loss, must to be restored on the site so that, within 24 months the amount of bare ground is to be no more than 20% greater than prior to the vegetation clearance taking place. 22.3.9.6. The depth of topsoil removed must not exceed more than 20mm over more than 15% of any vegetation clearance site. 22.3.9.7. Woody material greater than 100mm in diameter and soil debris must: (a) not be left within 8m of, or deposited in, a river (except an ephemeral river or intermittently flowing river, when not flowing), lake or the coastal marine area; (b) not be left in a position where it can enter, or be carried into, a river (except an ephemeral river), lake 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. 22.3.9.8. After reasonable mixing, vegetation clearance must not cause any conspicuous change in the colour or visual clarity of a 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 vegetation clearance site; (c) the change in reflectance must be <50%. 22 – 7