With the lower growth scenarios, it will not be possible to mitigate to any significant extent some of the existing adverse impacts or risks to existing employment levels. With the higher growth scenarios, the greatest potential adverse impact would be from road traffic but this could be mitigated to result in a significant improvement compared to today by better public transport, enhanced cycling and walking routes and extensive travel planning. Other adverse impacts such as noise or the effects on ecology or water quality can also be mitigated by stricter controls applied to new types of airport activity. Sustainability involves a balance of positive and negative impacts and the positive benefits of employment growth are part of this equation.