NAC444.7484. Program for sampling and analysis.

     1. The owner or operator shall notify the solid waste management authority that the documentation of the program for sampling and analysis has been placed in the records of the disposal site.

     2. A system for monitoring groundwater must include:

     (a) Consistent sampling and analytical procedures designed to ensure monitoring results which provide an accurate representation of the quality of the background and downgradient groundwater at the monitoring wells installed in compliance with NAC 444.7483.

     (b) Procedures and techniques for:

          (1) The collection, preservation and shipment of samples;

          (2) Analyzing samples;

          (3) The control of the chain of custody; and

          (4) Quality assurance and quality control.

     (c) Methods for sampling and analysis which are appropriate for sampling groundwater and which accurately measure hazardous constituents and other monitoring parameters in samples of groundwater. Samples of groundwater must not be filtered in the field before they are analyzed in the laboratory.

     3. The sampling procedures and frequency must be protective of public health and safety and the environment.

     4. Each time groundwater is sampled, the elevations of groundwater must be measured in each well immediately before purging and the owner or operator shall determine the rate and direction of the flow of groundwater. The elevations of groundwater in wells which monitor the same disposal site must be measured within a period that is short enough to avoid temporal variations in the flow of groundwater which could preclude an accurate determination of the rate of flow and direction of groundwater.

     5. The owner or operator shall determine the quality of the background groundwater in a hydraulically upgradient or background well for each of the monitoring parameters or constituents required by the system for monitoring groundwater which applies to the municipal solid waste landfill unit, as determined pursuant to NAC 444.7487 or 444.749. The quality of the background groundwater may be determined at wells that are not located hydraulically upgradient from the municipal solid waste landfill unit if the monitoring system meets the requirements of NAC 444.7483.

     6. The number of samples collected to establish data concerning the quality of groundwater must be consistent with the appropriate statistical procedures set forth in NAC 444.7485. The sampling procedures used must be those specified by NAC 444.7488 for detection monitoring, NAC 444.749 for assessment monitoring and NAC 444.7493 for corrective action.

     (Added to NAC by Environmental Comm’n, eff. 11-8-93)