Stormwater Infiltration Concerns on Brownfields Rebecca A. Bourdon, - PowerPoint PPT Presentation

Stormwater Infiltration Concerns on Brownfields Rebecca A. Bourdon, PG Hydrogeologist Remediation Division 9.13.12

Stormwater Infiltration Concept MEETS

Brownfields Programs  Assurances: • Expedited Review, No Further Action, Response Action Plan Approval, etc.  Developer Liability  Snapshot-in-Time plus Development Plan

Contaminant Distribution: • Snapshot in Time • Closure Based on Current Use • Response Actions for Risks

PBP/VIC Current Procedures: • Process/evaluate on a site- specific basis • Dependent on communication between consulting engineers, environmental professionals and regulatory body • Information gaps easily occur

PBP/VIC Future Procedures: • EPA guidance and PBP/VIC-specific guidance language will shape future requirements • Design options – BMPs, design for spatial occurrence, information gathering, additional investigation

Information Needs Existing COC occurrence Site Conceptual Model Upgradient and downgradient sites Existing COCs Life of Stormwater System Design capacity O&M Life cycle costs per COC presence or mitigation Hydrologic Alterations Modeling Mounding Karst/Conduit flow Improving natural attenuation conditions

• Plan for stormwater infiltration information needs with contamination investigation work (Phase I) • Communicate in design Contact: PBP – Rebecca Bourdon phase, reporting phase and 651.757.2240 rebecca.bourdon@state.mn.us implementation phase VIC – Lynn Grigor 651.757.2399 lynn.grigor@state.mn.us • Anticipate questions