The ammonia nitrogen objective is an average of at least 5 weekly samples taken in a period of 30 days during low river flow.
(The ammonia nitrogen objective; is; an average of at least 5 weekly samples) (at least 5 weekly samples; taken; T:in a period of 30 days; T:during low river flow)
The ammonia nitrogen objective at least 5 weekly samples
is taken
an average of at least 5 weekly samples
T:in a period of 30 days T:during low river flow