Surface Waters (Dangerous Substances) (Classification) Regulations (Northern Ireland) 1998

regulation 3(5)

SCHEDULE 5 Criteria for Classification DS5

1.  Subject to paragraph 2, the criteria for the classification DS5 are that—

(a) the annual mean concentration of each substance listed in column (1) of Table 6 in samples taken from the sampling point for the waters in question in accordance with regulation 4 does not exceed the relevant limit shown in column (2) of that Table; and

(b) subject to paragraph 3, the concentration of each substance listed in column (1) of Table 7 in each sample so taken does not exceed the relevant limit shown in column (2) of that Table.

2.  Where samples are taken in accordance with regulation 4 from more than one sampling point in relation to the waters in question, the criterion in paragraph 1(a) shall be satisfied in relation to the samples from each sampling point.

3.  In relation to dichlorvos used as a treatment for sea-lice infestation, compliance with the relevant limit in column (2) of Table 7 shall be determined by reference only to samples taken as nearly as may be after 24 hours have elapsed since it was so used.

TABLE 6

(1)	(2)
Substance	Limit (in microgrammes per litre) (annual mean)
Arsenic	25
Atrazine and Simazine	2 (for the two substances in total)
Azinphos-methyl	0.01
Dichlorvos	0.04
Endosulphan	0.003
Fenitrothion	0.01
Malathion	0.02
Trifluralin	0.1

TABLE 7

(1)	(2)
Substance	Limit (in microgrammes per litre)
Dichlorvos	0.6
Tributyltin	0.002
Triphenyltin and its derivatives	0.008