Stormwater Management Regulatory Update April 27 | 2010 Idaho Transportation Department Project Development Conference Presented by: Steve Burgos, Brown and Caldwell

ITD PROJECT DEVELOPMENT CONFERENCE Regulatory Updates: New Proposed Construction General Permit: Sneak Preview EPA Guidance on Stormwater and TMDLs MS4 Permits and Impacts of New Guidance ITD’s Initiatives to Address New Requirements Questions Agenda 2

ITD PROJECT DEVELOPMENT CONFERENCE Refresher: Federal Permits for Stormwater Pollution Control Clean Water Act National Pollutant Discharge Elimination System (NPDES) Construction General Permit (CGP) ConstructionIndustrial Multi-Sector General Permit (MSGP) Municipal Municipal Separate Storm Sewer Systems (MS4) Storm Water Management

ITD PROJECT DEVELOPMENT CONFERENCE Proposed CGP is Here! 4 Released April 15, day comment period Final CGP by January 31, 2012 Current CGP is scheduled to expire on June 30, 2011 EPA is proposing extension to current permit through January 31, 2012

ITD PROJECT DEVELOPMENT CONFERENCE Required use of electronic Notice of Intent process; Sediment and erosion controls; Natural buffers or alternative controls; Soil stabilization; Pollution prevention; Site inspections; and Permit termination Proposed CGP Contains New Requirements for: 5 Generally, the proposed permit is more prescriptive and refines requirements to specific values and/or expectations

ITD PROJECT DEVELOPMENT CONFERENCE EPA proposes to increase “waiting period” from 7 days to 30 days for “new sources” New 30-day timeframe accommodates endangered species and historic properties-related reviews Authorization Process / NOIs 6 EPA proposes to maximize use of electronic NOI Potentially requiring operators seek coverage using eNOI system

ITD PROJECT DEVELOPMENT CONFERENCE Buffers – “Operators must ensure that, if any waters of the U.S. are located on or immediately adjacent to the site, any discharges flowing through the area between the disturbed portion of the site and the waters of the United States are treated by an area of undisturbed natural vegetation that alone or with alternative sediment and erosion controls achieves a reduction in sediment loads equivalent to a 50 foot buffer.” Sediment and Erosion Controls Requirements 7

ITD PROJECT DEVELOPMENT CONFERENCE Installation of Controls Prior to Construction: Operators must install and make operational all sediment and erosion controls prior to conducting earth-disturbing activities in any portion of the site, with certain exceptions Sediment and Erosion Control Requirements 8 Entrance and Exit Points: Any entrance and exit points created on the site must be stabilized for a minimum of 50 feet into the site

ITD PROJECT DEVELOPMENT CONFERENCE Permit includes modified stabilization requirements that define more specifically what EPA expects for temporary and final stabilization Criteria are proposed for both vegetative and non-vegetative stabilization Based on the Revised Universal Soil Loss Equation’s (RUSLE) cover management factor, or “C-factor” (erosion control effectiveness) Vegetative: C < 0.05 Non vegetative: C 15% Appendix H provides common C-Factors for specific BMPs Stabilization Requirements 9

ITD PROJECT DEVELOPMENT CONFERENCE Permit includes specific requirements and design standards Install secondary containment or cover activities Inspect all construction vehicles once per week Plastic covering for exposed construction materials Pollution Prevention 10

ITD PROJECT DEVELOPMENT CONFERENCE Numeric Effluent Limits Original proposal: Beginning 8/1/11, effluent limit of 280 NTU will apply to discharges from sites disturbing 20+ acres Beginning 2/2/14, effluent limit of 280 NTU will apply to discharges from sites disturbing 10+ acres

ITD PROJECT DEVELOPMENT CONFERENCE Why are NELs being delayed? National Association of Home Builders (NAHB) filed a challenge to proposed NELs Contested legality of a numeric limit Reminder: Stormwater NPDES Permits typically require management to “Maximum Extent Practicable”

ITD PROJECT DEVELOPMENT CONFERENCE Current Status on NELs After considering issues raised by NAHB EPA filed motion asking Court to vacate numeric limit Remand that portion of the rules back to EPA for reconsideration "Based on EPA's examination of the dataset underlying the 280-NTU limit it adopted, the Agency has concluded that it improperly interpreted the data and, as a result, the calculations in the existing administrative record are no longer adequate to support the 280-NTU effluent limit. EPA therefore wishes to re-examine that number through a narrowly-tailored notice-and- comment rulemaking and, if necessary, revise that portion of the limit before proceeding with its defense of the rule."

ITD PROJECT DEVELOPMENT CONFERENCE Only included as placeholder NEL’s not Included in Proposed CGP 14

ITD PROJECT DEVELOPMENT CONFERENCE For sites discharging to waters impaired for common pollutants associated with construction activities, such as sediment and nutrients Tighter stabilization deadlines (immediately initiate stabilization if construction in an area is inactive for 7 days, as opposed to 14 days) More frequent site inspections (once per week, daily visual inspections) For sites disturbing 10 or more acres at a time, conduct benchmark monitoring of discharge based on receiving water’s water quality criterion Permit also proposes to include additional requirements for waters designated as Tier 2, Tier 2.5, or Tier 3 waters Water Quality-Based Effluent Limits 15

