CECW-PE 8 September 1999

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1. Review Comments:

A. Scarcity and Significance of the Resource. The main report, page 4-41 contains information on the significance of the hard bottom habitat and the associated giant kelp beds that would benefit from the proposed project. However, as cursory review of Figure 5 of the FWS Planning Aid Report indicates that kelp beds may not be particularly scarce in southern California. In order to establish a Federal interest in a restoration project, the district must document that the benefits will accrue to scarce and significant ecological resources. Please include a discussion of the scarcity of the resource in the project presentation.

District Response: Figure 5 of the Coordination Act Report shows the canopy of the giant kelp forest only of the Palos Verdes Peninsula in various years. Relative to the rest of the Southern California Bight, the Palos Verdes Peninsula does have a more rocky shoreline and more subtidal reefs than is typical of the Southern California coast and sub-tidal areas. The discussion that currently exists in Section 2.1 will be expanded to make it clear to the reader that natural hard rocky reef make up probably no more than about 5% of the marine substrate in southern California. As mentioned in Section 2.1, hard rock reef is considered so rare and valuable that the California Department of Fish and Game’s Marine Resources Divisions has a program to create and improve artificial reef habitat to augment the scarce natural rocky reefs. Section 2.1 will also be expanded to supplement the discussion on the value of kelp forests as an extremely productive biological community. The discussions that currently appear in Section 4.3.2.2 and 4.3.3.3 of the draft EIS/EIR, which address the rich diversity of marine invertebrates and marine fish that utilize the kelp forest, will be added to Section 2.1 to further support the "Need" for the project from a scarcity and significance of resource perspective. (Literally hundreds of marine invertebrates and over 120 marine fish species are known to occur in southern California kelp beds; this represents almost 23% of the known marine fishes of California).

Discussion: The information in the response was discussed and the district further clarified that the subtidal reefs and associated kelp beds are scarce when considering the extent of this habitat along California Coastline. The significance of the habitat was supported by representatives of the U.S. Fish and Wildlife Service, National Marine Fisheries Service, and the State Department of Fish and Game.

Action Required: Since the purpose of this project is ecosystem restoration and the scarcity and significance of the resource is key to the project justification, the information in the response must be clearly presented in the draft report and the executive summary, as well as in the draft EIS.

B. Impacts of Operation and Maintenance of the Project. The report should be revised to acknowledge that the recommended environmental restoration plan would most probably produce landslide stabilization effects. The recommended plan requires dredging to remove landslide material from the area behind the containment dike when filled. The filling of this area, in conjunction with the stone containment dike, would retard continued movement of the landslide and could result in significant landslide stabilization effects. Consequently, there could be economic impacts associated with maintenance activity that destabilizes the landslide or results in increased or more rapid movement of landslide material. The revised report should address the economic and environmental tradeoffs associated with the recommended OMRR&R. The economic impacts of landslide stabilization should be addressed.

District Response: The containment of continued landslide movement behind the dike is not expected to have any significant effect on reducing current landslide movement. This is because the driving force of the landslide will not be offset by the minimal buildup of material behind the dike. This is supported historically since the bluff overburden was at one time about 150 feet offshore of its present location. In regard to the impacts of OMRR&R, it is expected that removal of the bluff material, if plan 1 is selected, will not cause any greater impact than the without project condition since the contained material would have been otherwise eroded.

Discussion: The district reaffirmed that the offshore containment dike is not designed to reduce the current landslide movement and would not have any significant effect on its movement. The sponsor did express an interest in more frequent removal of bluff material as part of the project, in an effort to reduce the periodic operation and maintenance costs and environmental impacts. In this regard the district and sponsor may consider modifications to the plan that would include advanced removal of the bluff material. Maintenance requirements discussed in Comment 2.a. may result in the selection of the 400-foot location rather than the 200-foot location. Regardless of which project is proposed the sponsor will need to provide assurance that the project’s maintenance requirements will be met.

The U.S Fish and Wildlife Service representative, also, expressed concern with the potential stabilization of the slide as a result of the proposed project and noted inconsistencies in the information between the reconnaissance report and the AFB pre-conference documentation. Information in the reconnaissance report would lead one to believe that a containment dike is a requirement to stabilize the landslide. The draft feasibility report will explain any inconsistencies regarding the impact of offshore measures on stabilizing the landslide. If it is determined that the proposed project would significantly aid in the stabilization of the landslide, then the draft report and EIS must address the resulting impacts.

