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Nutrient TMDLs and Their Effect on Dredging Operations in the Chesapeake Bay

Nutrient TMDLs and Their Effect on Dredging Operations in the Chesapeake Bay. William J Rue- EA Engineering, Science, & Technology, Inc. Nathaniel Brown- Maryland Port Administration George Harman- Phoenix Engineering, Inc. Kenna Oseroff- Maryland Environmental Service . Presenter Name.

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Nutrient TMDLs and Their Effect on Dredging Operations in the Chesapeake Bay

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  1. Nutrient TMDLs and Their Effect onDredging Operations in the Chesapeake Bay William J Rue- EA Engineering, Science, & Technology, Inc. Nathaniel Brown- Maryland Port Administration George Harman- Phoenix Engineering, Inc. Kenna Oseroff- Maryland Environmental Service Presenter Name 24 October 2012

  2. The Chesapeake Bay The Chesapeake Bay is the largest estuary in the United States • Watershed is 64,000 mi2, including parts of 6 states + DC • It is a significant regional environmental and economic asset

  3. Primary TMDL Issue: Extensive low summer dissolved oxygen conditions persist throughout the Chesapeake Bay and its Tidal Tributaries

  4. Nutrient Offsets and Trading • Any new or increased N or P load will be required to be completely offset • A new or expanding point source discharger must demonstrate that it has secured sufficient credits for 2 full NPDES permit terms (10-years); and must submit a plan showing how it intends to acquire the credits for at least 10-years beyond. • Options for offsetting new or increased loads/generation credits: • Upgrading an existing facility to BNR or ENR • Retiring an existing WWTP by connecting to an ENR facility • Innovative BMPs (e.g., water reuse, wetlands restoration/creation) • Market-based nutrient trading approach: 1 lb TN = $16-20/year ?? footer

  5. MPA’s Baltimore Harbor Operations MPA is responsible for managing dredging operations in Baltimore Harbor. The Chesapeake Bay TMDL is requiring significant changes throughout the watershed The consequences of CB-TMDL requirements have not been fully explored for atypical operations ( e.g., unpredictable loadings, seasonal only discharges, non-industrial & non-municipal effluent characteristics). footer

  6. MPA’s Baltimore Harbor DMCFs • MPA closed its 30-year old Hart Miller Island DMCF in 2009 (outside of the Harbor). • HMI was an 1,100 acre facility, restored for wildlife habitat • Replacement DMCF’s include: • Cox Creek DMCF – a renovated 100-acre • Masonville DMCF – new 130-acre site • Others (needed) ….. footer

  7. Hart Miller Island DMCF1,100 acre basin, 1981-2009, ~52 mcycapacity footer

  8. Baltimore Harbor DMCFs Cox Creek Site footer

  9. Cox Creek DMCF133 acres, 6 mcy capacity, 10-12 year life footer

  10. Masonville DMCF 178 acres, 16 mcy capacity, 20 year lifetime footer

  11. Key Regulatory Decisions • MDE requires State Discharge Permits for Harbor DMCFs • MDE transferred HMI load of TN and TP to Cox Creek and then reduced it by 50% • MDE assigned the other 50% to Masonville for 5 years then reduced it to a net zero as a “new” source for TN and TP • No credit given for permanent removal of nutrients, PCBs or metals from the Harbor • Currently MPA is conducting mass balance studies to show that dredging and placement into DMCFs sequesters TN, TP and PCBs. footer

  12. Key NPDES TMDL Permit Limits Each facility (Cox Creek and Masonville) allocated 50% of the HMI assigned loads (462,000 lbs/yr TN, 7,240 lbs/yr TP) Cox Creek will continue to have WLA of 231,000 lbs/year TN. Masonville DMCF loads to be a net zero by Nov 2015. footer

  13. NPDES Permit Negotiations Open Question: Should Masonville be a new source, requiring complete offset of discharged loads (+10 percent) Currently seeking an “umbrella” or “overlay” permit to manage ALL Harbor DMCF operations under the total 231,000 lbs/year TN and 3,620 lbs of TP allocations. Conducting permit required studies to quantify sequestration and exploring other BMPs (recirculation, treatment, floating wetlands, algal scrubbers, etc.) by DMCFs for nutrients and PCBs. footer

  14. Big Picture Issues • Ports have little ability to predict or manage seasonal/annual loading releases as required in typical permits. • Challenges: unanticipated new projects / timing / contracting / funding availability/project size • Pollutant loads in “new work” projects cannot be estimated • Require costly worst case load estimate predictions • Ports need operational flexibility when managing inputs to multiple DMCFs. • Policy is needed for load management after facilities are closed (current policy only addresses active facilities - HMI and PI) • A policy is needed managing credits generated for sequestered loads permanently removed from the Harbor and Bay? footer

  15. Big Picture Issues (continued) • Lack of a viable nutrient trading market to purchase or sell “approved” nutrient credits. • Will MPA be a buyer or a seller? • Quantifying the effectiveness of innovative DMCF management practices. • Recirculation of pond water for hydraulic offloading of barges. • Identifying funding needs (near- and longer-term) to comply with CB TMDL-based load allocations. footer

  16. Nutrient TMDLs and Their Effect onDredging Operations in the Chesapeake Bay THANKS Presenter Name 24 October 2012

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