ITD PROJECT DEVELOPMENT CONFERENCE On Friday April 15, IDEQ submitted final Antidegradation Rule Package to EPA for review and approval The Antidegradation Implementation Procedures require three tiers of review for new or expanded NPDES permits Tier I waters (about 2/3 of the permitted discharges statewide) will require review to ensure compliance with water quality standards. Tier II waters (about 1/3 of the permitted discharges statewide), a social and economic analysis justifying the new or expanded discharge. Tier III waters, currently no waters in the state, are not allowed increases from new or existing sources. The final rule can be viewed at: Idaho Anti-Degradation Rule Update 16

ITD PROJECT DEVELOPMENT CONFERENCE If site inspection occurs during discharge-generating rain event EPA proposes to require operators visually assess quality of discharge Inspect for color, odor, floating, settled, or suspended solids Site Inspections 17

ITD PROJECT DEVELOPMENT CONFERENCE Current permit requires corrective action Proposed permit includes specific triggering conditions for corrective action as well as deadlines to fix such problems and document what was done Initiate work to fix the problem immediately after discovery and complete such work by close of next full work day If new BMPs required, 7 day window to install Corrective Actions 18

ITD PROJECT DEVELOPMENT CONFERENCE EPA proposes to include additional requirements that affect when a site may terminate coverage Removal of all temporary stormwater controls Removal of all construction materials, waste, and waste handling devices Notice of Termination 19

ITD PROJECT DEVELOPMENT CONFERENCE Proposed CGP: Questions? Brown and Caldwell 20

EPA Guidance on Stormwater and TMDLs 21

ITD PROJECT DEVELOPMENT CONFERENCE Update to 2002 guidance Four major revisions: 1.Numeric water quality based effluent limitations in stormwater NPDES permits 2.Disaggregating stormwater sources in a WLA 3.Using surrogates to establish TMDL loading capacity 4.Treating load allocations as wasteload allocations 11/12/10 EPA Guidance on Stormwater

ITD PROJECT DEVELOPMENT CONFERENCE Reminder: Clean Water Act Objective “Restore and Maintain the Chemical, Physical, and Biological Integrity of the Nations Waters”

ITD PROJECT DEVELOPMENT CONFERENCE Reminder: TMDLs Focused on Achieving Clean Water Act Goals Instream Criteria TMDLs NPDES Limits Other Control Strategies For example: Offsets, BMPs Use Classification Clean Water Act Goal: “Restore and Maintain the Chemical, Physical, and Biological Integrity of the Nations Waters” (d) Listing (if impairment) 3

ITD PROJECT DEVELOPMENT CONFERENCE Create “objective and accountable means for managing stormwater” Future permits will be written with numeric limits for impairments Most likely tied to TMDL and wasteload allocations assigned to stormwater discharges 1. Numeric Water Quality Based Effluent Limitations in Stormwater NPDES Permits... So What? 25 NOTE: If under an NPDES permit, stormwater is considered a ‘point source’

ITD PROJECT DEVELOPMENT CONFERENCE Traditionally, stormwater given aggregate WLA in TMDLs met through BMPs managed to the ‘Maximum Extent Practicable’ In future, stormwater will be divided into separate sources much like wastewater NPDES permits are assigned to specific WWTP: E.g., ITD District X will be given a stormwater WLA E.g., City of Boise will be given a stormwater WLA Etc. Key question: If point source WWTP are facing stringent limits, what about stormwater? 2. Disaggregating Stormwater Sources in a WLA... So What? 26

ITD PROJECT DEVELOPMENT CONFERENCE 3. Using Surrogates to Establish TMDL Loading Capacity... So What? 27 Often, there is not enough stormwater data to establish relevant wasteload allocations for stormwater sources New TMDLs are using surrogates in lieu of actual water quality data

ITD PROJECT DEVELOPMENT CONFERENCE For stormwater discharges not currently regulated under NPDES Load allocation assigned should include language that the load allocation will transition to a wasteload allocation once the discharge is permitted EX: For TMDLs where MS4 permits are pending (Twin Falls, Moscow, others) 4.Treating Load Allocations as Wasteload Allocations... So what? 28

ITD PROJECT DEVELOPMENT CONFERENCE Example: Lower Boise River TMDL

ITD PROJECT DEVELOPMENT CONFERENCE Lower Boise River TMDL Boise River Pollutant Issues Impairments Bacteria Sediment Temperature Nutrients Mercury Sources Treated wastewater Stormwater Agriculture

ITD PROJECT DEVELOPMENT CONFERENCE Impacts on Treasure Valley MS4 Permittees As TMDL revised, WLA for stormwater is likely for key pollutants MS4s impacted ITD District 3 (Ada and Canyon Co.) ACHD City of Boise City of Nampa City of Caldwell City of Middleton Nampa Highway District Others Boise Nampa-Caldwell Pocatello Idaho Falls Lewiston Coeur D’Alene MS4 Urbanized Areas In Idaho

ITD PROJECT DEVELOPMENT CONFERENCE Stormwater Management Guide Standardized policies and procedures for CGP, MSGP, and MS4 compliance Revised standard erosion and sediment control drawings awings.htm awings.htm ITD SWPPP Template Designer Stormwater Training Revised and updated BMP Manual Coming in 2011 ITD Initiatives to Address Coming Changes 32

Stormwater Management Regulatory Update April 27 | 2010 Idaho Transportation Department Project Development Conference Presented by: Steve Burgos, Brown and Caldwell