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Page 15 of 38 Permit No: MNR040000 5. Post -Construction Stormwater Management New permittees shall develop, implement, and enforce, and existing permittees shall revise their current program, as necessary, and continue to implement and enforce, a Post - Construction Stormwater Management program that prevents or reduces water pollution after construction activity is completed, related to new development and redevelopment projects with land disturbance of greater than or equal to one acre, including projects less than one acre that are part of a larger common plan of development or sale, within the permittee's jurisdiction and that discharge to the permittee's small MS4. The program shall consist, at a minimum, of the following: a. A Regulatory Mechanism(s) that incorporates: (1) A requirement that owners and/or operators of construction activity submit site plans with post -construction stormwater management BMPs to the permittee for review and approval, prior to start of construction activity (2) Conditions for Post -Construction Stormwater Management: The permittee shall develop and implement a Post -Construction Stormwater Management program that requires the use of any combination of BMPs, with highest preference given to Green Infrastructure techniques and practices (e.g., infiltration, evapotranspiration, reuse/harvesting, conservation design, urban forestry, green roofs, etc.), necessary to meet the following conditions on the site of a construction activity to the MEP: (a) For new development projects — no net increase from pre -project conditions (on an annual average basis) of: 1) Stormwater discharge Volume, unless precluded by the stormwater management limitations in Part III.D.5.a(3)(a) 2) Stormwater discharges of Total Suspended Solids (TSS) 3) Stormwater discharges of Total Phosphorus (TP) (b) For redevelopment projects —a net reduction from pre -project conditions (on an annual average basis) of: 1) Stormwater discharge Volume, unless precluded by the stormwater management limitations in Part III.D.5.a(3)(a) 2) Stormwater discharges of TSS 3) Stormwater discharges of TP (3) Stormwater management limitations and exceptions (a) Limitations 1) The permittee's Regulatory Mechanism (s) shall prohibit the use of infiltration techniques to achieve the conditions for post -construction stormwater management in Part III.D.5.a(2) when the infiltration structural stormwater BMP will receive discharges from, or be constructed in areas: