SWPPP Development. What are Storm Water Pollution Prevention Plans. Jerald S. Fifield, Ph.D., CISEC HydroDynamics Incorporated Parker, CO

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1 What are Storm Water Pollution Prevention Plans S&EC PLANS (DRAWINGS) PROJECT SITE NARRATIVE Jerald S. Fifield, Ph.D., CISEC HydroDynamics Incorporated Parker, CO SWPPP SWPPP Development Section 7 of (Hawaii Administrative Rules) HAR-55-C Requirement Develop prior to submitting the Notice of Intent (NOI) Contents Narrative Drawings 1

2 What does the acronym NPDES mean? 1. National Pollution Discharge Environmental 2. National Pollutant Discharge Elimination 3. National Pollution Discharge Elimination 4. National Pollutant Discharge Environmental Updates will occur by December 6, 2018 based upon the 2017 Construction General Permit (CGP) disturbance 1.0-acre disturbance < 1.0-acre when part of a larger development A permit is required to discharge stormwater Updates will occur by December 6, 2018 based upon the 2017 Construction General Permit (CGP) disturbance 1.0-acre disturbance < 1.0-acre when part of a larger development A permit is required to discharge stormwater General Permit Does not Address Discharges in or to state waters classified by the department as "class 1, Inland Waters," "class AA, Marine Waters," and areas restricted in accordance with the State's "No Discharge" policy in chapter entitled "Water Quality Standards." 2

3 What is Chapter (Water Quality Standards)? Limitations on Permit Does not cover storm water discharges From construction sites Flowing into a sanitary sewer system Containing Flocculants and other treatment chemicals Entering a separate storm water drainage system unless Written approval is granted Permittee is the owner From 404 Permitted areas From clearing of agricultural lands Which the (EPA) director Has issued through another general permit Finds should be under an individual permit From new sources that cause or contribute to the departure of any applicable water quality standard Area of Disturbance The permittee is required to minimize the amount of soil exposed during construction activities. The permittee is also subject to the deadlines for temporarily and/or permanently stabilizing exposed portions of the site pursuant to section Stabilization If permanent Immediately Complete as soon as practical but no later than the end of the next day If temporary for 14 or more days Immediately Completion by 14 calendar days after initiation of soil stabilization measures 3

4 Area of Disturbance The permittee is required to minimize the amount of soil exposed during construction activities. The permittee is also subject to the deadlines for temporarily and/or permanently stabilizing exposed portions of the site pursuant to section 5.2. What is in the 2017 CGP? Cumulative earth disturbances cannot exceed 5 acres Land disturbance 5 acres If permanent or to be temporary for 14+ days, initiate immediately Complete ASAP or by 14 days Land disturbance > 5 acres If permanent or to be temporary for 14+ days, initiate immediately Complete ASAP or by 7 days Final Stabilization Criteria Uniform, perennial vegetation provides 70 percent or more of the native cover Non-vegetative stabilization measures provide effective cover Design Permittee shall account for: Identifying expected amount, frequency, intensity and duration of precipitation East side is humid/tropical West side is semi-arid Months of higher risks of being impacted by rainfall Months of lower risks of being impacted by rainfall Months of higher risks of being impacted by rainfall Design Permittee shall account for: Identifying expected amount, frequency, intensity and duration of precipitation Identifying the nature of storm water runoff and run-on Impervious surfaces, slopes and site drainage features Identify the range of site soil particles sizes Understand the type of soils that exist Discharge storm water onto vegetative areas Installation Permittee shall be responsible for Installing BMPs prior to earth-disturbance activities Installing BMPs in a correct manner Inspecting and maintaining BMPs Installing new BMPs as needed 4

5 Applicable to all Sites Provide natural buffers and sediment control Section State waters are within 50 feet of site Install perimeter controls Section Sediment control Non-Linear Project: Downstream of disturbed areas Linear Project: Where practicable and document in SWPPP Maintenance Remove sediment before 50% of barrier height Minimize sediment track-out Section Restrict vehicle traffic to designated exit points Sediment removal before exit onto paved roads Track-out removed by end of same work day or End of next work day if occurs during non-working hours Stockpiles Section Separate from storm water controls Protect from storm water flows (including run-on) Where practical, provide cover or temporary stabilization No discharge into any stormwater conveyance system Unless into a sediment containment system Minimize dust Section Apply water or use other Minimize disturbance of steep slopes Section % or steeper Preserve topsoil Section Permittee shall preserve Minimize soil compaction Section Final vegetation stabilization or infiltration Restrict vehicle and equipment use Use soil conditioning techniques Planting Protect storm drain inlets Section

6 Contaminated soil and/or stockpiles Section Prevent storm water from contacting Prevent the discharge of stormwater runoff Prevent: keep (something) from happening or arising Storm water cannot be in contact with contaminated soil or stockpile Storm water cannot discharge from the site Templet from EPA 6

7 In Summary, Development of a SWPPP Requires Documentation Permits Site conditions Other reports Assessing soils and hydrologic conditions Knowing limitations of BMPs Developing and adhering to time schedules Having and applying common sense Possessing political savvy Jerald S. Fifield, Ph.D., CISEC HydroDynamics Incorporated Parker, CO