Action Required: The district will need to coordinate with the sponsor to determine if modifications to the plan that consider advanced removal of the bluff material should be proposed. Regardless of the project that is proposed, the sponsor will need to provide assurance that they will meet the project’s maintenance needs in a letter of intent that will be included with the final report. The district will reexamine the O&M requirements for each of the alternatives considered, and in the draft report will include a plan for OMRR&R for the selected plan. This OMRR&R plan will include any required actions to address the stability concerns of the district’s geotechnical staff. The impacts of implementing the OMRR&R plan will be included in the draft EIS. The plan will be accomplished in accordance with an O&M manual that will be prepared during PED. If it is determined that the proposed project would significantly aid in the stabilization of the landslide, then the draft report and EIS must address the resulting impacts.

C. Independent Technical Review. Significant geotechnical and engineering complexities are being evaluated in the study area. Complex coastal processes and the unstable slopes above the shoreline are significant considerations to the restoration proposals. Given the complexities of the study area and the acknowledged high levels of uncertainty for some of the study assumptions, we recommend that SPL and SPD continue with a rigorous QA/QC evaluation of the project engineering. Future report submissions must include documentation and certification of technical review as required by EC 1165-2-203.

District Response: The District is continuing working responses to review comments and certification will be submitted with the draft report. To date, most of the significant comments have been resolved subject to report revisions.

Discussion: CESPD guidance for the certification of independent technical review requires that the responsible functional chief (in this case the chief of Planning) certify the technical adequacy of the draft report. This individual is responsible for the overall quality of the product. Legal certification of the draft report is also required.

Action Required: The transmittal of the draft report will include the technical review documentation and technical certification by the responsible functional chief, as well as legal certification. The technical review documentation that is submitted with the draft report should indicate how technical review comments were addressed in the draft report.

D. Monitoring and Adaptive Management Plan. Appendix I of Volume 1 contains a placeholder for a monitoring and adaptive management plan. Although there could be cost shared monitoring proposed as part of the project, Corps policy regarding cost shared monitoring and adaptive management has of necessity become much more conservative. Revised guidance has been developed over the last 6 months to clearly state that most all monitoring for restoration projects will be the responsibility of the non-Federal sponsor.

District Response: A Plan is being prepared in accordance with current guidance and will be included in the draft report. The Plan will include monitoring of sites, analysis of problems if restoration does not occur as expected, and recommendations for remediation. The implementation of the monitoring plan and follow-up will be added to the first cost of the recommended plan.

Discussion: The monitoring plan should be developed to evaluate whether the restoration measures are working as designed. The monitoring/adaptive management plan should describe the nature of monitoring to be conducted as well as specify the finite period for which it will conducted. This basically comes down to a cost-sharing issue. The Corps participation in monitoring/adaptive management should not exceed five years and the cost-shared portion of the plan should not exceed 1-pecent of the total estimated project cost. Monitoring that is required for the OMRR&R of the project is a non-Federal responsibility.

Action Required: The draft report will include a monitoring/adaptive management plan. The cost-shared portion of monitoring/adaptive management will not exceed five years and should not exceed 1-pecent of the total estimated project cost.

E. Draft Fish and Wildlife Coordination Act Report. Based on the information in the draft CAR, and evaluations prepared by the National Marine Fisheries Service, there have been substantial disagreements among the Federal resources agencies regarding the potential benefits of the proposed project. Additionally, there is no indication in the report regarding the position of the state resource agencies. The district should be prepared to outline the process for addressing the concerns of the resource agencies especially considering the recent issues raised by the technical review.

District Response: The district will complete written responses to CAR comments in coordination with National Marine Fisheries and State Fish and Game. The district will, also, set up additional meetings to determine a plan of action to resolve any outstanding major issues. It may ultimately reach a point of agreeing to disagree. The status and final positions of the Fish and Wildlife Service and other agencies will be presented in the draft and final reports, respectively.

Discussion: The district reviewed the comments raised in the draft CAR and discussed preliminary responses. The district is continuing to coordinate the responses with the resources agencies and will attempt to resolve as many comments as possible.

