NAC445A.250. Monitoring.

     1. Any discharge authorized by a permit may be subject to such monitoring requirements as may be reasonably required by the Director including the installation, use and maintenance of monitoring equipment or methods, including, where appropriate, biological monitoring methods.

     2. Any discharge authorized by a permit which:

     (a) Is not a minor discharge; or

     (b) The Regional Administrator requests, in writing, be monitored,

Ê must be monitored.

     3. Any discharge authorized by an NPDES permit which contains toxic pollutants for which an effluent standard has been established by the Regional Administrator pursuant to section 307(a) of the Act, must be monitored by the holder of the permit for at least the following:

     (a) Flow, in gallons per day; and

     (b) All of the following pollutants:

          (1) Pollutants either directly or indirectly through the use of accepted correlation coefficients or equivalent measurement which are subject to reduction or elimination under the terms and conditions of the permit;

          (2) Pollutants which the Director finds, on the basis of information available to him or her, could have a significant impact on the quality of the waters of the State;

          (3) Pollutants specified by the Administrator, in regulations issued pursuant to the Act, as subject to monitoring as a requirement of an NPDES permit; and

          (4) Any pollutants in addition to the above which the Regional Administrator requests, in writing, be monitored as a requirement of an NPDES permit.

     4. Each effluent flow or pollutant required to be monitored pursuant to this subsection must be monitored at intervals sufficiently frequent to yield data which reasonably characterize the nature of the discharge of the monitored effluent flow or pollutant. Variable effluent flows and pollutant levels may be monitored at more frequent intervals than relatively constant effluent flows and pollutant levels.

     [Environmental Comm’n, Water Pollution Control Reg. §§ 7.1.1-7.1.3, eff. 2-26-75]—(NAC A by R020-99, 9-27-99)