Those reports shall, as a minimum, summarise the levels exceeding limit values, concentration caps, target values, long-term objectives, information thresholds and alert threshold, for the relevant averaging periods.

draw up, taking particular account of the comparability of the threshold values laid down by the Member States, the impact of those threshold values on the competitiveness of the economic sectors concerned, compliance with the deadlines laid down and an assessment of the progress made towards reducing groundwater pollution, a summary report and, if necessary, submit proposals for a directive amending the list of pollutants, groups of pollutants and indicators of pollution and/or related pollutant concentrations in accordance with the procedure laid down in Article 251 of the Treaty.

draw up, taking particular account of the comparability of the threshold values laid down by the Member States, the impact of those threshold values on the competitiveness of the economic sectors concerned, compliance with the deadlines laid down and an assessment of the progress made towards reducing groundwater pollution, a summary report and, if necessary, submit proposals for a directive amending the list of pollutants, groups of pollutants and indicators of pollution and/or related pollutant concentrations in accordance with the procedure laid down in Article 251 of the Treaty.

- draw up, taking particular account of the comparability of the threshold values laid down by the Member States, the impact of those threshold values on the competitiveness of the economic sectors concerned, compliance with the deadlines laid down and an assessment of the progress made towards reducing groundwater pollution, a summary report and, if necessary, submit proposals for a directive amending the list of pollutants, groups of pollutants and indicators of pollution and/or related pollutant concentrations in accordance with the procedure laid down in Article 251 of the Treaty.

2. At the latest by 22 June 2006, Member States shall provide the Commission with a list of all pollutants whose threshold value, on account of their natural concentration in a body of groundwater or group of bodies of groundwater, exceeds the values for which a threshold value pursuant to Annex I exists or an additional national threshold value has been established pursuant to Annex II. For each pollutant on the list, Member States shall provide the information set out in part B of Annex III to this Directive.

To maintain or improve the quality of ambient air, the European Union has established limit values for concentrations of sulphur dioxide, nitrogen dioxide and nitrogen oxides, particulate matter and lead, as well as alert thresholds for concentrations of sulphur dioxide and nitrogen oxide, in ambient air.