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HomeMy WebLinkAboutSS2 - Update on Lower Bay Dredging Issues - PPT1LowerNew port Baj Dredging U pdate City Council Study Session April 14, 2009 Harbor Resources Discussion Topics Brief overview of Upper Newport Bay dredging project Why dredging the Upper Bay helps the Lower Bay. Status of current testing program in the Lower Newport Bay Discuss contaminated disposal options Tonight's Council request Next steps Two Components of Dredgin g LNB Funding Federal funds are not immediately available, but: Stimulus funding Other national projects are more "shovel ready" — waiting game. Regular Federal budget, FY 2010 and beyond. Corps is committed to helping Newport achieve our dredging goals, and will prioritize Newport's project assuming funding occurs and especially if the City solves the contaminant issues. City's contribution will jumpstart the project and will address the difficult issues. Development of a Sampling and Analysis Plan (SAP) How to dispose contaminated sediments Two Components of Dredging LNB (cont'd) z. Testing Development of a SAP Development of a CAD (Confined Aquatic Disposal) for contaminants. Corps will not assist without a disposal plan in place. Iq Both of these components (funding and testing) are very complex tasks which require: Coordination Planning Outreach Time What is within the City's control? ... Testing! New Fields Northwest, LLC Hired by the City in September 2008 to evaluate the sediment for the entire Lower Bay and to develop a Dredged Material Management Plan (DMMP). Goal: maximize disposal of clean material at LA -3. Bathymetry study complete Comparison of depths between 2005 and 2008 surveys. What is within the City's control? ... Testing! New Fields Northwest, LLC v Amphipod species selection. These are benchmark critters that are used for survivability and toxicity tests. Challenges: Complex evaluation to chose a species. If species survival is in question, it's important to understand why, and, if possible, change the species — this took more time than we anticipated. Study now complete. What is within the City's control? ... Testing! New Fields Northwest, LLC SAP has been submitted to a newly formed Dredged Material Management Team (all agencies represented) in late April. They will discuss: Roles for each of the agencies Mercury deposition LA -3 Reference database Details of SAP Relevance of past data and applicability to current program This is a com licated rocess reguiring concurrence with many agencies. What to do with the contaminants? Anchor QEA Hired by the City in December 2008 to develop a Concept Plan for contaminant disposal. D Various options considered: On -Site sediment treatment facility Li Future port fill Li Upland landfill disposal Long Beach confined aquatic disposal (CAD) site Lower Newport Bay CAD site On -Site Treatment Cement -based Stabilization • Cost effective • Treats metals and organics • Agency approved process • Removes material from water On -Site Treatment: • Sand Separation Process is cost effective Can remove metals and organics Removes material from the water Creates beneficial product • Lack of recipients for treated material • Unclear agency support • Upland treatment site • Multiple re- handling • Adjacent land impacts significant • Slow (1,000 cy per day) • Process not refined • Unclear agency support for material re -use • Still requires disposal of fine grained material • Requires adjacent land for treatment facility Future Port Fill • Cost effective Limited duration of • Agency approved availability; highly schedule management approach dependent • Removes material from Uncertain schedule for the water permits and authorizations • May not be able to accept all material requiring disposal • Liability transfer agreement with port will be required • Does not provide a guaranteed solution for the City Lower Newport �r • Cost effective compared Local community will be p Bay CAD Site to upland disposal impacted in terms of • Can accept all material aesthetics and disruption to at once navigation • City controls schedule Temporary displacement of and process some boaters • Use Port Hueneme as Environmental groups might example for permitting be opposed to disposing of and design contaminated sediments in • Cell excavation could the bay provide material for beach nourishment Tonight's Council Request Geotechnical exploratory work is required prior to committing to the CAD option Anchor QEA Proposal: Collect and analyze sediment cores to -60' MLLW in order to: Ensure beach suitable material exists (physically and chemically) Collect data to assist in developing a preliminary CAD design (i.e. size, shape and side slopes) Work completed by May 2009 rigum i tzANCHOR Example CAD Cell Looatlons and Pmposed Sampling Locations QEA Lower Newport Bay CAD Site Feasibility Study a� 1 Nb,USKE,e�rxrf tlpgarakfhgro _� I I WYYrmwIf zow . - ref L.wu.m.n,iLa e.n.e.w4ave —�— a,arN�. uwav Nrao.i neu a.0 WNY.Ne.d� a4mMYree.e0 fwwflM�s.,a Iw�4.Ny.nwY bo�rtM aarnra,N.� 4 I.mf,wiwmm VvOYa, �eseq QUA a— .ia rtY CID (m4e0 Kuu[ d.aeN QM- 41�b�1. L M�wwenel'Y+!M1 M YfK{- LL5.4mYfvP✓ f'Vmn p1Yal Mwyo Bma� �tl US.Q nsrrai nw,W M.M.fLD A.If.nt PW�aN4�, If.r. W.Ma,p .N aF..WaYY For More Information http:// www .city.newport- beach.ca.us /HBR/ Chris Miller, Harbor Resources Manager cmiller (a�� citewport- beach.ca.us (949) 644 -3043 Shannon Levin, Harbor Resources Supervisor shan non (ccity.newport- beach. ca. us (949) 644 -3041