Division BAT 10 BAT is to carry out the monitoring of emissions to water, as indicated below, with the indicated frequency and according to EN standards. If EN standards are not available, BAT is to use ISO, national or other international standards that ensure the provision of data of an equivalent scientific quality.

United Kingdom

	Parameter	Monitoring frequency	Monitoring associated with
There is a trend to replace COD by TOC for economic and environmental reasons. If TOC is already measured as a key process parameter, there is no need to measure COD; however, a correlation between the two parameters should be established for the specific emission source and waste water treatment step.
Rapid test methods can also be used. The results of rapid tests should be checked regularly (e.g. monthly) against EN standards or, if EN standards are not available, against ISO, national or other international standards which ensure the provision of data of an equivalent scientific quality.
For mills operating less than seven days a week, the monitoring frequency for COD and TSS may be reduced to cover the days the mill is in operation or to extend the sampling period to 48 or 72 hours.
Applicable where EDTA or DTPA (chelating agents) are used in the process.
Not applicable to plants that provide evidence that no AOX is generated or added via chemical additives and raw materials.
a	Chemical oxygen demand (COD) or Total organic carbon (TOC)^f1	Daily^f2 ^f3	BAT 19 BAT 33 BAT 40 BAT 45 BAT 50
b	BOD₅ or BOD₇	Weekly (once a week)
c	Total suspended solids (TSS)	Daily
d	Total nitrogen	Weekly (once a week)
e	Total phosphorus	Weekly (once a week)
f	EDTA, DTPA^f4	Monthly (once a month)
g	AOX (according to EN ISO 9562:2004)^f5	Monthly (once a month)	BAT 19: bleached kraft
g	AOX (according to EN ISO 9562:2004)^f5	Once every two months	BAT 33: except TCF and NSSC mills BAT 40: except CTMP and CMP mills BAT 45 BAT 50
h	Relevant metals (e.g. Zn, Cu, Cd, Pb, Ni)	Once a year

Annotations

Footnotes

f1: There is a trend to replace COD by TOC for economic and environmental reasons. If TOC is already measured as a key process parameter, there is no need to measure COD; however, a correlation between the two parameters should be established for the specific emission source and waste water treatment step.
f2: Rapid test methods can also be used. The results of rapid tests should be checked regularly (e.g. monthly) against EN standards or, if EN standards are not available, against ISO, national or other international standards which ensure the provision of data of an equivalent scientific quality.
f3: For mills operating less than seven days a week, the monitoring frequency for COD and TSS may be reduced to cover the days the mill is in operation or to extend the sampling period to 48 or 72 hours.
f4: Applicable where EDTA or DTPA (chelating agents) are used in the process.
f5: Not applicable to plants that provide evidence that no AOX is generated or added via chemical additives and raw materials.