Construction Access & Installation Agreement – Parsons Environment & Infrastructure Group Inc.

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-5- EXHIBIT B Guidance from IDEM Technical Staff for Installation The Indiana Brownfields Program and IDEM Technical staff have reviewed the proposed construction of the biofilter and associated piping for a methane treatment pilot project, as submitted September 25, 2023 (VFC #83536075 [ecm.idem.in.gov]). The following is recommended during and after installation of the methane treatment biofilter: (1) The proposed design indicates that the landfill cover will not be disturbed, because the biofilter will be constructed on top of the cover. IDEM reiterates that the landfill’s two feet of clay cap AND six inches of topsoil should not be excavated or disturbed during installation of the biofilter. All topsoil referenced in project documents needs to be moved on to the landfill without the use of large trucks traversing the cap, due to the potential for cap damage from oversized vehicles. (2) The biofilter design proposes to divert a slipstream of gas to the biofilter, while leaving the existing gas collection lines and gas extraction system intact and active, as originally designed. The biofilter design includes a return line for treated gas to the blower/flare system after passing through the biofilter. IDEM notes that construction of the return line is crucial to prevent a build-up of methane gas. (3) The biofilter needs to be maintained and in good condition during the lifetime of its use. IDEM requires repair of the cover and equipment if disturbed/damaged during the biofilter installation and operation and return of the facility back to the pre-biofilter condition upon completion of the project. (4) Applicable requirements of 329 IAC 10-23-3 need to be followed.”