A groundwater monitoring plan shall be implemented, to be carried out over a period of time commencing upon completion of remedial actions taken to comply with the standards in Sec. 192.02, and of a duration which is adequate to demonstrate that future performance of the system of disposal can reasonably be expected to be in accordance with the design requirements of Sec. 192.02(c). This plan and the length of the monitoring period shall be modified to incorporate any corrective actions required under Sec. 192.04 or Sec. 192.12(c). [60 FR 2866, Jan. 11, 1995]