1. Blue Plains IMA Suburban Position February 22, 2007

2. Agenda Comments on DCWASA December 19, 2006 Presentation Suburban Position: –Capacity Allocation –ENR Cost Allocation –LTCP Cost Allocation

3. Analysis of Separate Systems Based on May 1989 Storm (Slides 3&4, Dec. 19, 2006, DCWASA Presentation) Illustrates the benefit of Suburban User capacity at BP to DC: –For the “separate system” DC would have to build bigger tunnels (205 mg vs 194 mg) for DC flows alone, DC would be funding 100% –For the “collective system” Only 194 mg of storage would be required Costs would be shared

4. Analysis of Separate Systems Based on May 1989 Storm (Slides 3&4, Dec. 19, 2006, DCWASA Presentation) Illustrates the benefit of Suburban capacity at BP to DC Tunnel Size for DC Only = 205 mg = 269 mg volume exceeding treatment capacity minus 64 mg allowable CSO

5. Analysis of Separate Systems Based on May 1989 Storm (Slides 3&4, Dec. 19, 2006, DCWASA Presentation) Illustrates the benefit of Suburban capacity at BP to DC Separate System Tunnel Size for DC Only = 205 mg = 269 mg volume exceeding treatment capacity minus 64 mg allowable CSO Collective System Tunnel Size for DC & Suburbs = 194 mg

6. Analysis of Separate Systems Based on May 1989 Storm (Slides 3&4, Dec. 19, 2006, DCWASA Presentation) Suburban Users rarely convey flow to BP within 4 hours PF = 2.0. Almost all excess flow in the separate system analysis occurred after PF declined to 1.38. DC benefits from full flow capacity at BP, paid for in part by suburban users.

7. Comments on DC WASA Model Runs and December 19, 2006 Presentation Three-year model simulation seems to be representative of collective system’s complex hydraulics. Cost share options favored by DC WASA do not reflect their own model analysis: –LTCP tunnel facilities for DC alone would be larger without capacity in BP and pump stations that suburban users have already paid for (slide 3 – 12/19/06) –size increase of LTCP tunnel facilities due to suburban user flows is 6 percent (slide 4 – 10/31/06, slide 6 – 12/19/06) –LTCP facilities handle up to 7.1 percent additional CSO on an annual average basis, which is viewed by suburbs as an upper bound on their O&M costs for the LTCP (slide 4 – 10/31/06)

8. Comments on DC WASA Model Runs and December 19, 2006 Presentation Clarifications needed: –Why is tunnel volume for “collective system” now = 194 mg? (Dec. 19, 2006, slides 4 and 5) Oct. 31, 2006 presentation showed 183 mg (slide 4) –DC’s capacity is assumed = 158 mgd. This should be 152.5 mgd (148 + 4.5 unallocated PI) –Difference in annual CSO volume should be = 7.1% (slide 4, 10/31/06), not 9.4% as shown in slide 6.

9. Comments on DC WASA Model Runs and December 19, 2006 Presentation Clarifications needed: –ECF for Alternative C-1 is shown as a Joint Use Facility (521 mgd) with flow split based on 370 mgd: Split should be based on increment above 336 mgd: DC = 336 mgd plus split of 185 mgd based on share of Outfall 002 Suburbs = split of 185 mgd based on share of Outfall 002

10. Agenda Comments on DCWASA December 19, 2007 Presentation Suburban Position: –Capacity Allocation –ENR Cost Allocation –LTCP Cost Allocation

11. Suburban Position Capacity Allocation DC needs to purchase additional treatment capacity in order to meet its present and near-term needs. User1985 IMA / Present BPSA 2030 / COG 6.3 Suburban Position DC148.0171.7162.5 WSSC169.6149.7154.6 Fairfax Co31.0 36.0 LCSA13.8 Reserve4.500 Other PI3.13.53.1 Total370369.7370

13. Suburban Position Capacity Cost Allocation All users need to have adequate capacity to handle average annual flows through full treatment * ENR Cost Allocation will be in proportion to IMA capacity allocation No further sales or transfers of treatment capacity to non-IMA signatories. WSSC to be compensated for equity investment of transferred capacity. WSSC to be compensated for past use of its capacity by others. * Suburban users understand that treatment of “Captured/Combined” flows is being negotiated with EPA

14. Suburban Position Capacity Cost Allocation Capacity in Outfall 002 is shared in proportion to treatment allocation. Capacity in Outfall 001 (521 mgd in ECF) is shared for increment above 336 mgd: –DC Share = 336 mgd + 185 mgd x 162.5/370 –WSSC Share = 185 x 154.6/370 –Fairfax Share = 185 x 36.0/370 Users’ O&M costs for treatment to be flow-proportional for the capacity in Outfall 002 (per IMA) and for the capacity in Outfall 001 (per ECF share)

15. Suburban Position LTCP Cost Allocation Suburban Users will participate in capital costs of tunnels, net of Federal funding, in proportion to tunnel volume Suburban Users will participate in O&M costs of tunnels in proportion to annual average overflow volume