1. CHRP/Managers Meeting October 2009 Angelo Liberti, Chief Surface Water Protection Office of Water Resources 401.222.4700 ext 7225 angelo.liberti@dem.ri.gov

2. NBC CSO Project Phase I tunnel - operational Nov 2008 Post storm monitoring Re-assess Rainfall Closure Criteria Phase II - preliminary design completed

3. Current Plan for Managing Nutrients From WWTF 50% Reduction from RI WWTFs –DEM permits issued – June 2005 Comparable reductions from MA WWTFs

4. Revised WWTF Nitrogen Limits 5 mg/l –UBWPAD –Woonsocket (3 mg/l) –NBC-Fields Pt. –NBC Bucklin Pt. –East Greenwich –No. Attleborough –Attleboro –Grafton –Uxbridge –Northbridge –(max extent) Limits May – October, require operation of treatment to remove N to max extent possible November-April –East Providence –Cranston –West Warwick –Warwick –Smithfield (10 mg/l) –Burrillville (max extent) - Warren – anticipated to address impacts to the Palmer River 8 mg/l

5. Current Status of Load Reduction Efforts 8 - WWTFs have complete upgrades (2 require additional modifications) 1 - Under construction NBC Fields Point (completion by 12/31/2013) 1 – Planning Underway Woonsocket (Plan was due 8/09, construction by 3/2014) 2 - Design Underway NBC Bucklin Point East Providence (due 6/01/10, construction by 9/2012 Approximately 30% reduction in RI WWTF load achieved in 2005. Next significant reduction May 2014

6. Status of Compliance with Revised Permit limits for N MA WWTFs North Attleborough 8 mg/lEPA issued 2/08; appeals settled (complete construction late 2012) Attleboro 8 mg/lEPA issued 6/08; Permit upheld on appeal. EAB decision issued 9/15/09. Upper Blackstone (UBWPAD) 5 mg/lEPA issued 8/08; appeals filed. Oral arguments before EAB 10/29/09 Grafton 8 mg/lNo action to date Uxbridge 8 mg/lNo action to date Northbridge NAEPA issued 9/06; reduce N to max extent

7. Status of Compliance with Revised Permit limits for N RI WWTFs LimitStatusAve TN (mg/l) 5/07-8/08 Cranston 8 mg/lConstruction comp. –1/2006. Additional modifications to achieve TP = 0.1 mg/l and consistently achieve TN May-Oct complete construction by 3/31/2013 8.2 Warwick 8 mg/lConstruction comp. -11/2004 Additional modifications to achieve TP = 0.1 mg/l and consistently achieve TN May-Oct 8.0 West Warwick 8 mg/lConstruction comp. -7/2005. Additional modifications to achieve TP = 0.1 mg/l 9.2 (7.5)* East Greenwich 5 mg/lConstruction comp.–3/20064.0 East Providence 8 mg/lFinal Design due 6/01/10 Construction Deadline 9/2012 12.3 NBC- Bucklin 5 mg/lInitial Construction Complete 2006 FP approval 10/09, NBC requested 1year 5 months for design. 7.5 * Excludes May data (19.5, 13 mg/l)

8. Status of Compliance with Revised Permit limits for N RI WWTFs (Cont.) LimitStatusAve TN (mg/l) 5/07-8/08 NBC -Field Pt 5 mg/lDesign Approved 09, Complete Construction 12/31/2013 13.7 Woonsocket 5 mg/lConstruction Comp. 2002 Agreed to complete construction for 3 mg/l by 3/2014 6.7 Burrillville Max extent TN Reductions since 200210.5 (7.7)* Smithfield 10 mg/lConstruction comp. -6/2006. Additional changes to consistently meet TP April-Oct 8.3 Warren Anticipated that Warren will need to reduce N to address impacts to the Palmer River 17.7 Westerly Construction comp. 10/036.3

11. Nitrogen Reduction Projections Nitrogen removal at 11 RI WWTFs - reduces their summer season nitrogen loading by 65%, dropping to 48% as WWTF flows reach approved design flows.

12. Comparison of MERL Experiments to Providence/Seekonk System

13. Allowable Loading Condition

14. Table 4: Approved WWTF design flows and design flows used for the load evaluations. Evaluation of WWTF Load Reductions

15. Loading Condition Vs. WWTF Load Reductions

17. Loading Condition Vs. Cost

18. Anticipated RI WWTF Load Reductions

19. Average Chlorophyll vs N Load y = 0.62 x + 6.32 R 2 = 0.94 0 10 20 30 40 50 60 70 0102030405060708090100 Nitrogen Load (mmol/m 2 /d) Chlorophyll a (ug/l) 32 X 16 X 8 X 4 X 2 X 1 X C Allowable Loading Condition