567—112.21 (455B) Monitoring well maintenance and performance reevaluation plan.
	 112.21(1) A monitoring well maintenance and performance reevaluation plan shall be included as part of the hydrologic monitoring system plan. The plan shall ensure that all monitoring points remain reliable.
	 112.21(2) The plan shall provide for the following:
	  a.   	 A biennial examination of high and low water levels accompanied by a discussion of the acceptability of well location (vertically and horizontally) and exposure of the screened interval to the atmosphere.
	  b.   	 A biennial evaluation of water level conditions in the monitoring wells to ensure that the effects of waste disposal or well operation have not resulted in changes in the hydrologic setting and resultant flow paths.
	  c.   	 Annual measurements of well depths to ensure that wells are physically intact and not filling with sediment.
	  d.   	 Every five years conduct in-situ permeability tests on monitoring wells to compare test data with those collected originally to determine if well deterioration is occurring.