1. When required by the WRA Director pursuant to this division, each permitted user shall at its expense provide and operate monitoring facilities to allow inspection, sampling, and flow measurement of the building sewer or internal drainage systems. The WRA Director may require the placement of such monitoring facilities at the end of each process where pollutants are used, produced, or treated. The monitoring facility should normally be situated on the user’s premises and located so that it will not be obstructed by landscaping or parked vehicles.
2. When required by the wastewater discharge permit and within 90 days of written notification, a user shall install a sampling chamber for each separate discharge of the building sewer in accordance with plans and specification approved by the WRA Director. A user shall provide ample room in or near such sampling chamber to allow accurate sampling and preparation of samples for analysis. Each user shall at its expense maintain all sampling and measuring equipment in a safe and proper operating condition at all times, which equipment shall be safely, easily and independently accessible to authorized representatives of the WRA.
Users shall certify all flow measuring devices to be in proper working condition at a frequency specified in the permit or in writing by the WRA Director, using a qualified technician acceptable to the WRA Director. Sampling shall be in accordance with the following:
A. Each sampling chamber shall contain a flume unless another device is approved by the WRA Director, with a recording and totalizing device for measurement of the liquid quantity.
B. At the discretion of the WRA Director, metered water supply to a user may be used as the volume quantity where it is substantiated that the metered water supply and waste quantities are approximately the same, or where a measurable adjustment agreed to by the director is made in the metered water supply to determine the liquid waste quantity. Separate meters may be used to subtract water which is not discharged to the POTW or is discharged to a sewer other than the sampled location.
C. Samples shall be taken at a frequency and volume determined by the WRA Director and shall be properly refrigerated and preserved in accordance with Environmental Protection Agency approved methods. The sample shall be composited in proportion to the flow for a representative 24-hour sample. A time proportioned 24-hour sample may be used if flow proportioned sampling is determined by the WRA Director to be impractical. Grab samples shall be used where appropriate.
3. A user must inform the WRA Director prior to breaking a sampler seal, used by the WRA to detect sample tampering, unless necessary to prevent loss of life, personal injury, or severe property damage. A user shall not place additional seals or locks upon a sampler which may be used by the WRA without first obtaining approval from the WRA Director.