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

regulations 3(1) and 4(4)

SCHEDULE 1 Criteria for Classification DS1

The criteria for the classification DS1 are that the annual mean concentration of each substance listed in column (1) of Table 1 in samples taken from the sampling point for the waters in question in accordance with regulation 4 does not exceed the relevant limit specified in column (2) of that Table.

TABLE 1

(1)	(2)	(3)
Substance	Concentration in microgrammes per litre (annual mean)	Reference method of measurement
(1) The accuracy and precision of the method must be plus or minus 50% at a concentration which represents twice the value of the limit of determination. (2) The accuracy and precision of the method must be plus or minus 30%.
Aldrin Dieldrin Endrin Isodrin	0.01 0.01 0.005 0.005	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent with a limit of determination of 2.5 ng/1(1).
Cadmium and its compounds	5 (total cadmium: both soluble and insoluble forms)	Atomic absorption spectrophotometry after preservation and suitable treatment of the sample. The limit of determination is .25 µg/litre(2).
Carbon tetrachloride	12	Gas chromatography. The limit of determination is 0.1 µg/litre(1).
Chloroform	12	Gas chromatography. The limit of determination is 0.1 µg/1itre(1).
DDT (all isomers)	0.025	Gas chromatography with electron capture detection after extraction by means of a suitable solvent. The limit of determination for total DDT is approximately 4 ng/l, depending on the number of extraneous substances present in the sample(1).
para-para-DDT	0.01	Gas chromatography with electron capture detection after extraction by means of a suitable solvent. The limit of determination for total DDT is approximately 4 ng/l, depending on the number of extraneous substances present in the sample(1).
Hexachlorobenzene	0.03	Gas chromatography with electron capture after extraction by means of an appropriate solvent. The limit of determination shall be within the range 1 to 10 ng/1 depending on the number of extraneous substances present in the sample(1).
Hexachlorobutadiene	0.1	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent. The limit of determination shall be within the range 1 to 10 ng/1, depending on the number of extraneous substances present in the sample(1).
Hexachlorocyclohexane (all isomers)	0.1	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent. The limit of determination shall be within the range 1 to 10 ng/1 depending on the number of extraneous substances present in the sample(1).
Mercury and its compounds	1 (total mercury: both soluble and insoluble forms)	Flameless atomic absorption spectrophotometry after suitable pre-treatment of the sample which takes account in particular of pre-oxidation of the mercury and of successive reduction of the mercury ions Hg(II). The limit of detection must be 0.1 µg/litre(2).
Pentachlorophenol and its compounds	2	High pressure liquid chromatography or gas chromatography with electron capture detection after extraction by means of a suitable solvent. The limit of determination is 0.1 µg/litre(1).

regulations 3(2) and 4(4)

SCHEDULE 2 Criteria for Classification DS2

The criteria for the classification DS2 are that the annual mean concentration of each substance listed in column (1) of Table 2 in samples taken from the sampling point for the waters in question in accordance with regulation 4 does not exceed the relevant limit specified in column (2) of that Table.

TABLE 2

(1)	(2)	(3)
Substance	Concentration in microgrammes per litre (annual mean)	Reference method of measurement
(1) The accuracy and precision of the method must be plus or minus 50% at a concentration which represents twice the value of the limit of determination. (2) The accuracy and precision of the method must be plus or minus 30%.
Aldrin Dieldrin Endrin Isodrin	0.01 0.01 0.005 0.005	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent with a limit of determination of 2.5 ng/1(1).
Cadmium and its compounds	2.5 (dissolved cadmium)	Atomic absorption spectrophotometry after preservation and suitable treatment of the sample. The limit of determination is .25 µg/litre(2).
Carbon tetrachloride	12	Gas chromatography. The limit of determination is 0.1 µg/litre(1).
Chloroform	12	Gas chromatography. The limit of determination is 0.1 µg/litre(1).
DDT (all isomers)	0.025	Gas chromatography with electron capture detection after extraction by means of a suitable solvent. The limit of determination for total DDT is approximately 4 ng/l, depending on the number of extraneous substances present in the sample(1).
para-para-DDT	0.01	Gas chromatography with electron capture detection after extraction by means of a suitable solvent. The limit of determination for total DDT is approximately 4 ng/l, depending on the number of extraneous substances present in the sample(1).
Hexachlorobenzene	0.03	Gas chromatography with electron capture after extraction by means of an appropriate solvent. The limit of determination shall be within the range 1 to 10 ng/1 depending on the number of extraneous substances present in the sample(1).
Hexachlorobutadiene	0.1	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent. The limit of determination shall be within the range 1 to 10 ng/1, depending on the number of extraneous substances present in the sample(1).
Hexachlorocyclohexane (all isomers)	0.02	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent. The limit of determination shall be within the range 1 to 10 ng/1 depending on the number of extraneous substances present in the sample(1).
Mercury and its compounds	0.3 (dissolved mercury)	Flameless atomic absorption spectrophotometry after suitable pre-treatment of the sample which takes account in particular of pre-oxidation of the mercury and of successive reduction of the mercury ions Hg(II). The limit of detection must be .03 µg/litre(2).
Pentachlorophenol and its compounds	2	High pressure liquid chromatography or gas chromatography with electron capture detection after extraction by means of a suitable solvent. The limit of determination is 0.1 µg/litre(1).

