Storm Water Pollution Prevention Plan Development

1. Storm Water Pollution Prevention Plan Development Todd E. Hubmer PEWSB & Associateshubmer@wsbeng.com

2. How to develop a SWPPP • Description of the project • Description of how storm water and erosion will be manage on-site • Includes narrative, erosion control plan sheets, standard details • Drainage map, soils map, ponding calcs

3. SWPPP Components • Ponding must treat 0.5” of runoff from new impervious surface for entire subwatershed • Wet basin, • Regional pond, • Combination, or • Alternative method (rain garden, etc.; requires 90 day review by MPCA) • Road projects: fit in ponding if you can. If cannot fit in, other options (grassy swales, rock checks grit chambers, etc.) should be used

4. Inspections and Maintenance • NPDES requires inspection • Every 7 days • Within 24 hours of a 0.5 inch-24 hour rainfall event • Once a month for areas that have undergone final stabilization (but work is ongoing in other areas) • See PCA calendar

5. Inspections and Maintenance • Inspection and maintenance must be recorded in writing and include: • Date and time • Name of inspector • Findings and recommendations • Corrective actions taken • Date and amount of rainfall >0.5” in 24 hrs • Documentation of changes in SWPPP

6. Penalties/Enforcement • PCA will be increasing enforcement • SWCD’s, Watershed Districts can be authorized agents for PCA • You will need to produce the SWPPP and inspection reports • Penalty for non-conformance is $10,000 per day per violation Erosion Control Jail

7. Erosion Control BMP’sRequired by NPDES

8. INLET PROTECTION

9. MAINTENANCE OF SILT FENCE OR IF ADDITIONAL BMP’S MAY BE REQUIRED GEOTEXTILE FABRIC

10. ROCK CONSTRUCTION ENTRANCE TO REDUCE SEDIMENT TRACKED OFF SITE

11. FINAL STABILIZATION

12. DESIGNATED WASH-OUT SITE

13. AFTER CATEGORY 1 BLANKET, TEMPORARY SEED, AND SILT FENCE MAINTENANCE

14. Sediment tracked off site or on streets must be removed with 24 hours

15. Silt fence repaired, replaced when down or sediment reaches 1/3 height of fence w/i 24 hours

16. Other NPDES requirements • Silt fence repaired, replaced when down or sed reaches 1/3 height of fence w/i 24 hours • Temp and perm basins must be drained and cleaned out when ½ storage volume is gone w/i 72 hours • Sed deltas, filled CB’s, filled ditches must be cleaned/stabilized w/i 7 days • Sed tracked off site must be removed with 24 hours

17. Other NPDES requirements • If sed in lakes, wetlands, streams, stabilize area upstream and remove sed w/i 7 days • Hazardous materials stored appropriately • No dumping of oil, junk, etc • Garbage must be disposed of properly • Once site has undergone final stabilization, NOT submitted

18. Other inspection requirements • Seeding timeline w/i 200 feet of surface water • Slope steeper than 3:1 – 7 days • Slope 10:1 to 3:1 – 14 days • Slope flatter than 10:1 – 21 days • Surface water is stream, lake, wetland, ditches, ponds, whether natural or artificial. • Stockpiles need silt fence • Riprap at pipe ends w/i 24 hours of connecting • Dewatering – Water must be directed to storm water pond or treated before discharge

19. Questions?