Volume One 15. Resource Quality (Water, Air, Soil) (iii) avoiding or remedying the effects of increased sodium levels; (b) maintain nutrients at appropriate levels; and (c) retain topsoil in situ. This policy recognises that while soil structural degradation, nutrient depletion/enrichment and accelerated soil erosion are not of widespread concern in Marlborough, there is a long term risk that irreversible degradation in soil quality may occur if appropriate land management practices are not used. The Council will work with rural industry groups to ensure that land management practices address the potential for unnecessary soil compaction, accelerated soil erosion, retention of organic matter and increased soil sodium concentrations and nutrient levels. Subsequently, some existing land uses may continue while elsewhere adjustments and changes to land management practices may be required. The Council may also undertake joint investigations with rural industry groups to gain a better understanding of the impact of particular rural land use activities and land management practices on the soil resource. [R] Policy 15.4.3 – Control land disturbance activities to retain topsoil and minimise the potential for eroded soil to degrade water quality in lakes, rivers, significant wetlands and coastal waters. Land disturbance is any activity that involves excavation, filling, cultivation or vegetation clearance. Each of these activities has the potential to expose bare soil to the elements. This policy signals that these activities are to be controlled in the rural, coastal and urban environments. The controls will be used to ensure that the potential for accelerated soil erosion and water quality degradation created as a result of land disturbance is minimised. Where there is certainty that activities undertaken in a particular way will protect the soil and water resource, control can take the form of enabling rules. However, where there is uncertainty about the effect of the land disturbance activity, a discretionary activity rule will be used. The use of these rules reflects the importance of the soil resource to the social and economic wellbeing of Marlborough, particularly for retaining primary production options for rural resource users. The policy also recognises the potential for runoff contaminated with sediment to adversely affect water quality and seeks to manage the effects of land disturbance on water quality in an integrated manner. The use of the controls detailed here will ensure that soil and water resources are conserved for current and future generations. Land disturbance is also controlled through the National Environmental Standard for Assessing and Managing Contaminants in Soil to Protect Human Health 2011, where there is a risk that the soil is contaminated to the extent of being a risk to human health. In these circumstances, the NES sets out the status of disturbing contaminated soil through rules and allows consideration of the appropriateness of the disturbance, given the amount and kind of soil contamination. The rules of the NES provide procedures to manage the risk of disturbing contaminated soil on human health only, and do not extend to the purpose of soil conservation. [R] Policy 15.4.4 – In considering any land use consent application to undertake land disturbance, regard shall be had to: (a) the physical characteristics of the site, including soil type, slope and climate; (b) any industry standards that are relevant to the activity; (c) sediment and erosion control measures required to reasonably minimise adverse effects caused by rainfall events, including the use of setbacks from waterbodies; (d) the proximity of the land disturbance to any fresh waterbody or coastal water and the potential for eroded soil to reach the waterbody or coastal waters; 15 – 39