regulations 3(3) and 4(4)

SCHEDULE 3 Criteria for Classification DS3

The criteria for the classification DS3 are that the annual mean concentration of each substance listed in column (1) of Table 3 in samples taken from the sampling point for the waters in question in accordance with regulation 4 does not exceed the relevant limit specified in column (2) of that Table.

TABLE 3

(1)	(2)	(3)
Substance	Concentration in microgrammes per litre (annual mean)	Reference method of measurement
Note The accuracy and precision of the method must be plus or minus 50% at a concentration which represents twice the value of the limit of determination.
1,2-Dichloroethane	10	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent or gas chromatography following isolation by means of the “purge and trap” process and trapping by using a cryogenically cooled capillary trap. The limit of determination is 1 µg/litre. (see Note)
Trichloroethylene Perchloroethylene	10 10	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent. The limit of determination is 0.1 µg/litre. (see Note)
Trichlorobenzene	0.4 (but there must be no significant increase over time in the concentration of trichlorobenzene in sediments and/or molluscs and/or shellfish and/or fish)	Gas chromatography with electron capture detection after extraction by means of an appropriate solvent or, when used to determine the concentration in sediments and organisms, after appropriate preparation of the sample. The limit of determination for each isomer separately is 10 ng/1 for the water environment and 1 µg/kg of dry matter for sediments and organisms. (see Note)

regulation 3(4)

SCHEDULE 4 Criteria for Classification DS4

1.  Subject to paragraph 2, the criteria for the classification DS4 are that—

(a) the annual mean concentration of each substance listed in column (1) of Table 4 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) the concentration of each substance listed in column (1) of Table 5 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.

TABLE 4

(1)	(2)
Substance	Limit (in microgrammes per litre) (annual mean)
Arsenic	50
Atrazine and Simazine	2 (for the two substances in total)
Azinphos-methyl	0.01
Dichlorvos	0.001
Endosulphan	0.003
Fenitrothion	0.01
Malathion	0.01
Trifluralin	0.1

TABLE 5

(1)	(2)
Substance	Limit (in microgrammes per litre)
Triphenyltin and its derivatives	0.02
Tributyltin	0.02

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

regulation 3(6)

SCHEDULE 6 Criteria for Classification DS6

1.  Subject to paragraph 2, the criteria for the classification DS6 are that—

(a) the annual mean concentration of each substance listed in column (1) of Table 8 in samples taken from the sampling point for the waters in question in accordance with regulation 4 does not exceed the relevant concentration specified in column (2) of that Table; and

(b) the concentration of mevinphos in each sample so taken does not exceed 0.02 microgrammes per litre.

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.

TABLE 8

(1)	(2)
Substance	Annual mean concentration in microgrammes per litre
4-Chloro-3-methyl-phenol	40
2-Chlorophenol	50
2,4-Dichlorophenol	20
2,4-D (ester)	1
(non-ester)	40
1,1,1-Trichloroethane	100
1,1,2-Trichloroethane	400
Bentazone	500
Benzene	30
Biphenyl	25
Chloronitrotoluenes	10
Demeton	0.5
Dimethoate	1
Linuron	2
Mecoprop	20
Naphthalene	10
Omethoate	0.01
Toluene	50
Triazaphos	0.005
Xylene	30

regulation 3(7)

SCHEDULE 7 Criteria for Classification DS7

1.  Subject to paragraph 2, the criteria for the classification DS7 are that the annual mean concentration of each substance listed in column (1) of Table 9 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.

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 shall be satisfied in relation to the samples from each sampling point.

TABLE 9

(1)	(2)
Substance	Limit (in microgrammes per litre) (annual mean)
4-Chloro-3-methyl-phenol	40
2-Chlorophenol	50
2,4-Dichlorophenol	20
2,4-D (ester)	1
(non-ester)	40
1,1,1-Trichloroethane	100
1,1,2-Trichloroethane	300
Bentazone	500
Benzene	30
Biphenyl	25
Chloronitrotoluenes	10
Demeton	0.5
Dimethoate	1
Linuron	2
Mecoprop	20
Naphthalene	5
Toluene	40
Triazaphos	0.005
Xylene	30