9.—(1) This regulation applies in respect of each zone in which—
(a)concentrations of one or more Group B pollutants exceed the relevant target value; or
(b)concentrations of ozone are equal to or below the target values, but exceed a long-term objective.
(2) Where paragraph (1)(a) applies, the Department shall—
(a)identify the cause of the pollution and the predominant sources of emissions; and
(b)in relation to the pollutants concerned, ensure that the measures required by regulation 7(2) are directed in particular at the sources of emissions identified.
(3) Where paragraph (1)(b) applies, the Department shall prepare and implement measures which it considers to be cost-effective with the aim of attaining the long-term objective.
(4) The Department shall ensure that the measures required in paragraph (3) are consistent with the improvement plans prepared for ozone under regulation 8(3).