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Intent To Prepare a Draft Supplemental Environmental Impact Statement (DSEIS) for the Atchafalaya Basin Floodway System, Louisiana Project, Including Flat Lake Management Unit, Beau Bayou Management Unit and Cocodrie Swamp Management Unit, and Possible Modifications or Additions to the Buffalo Cove Management Unit, Located in St. Martin, St. Mary, Iberville, and Iberia Parishes, LA

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Department of the Army, U.S. Army Corps of Engineers, DOD.


Notice of intent.


The U.S. Army Corps of Engineers, New Orleans District (CEMVN), intends to evaluate water management features for the Atchafalaya Basin Floodway, System, Louisiana Project, excluding the Henderson Lake Management Unit, to improve water quality and interior water circulation, remove barriers to reestablish north to south water flow; provide input of oxygenated low temperature water; and reduce or manage sediment input into the interior swamp. The action is necessary due to the existing poor water quality resulting from the lack of internal circulation and oxygenated water inputs, and increased sedimentation. In addition if action is not taken, both deep-water and shallow water habitat utilized by fish and wildlife resources will continue to be lost, reduced, or degraded. The intended result of the proposed work is to prolong the life expectancy of the productive habitat (primarily aquatic and cypress tupelo habitats) that would become scarce over time by restricting or redirecting sediments, while simultaneously achieving a healthy water circulation pattern that would maintain or restore water quality and reestablish north to south water movement. This is a modification of the notice of intent posted in the Federal Register on July 16, 2004 (69 FR 42696).

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Questions concerning the DSEIS should be addressed to Mr. Larry Hartzog at U.S. Army Corps of Engineers, PM-RP, P.O. Box 60267, New Orleans, LA 70160-0267, phone (504) 862-2524, fax number (504) 862-2572 or by E-mail at

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The Corps of Engineers is initiating this DSEIS under the authority of the Flood Control Act of May 15, 1928 (Pub. L. 391, 70th Congress), as amended and supplemented. Construction of two pilot management units (Buffalo Cove and Henderson Lake) was authorized by the Supplemental Appropriations Act of 1985 (Pub. L. 99-88) and the Water Resources Development Act (WRDA) of 1986 (Pub. L. 99-662), with construction of three conditionally authorized management units—Flat Lake Management Unit, Beau Bayou Management Unit, and Cocodrie Swamp Management Unit to take place upon approval of the Chief of Engineers after evaluation of the operational success of the pilot management units. (Hereafter, the three conditionally authorized management units will be collectively referred to as “conditionally authorized management units”.) Section 601(a) of WRDA 1986 authorized the U.S. Army Corps of Engineers to carry out the recommended plan for management units as described in the Atchafalaya Basin Floodway System, Louisiana Feasibility Study and Environmental Impact Statement of January 1982, as approved by the Chief of Engineers Report dated February 28, 1983.

The Engineering Documentation Report (EDR), Buffalo Cove Pilot Management Unit (BCMU) and supporting Environmental Assessment (EA) No. 366 and Finding of No Significant Impact (FONSI) on July 15, 2004, satisfy the requirements of the National Environmental Policy Act (NEPA) for the referenced pilot water management unit impacts. The expected results of these improvements, while beneficially effective alone, will continue to contribute to the entire comprehensive BCMU improvements in water quality and habitat that will be expanded as additional possible elements are added in the future. Because the BCMU constitutes a “pilot” management unit, both the EDR and EA No. 366 clearly identify the possibility that additional future work may be recommended in the BCMU if the analysis of the operational monitoring data supports a finding that the present EDR elements do not fully accomplish the goals and objectives of the authorized management unit project.

