Section 329 IAC 10-15-5 - Description of proposed ground water monitoring well systemAuthority: IC 13-14-8-7; IC 13-15; IC 13-19-3
Affected: IC 13-20; IC 36-9-30
Sec. 5.
(a) The hydrogeologic site investigation report that accompanies permit applications for new MSWLFs and lateral expansions must contain a description of the proposed ground water monitoring well system that, at a minimum, includes the following information:(1) Monitoring point locations, design, and installation procedures. Installation procedures must comply with 329 IAC 10-21-4.(2) A thorough evaluation of the suitability of any existing monitoring points proposed for inclusion in the ground water monitoring well system.(3) An explanation of how the proposed ground water monitoring well system addresses the hydrogeologic conditions identified within the uppermost aquifer system and any significant zones of saturation that exist above the uppermost aquifer system.(4) A description of how and where ground water monitoring wells will be installed at appropriate locations and depths, to yield ground water samples from the uppermost aquifer and any significant zones of saturation that exist above the uppermost aquifer system. Ground water samples must represent both the quality of background ground water that has not been affected by the proposed MSWLF unit and quality of ground water quality passing the monitoring boundary of the proposed MSWLF unit.(5) A description of how background ground water monitoring wells will monitor the same hydrologic units as the downgradient ground water monitoring wells.(6) If a single monitoring well cannot adequately intercept and monitor the vertical extent of a potential pathway of contaminant migration at a sampling location, a description of how a ground water monitoring well cluster will be installed.(7) For the uppermost aquifer system, a description of how ground water monitoring well spacing will not exceed five hundred (500) feet along the monitoring boundary of the proposed MSWLF unit. In geologically complex environments as determined by the commissioner, closer monitoring well spacing may be required. Alternate spacing of ground water monitoring wells may be approved by the commissioner based on particular site or facility conditions. Monitoring well spacing must provide at least two (2) background ground water monitoring wells and four (4) downgradient monitoring wells or well clusters within the uppermost aquifer system and any significant zones of saturation that exist above the uppermost aquifer system. An alternate number of background wells may be approved by the commissioner based on particular site or facility conditions.(b) The commissioner may consider an individual compliance ground water monitoring well system for intrawell statistical comparison methods if the permittee can demonstrate either of the following:(1) The uppermost aquifer system, and any significant zones of saturation that exist above the uppermost aquifer system are discontinuous.(2) Significant spatial variability exists within the aquifer.Solid Waste Management Board; 329 IAC 10-15-5; filed Mar 14, 1996, 5:00 p.m.: 19 IR 1823; filed Mar 19, 1998, 11:07 a.m.: 21 IR 2765; filed Aug 2, 1999, 11:50 a.m.: 22 IR 3804; filed Feb 9, 2004, 4:51 p.m.: 27 IR 1810, eff Apr 1, 2004