Section 40.0998 - Engineered Barriers(1) An Engineered B arrier means a permanent cap with or without a liner that is designed, constructed and maintained in accordance with scientific and engineering standards to achieve a level of no significant risk for any foreseeable period of time.(2) An Engineered Barrier shall: (a) prevent direct contact with contaminated media;(b) control any vapors or dust emanating from contaminated media;(c) prevent erosion and any infiltration of precipitation or run-off that could jeopardize the integrity of the barrier or result in the potential mobilization and migration of contaminants;(d) be comprised of materials that are resistant to degradation;(e) be consistent with the technical standards of RCRA Subpart N, 40 CFR 264.300, 310 CMR 30.600: Technical Standards for All Hazardous Waste Facilities or equivalent standards;(f) include a defining layer that visually identifies the beginning of the barrier; and(g) be appropriately monitored and maintained to ensure the long-term integrity and performance in accordance with a monitoring and maintenance plan; such plan shall be submitted to the Department and shall document that one or more financial assurance mechanism(s) as specified at 310 CMR 40.0998(4) have been established which adequately provide for ongoing future monitoring, maintenance and any necessary repair or replacement of the barrier.(3) An Engineered Barrier shall not include an existing building, structure or cover material unless it is designed and constructed to serve as an Engineered Barrier pursuant to the requirements of 310 CMR 40.0998.(4) A financial assurance mechanism required for the implementation of an Engineered Barrier shall: (a) for any state agency, state authority or municipality, either be consistent with the specifications in 310 CMR 30.906: Financial Assurance for Post-closure Care or consist of an agreement executed between such agency or authority and the Department that documents such agency's, authority's, or municipality's commitment to the ongoing future monitoring, maintenance, and if necessary, the timely repair and replacement of the Engineered Barrier; and(b) for any other person, be consistent with the specifications in 310 CMR 30.906: Financial Assurance for Post-closure Care.(5) Pursuant to 310 CMR 40.0414(7), 310 CMR 40.0442(4), and 310 CMR 40.0859(4), an Engineered Barrier shall not be implemented as part of a Permanent Solution unless and until a Phase III feasibility evaluation has been conducted pursuant to 310 CMR 40.0850 and such evaluation demonstrates the lack of a feasible alternative.Adopted by Mass Register Issue 1503, eff. 3/1/2024.Amended by Mass Register Issue S1516, eff. 3/1/2024.