The preparation of the DSEIS addressed by this NOI will commence and continue concurrently with the monitored construction and operation, data collection and analysis of the BCMU water circulation improvements and sediment management initiatives (as described in EA No. 366), as well as analysis and solicitation of public and resource agency input. Monitoring of the 10 elements and the elements constructed for the Bayou Eugene Prototype Model Test Modification (“Bayou Eugene”), comprising the water circulation and sediment management initiatives (described in EA No. 366) will continue for a period of 5 years following the construction of the last of the elements described in EA No. 366. If data collected during and prior to the end of the 5 year monitoring period indicates that modifications or relocations of elements within the bounds of the original project rights-of-way or areas of influence are needed to achieve the goals and objectives for fish and wildlife enhancement, a report will be prepared and submitted for approval. The DSEIS will be prepared following the incorporation and analysis of the data from the completed construction monitoring of the 10 elements as described in the approved EDR and EA No. 366. Construction monitoring described in the approved EDR is scheduled for completion 5 years after the construction of the last of the 10 elements is completed. Based on this completion date, construction monitoring and the concurrent DSEIS are currently estimated to be completed in 2012. The DSEIS will utilize the monitoring data to evaluate the Start Printed Page 44587operational effectiveness of the Bayou Eugene elements and the 10 elements described in EA No. 366 on the areas of influence outlined in EA No. 366. In addition, the DSEIS will evaluate the possible need for and effect of additional elements, and modifications or relocations of previously constructed elements to accomplish the fish and wildlife enhancement goals for the entire BCMU. The contemplated DSEIS will provide an overall evaluation of the influence of both previously constructed prototype model study features along Bayou Eugene, the currently proposed 10 elements (as described in EA No. 366), possible modifications, additions or relocations associated with the monitoring findings of EA No. 366, and the environmental impacts of the possible additional elements. Based on the analysis and evaluation of the operational effectiveness of the BCMU elements, including the Bayou Eugene elements, in enhancing the aquatic ecosystem and attaining the fish and wildlife enhancement goals of the management unit feature of the Atchafalaya Basin Floodway System, Louisiana project (ABFS), the DSEIS will investigate the feasibility of, and formulate recommendations for, the implementation and construction of the conditionally authorized management units. Henderson Lake Management Unit (Henderson Lake) is hydrologically separate and independent from all of the other authorized management units. Additionally, the management unit objectives, public interests and concerns that will be addressed at Henderson Lake differ substantially from those present for the other management units at Buffalo Cove, Flat Lake, Cocodrie Swamp and Beau Bayou. As such, Henderson Lake will be the subject of a separate DSEIS.

1. Proposed Action. The proposed action will consist of a series of closures and sediment traps (to reduce sediment influx); construction of new, or improvement of existing inputs for river water; and gap construction in existing embankments. Closures will be placed in areas that have the greatest potential for introduction of sediment. Closure heights will be designed to optimize sediment reduction. Construction of water inputs will be evaluated in areas where sediment-lean, fresh water sources can be easily connected to existing canals or bayous to conduit water into areas of poor water quality. Sediment traps will be designed as necessary in conjunction with the freshwater input sites. Gaps will be sized and placed in both elevated natural banks as well as dredged material embankments that impede water flow or induce stagnation. These gaps are primarily intended to improve drainage and reestablish flow through the interior swamp basin. Excavated material will be either placed in a non-continuous manner in order to not disrupt sheet flow, or if practicable, the material will be used to create closures.

2. Alternatives. The alternative formulation process will include an evaluation of the “no action alternative”, a monitored passive management plan, and the original structural alternative plan as proposed in the 1982 Atchafalaya Basin Floodway System, Louisiana Final Environmental Impact Statement which included construction of ring levees and active structures. The current alternatives analysis will continue to evolve throughout the development of the DSEIS. Alternatives to be evaluated include different methods of sediment reduction, water input, and improving internal circulation within the management unit. Sediment reduction alternatives will include the use of various sediment trap sizes and placements, construction of sediment traps with and without maintenance, and monitoring the effectiveness of sediment reduction utilizing both partial and complete closures at sites of suspected sediment inputs. Alternative methods will also be evaluated for water introduction and include; diverse configurations of water inputs (sinuous, straight, length and depth), improvements to existing natural and manmade inlets, reopening natural and man-made inputs, and siting of bank shavings to reduce barriers to water input. In addition, various sizes, numbers and placement of gaps in existing canal banks, ridges and other internal circulation impediments will be considered in the alternatives.

3. Scoping Process. The Council on Environmental Quality regulations implementing the National Environmental Policy Act (NEPA) process directs Federal agencies that have made a decision to prepare an environmental impact statement to engage in a public scoping process. The scoping process is designed to provide an early and open means of determining the scope of issues (problems, needs, and opportunities) to be identified and addressed in the draft environmental impact assessment, which in this case is a DSEIS.

