Approximately 14,000 sites make uip trhe Historical Land Use Database. All of these were analysed for the potential of Mercury land Contamination during the production of the main report (See Annex A). Of these, 25 individual sites were initially given a "High" risk rating during the original desktop analysis. However, these 25 sites were subsequently reviewed by NIEA Scientists, and, following this additional analysis, all of them were re-classified as having "Low" risk. This was as a function of, for example, changes in or developement of the land since the original land use was identified, or the available evidence does not support that risk rating based on what is known about the actual industries or processes that took place at that particular site.