Scoping is the process used to: (a) Identify the affected public and agency concerns; (b) facilitate an efficient DSEIS preparation process; (c) define the issues and alternatives that will be examined in detail in the DSEIS; (d) and save time in the overall process by helping to ensure that the draft statements adequately address relevant issues. Scoping is a part of the planning process, and will involve meetings, telephone conversations, and/or written comments. Scoping comments will be compiled, analyzed, and utilized in the plan formulation. A scoping report, summarizing the comments, will be made available to all scoping participants and included in the public involvement appendix of the report and DSEIS.

a. Public Involvement. Scoping is a critical component of the overall public involvement program. An intensive public involvement program will continue throughout the study to solicit input from affected Federal, state, and local agencies, Native American tribes, and other interested parties. This public input will be obtained through a series of scoping meetings open to the general public. In addition to these meetings there will be additional continual public involvement through the Louisiana Department of Natural Resources Division's Atchafalaya Basin Advisory Committee meetings on Water Management. CEMVN personnel will be available for additional informational meetings if needed or requested by various interested and/or affected public, private and conservation interests such as: landowners, oil and gas interests, commercial and recreational hunters and fishers, forestry interests, and the Sierra Club, Nature Conservancy, Audubon Society or other conservation organizations.

b. Significant Issues. The tentative list of resources and issues to be evaluated in the DSEIS includes forested wetlands (includes cypress/tupelo swamp as well as infrequently inundated areas of ash, oak, elm, hackberry and cypress), water quality, aquatic resources, commercial and recreational fisheries, wildlife resources, essential fish habitat, water quality, air quality, threatened and endangered species, recreation resources, and cultural resources. Socioeconomic items to be evaluated in the DSEIS include employment, land use, property values, community and regional growth, transportation, housing, and community cohesion.

c. Interagency Coordination. The Department of Interior, U.S. Fish and Wildlife Service (USFWS), will provide a Fish and Wildlife Coordination Act Report. Coordination will be maintained with the Natural Resources Conservation Service regarding prime and unique farmlands. Coordination will be maintained with the Advisory Counsel on Historic Preservation and the State Historic Preservation Officer. Start Printed Page 44588The Louisiana Department of Natural Resources will be consulted regarding consistency with the Coastal Zone Management Act. The Louisiana Department of Wildlife and Fisheries will be contacted concerning potential impacts to Natural and Scenic Rivers and Streams. The Louisiana Department of Environmental Quality will review the action for consistency with applicable laws regarding the discharge of dredged material as it relates to impacting water quality and will provide the State of Louisiana Water Quality Certification.

d. Environmental Consultation and Review. The U.S. Fish and Wildlife Service (USFWS) will be assisting in the documentation of existing conditions and assessment of effects of project alternatives through Fish and Wildlife Coordination Act consultation procedures. Consultation will be accomplished with the USFWS and the National Marine Fisheries Service (NMFS) concerning threatened and endangered species and their critical habitat. The NMFS will be consulted on the effects of this proposed action on Essential Fish Habitat. The DSEIS or a notice of its availability will be distributed to all interested agencies, organizations, and individuals.

4. Public scoping meetings are to be scheduled throughout the DSEIS preparation period. Based on available funding the tentative meeting locations will be Baton Rouge, Lafayette and St. Martinsville, LA. Exact dates and meeting facility will be announced by public notice at a later date. The purpose of the scoping meeting is to provide the agencies and the interested public with the initial conceptual designs, known preliminary designs and other designs under consideration for the proposed management unit project for the Buffalo Cove Management Unit and issues concerning its construction and operation. If determined to be feasible and appropriate for implementation (based upon the determinations of the operational effectiveness of the BCMU) scoping meetings will also provide the agencies and the interested public with the initial conceptual designs, preliminary designs known and designs under consideration for the proposed for the conditionally authorized management units and issues concerning their construction and operation. These scoping meetings will be sequenced such that the data stream from the ongoing monitoring (associated with the 10 elements in the BCMU) can be utilized to assist in the formulation and design of elements planned for the three conditionally authorized management units. The scoping process, more importantly, will provide the opportunity to solicit public views on the proposed action and provide input to development of project alternatives. The initial scoping meetings will focus on the Buffalo Cove Management Unit (including the operational success of the ten elements described in EA No. 366, modification of those ten elements and construction of new elements for the Buffalo Cove Management Unit) and preliminary discussions of problems and possible alternatives for the three conditionally authorized management units. As additional information is available on the operational effectiveness of the monitored EA No. 366 elements and as the existing conditions and potential management alternatives for the conditionally authorized management units are better defined, the agenda of the scoping meetings will be expanded to address the feasibility of implementing the conditionally authorized management units.

5. Estimated Date of Availability. Funding levels will dictate the date when the DSEIS is available. The earliest that the DSEIS is expected to be available is in the fall of 2012.

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Dated: July 18, 2005.

Richard P. Wagenaar,

Colonel, U.S. Army, District Engineer.

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[FR Doc. 05-15298 Filed 8-2-05; 8:45 am]