The U.S. Fish and Wildlife Service representative expressed a number of concerns with the model that was used to evaluate and describe the project outputs, but agreed that the evaluation was acceptable for performing a relative ranking of alternatives. The Service’s representative also expressed concern that the restoration objective is not consistent with the evaluation and that the target is not clear. The draft report will need to clarify the restoration objective and the target levels.

The California Department of Fish and Game representative indicated support for the project provided that the district can demonstrate that it would provide beneficial effects. The EPA representative did not object to the project and believed it would provide beneficial effects.

Based on the discussions about the change in the OMRR&R requirements and the discussions related to the location of the dike (Comments 2.A. and 2.B.), it appears that the tentatively selected plan could change. The district will ensure that appropriate information is provided to the resource agencies pertaining to this change. The district will request a summary letter from the U.S. Fish and Wildlife Service for the draft report, revising their recommendations to reflect the district’s responses to the Service’s concerns and new information that is presented. The U.S. Fish and Wildlife Service will also update the CAR to reflect new information.

Action Required: The district will continue to coordinate with the resource agencies to resolve their concerns and provide them with any additional information pertaining to modifications to the tentatively selected plan. The draft report will clarify the restoration objective and target level of outputs. The district will request a summary letter from the U.S. Fish and Wildlife Service for the draft report, revising their recommendations to reflect the district’s responses to the Service’s concerns and new information that is presented.

(SPL identified several issues that could impact the recommended plan contained in the AFB material provided for review.)

A. Maintenance Requirements and Costs. The maintenance requirements and costs for removal of material behind the containment dike for plans 1 and 1 a (200-foot alternative) are underestimated based on considering the historic volume of sediment lost from the Portuguese Bend slide which is included in the sediment budget. The present report shows an estimate of the slide continuing at a average rate of 7.6 feet, but only the lower section of the slide was considered in the volume estimate, resulting in a volume to be removed of about 355,000 cy during the 20-year period before the slide reaches the dike structure. In response to the review comment, our analysis is being revised to reflect the average annual historic volume losses from the slide which is estimated to be 146,000 cy a year. This still reflects an average annual slide movement of about 7.6 feet per year but for the entire bluff face up to about 150 feet moving in a mass seaward (which has been experienced historically). The impact of this change requires increasing removal of about 3 million cubic yards at year 20 and year 40, at a cost of about $24 million each episode, or an average annual cost of about $630,000. This increases the total average annual cost for Plan 1 to about $ 2 million to restore a net 259 average annual habitat units, resulting in a cost of $7700/aahu. Consequently, Plan 2 becomes the NER Plan with a cost of $7500/aahu. This will be further discussed at the AFB.

Response: The revisions noted above reflect average annual historic slide material volume losses from Portuguese Bend slide that has been eroded from the bluff area. This is considered a more reasonable estimate of the volume of material that will be filling in behind the containment dike. The report will be revised accordingly.

Discussion: In responding to the district’s independent technical review comments, the costs for the removal of the material for the 200-foot location has increased by a factor of ten. The district presented a table reflecting the cost impact of additional removal of slide material on the alternatives considered. Based on these revised costs the 400-foot location would be the plan that would have the lowest cost per habitat unit. This evaluation did not, however, consider maintenance costs associated with wave action on the dike. The district will revise the evaluation of alternatives, giving full consideration to all OMRR&R costs and coordinate these revisions with the local sponsor. Based on this coordination, the district and local sponsor will either confirm or change the tentatively selected plan.

Action Required: The district will obtain a letter from the local sponsor indicating the locally preferred plan. When a tentatively selected plan is identified, the district will provide a summary of the changes and a revision to the NED table (Table 4-11 of the pre-conference documentation) to the CESPD and HQUSACE as a basis for a teleconference. The purpose of this teleconference will be to provide a quick review of the tentatively selected plan in order to give the district the authority to release the draft report.

B. Location of the Dike. There has been some concern that the 200-foot dike location may not be on stable foundation. There is essentially no data between the shoreline and 400-foot offshore. The District has carefully reviewed this concern and noted that an extrapolation of information available for the shoreline indicates the slide plane could surface within 200 feet of the shoreline. Accordingly, construction of the dike at 200-foot location is considered acceptable as long as subsequent slide movement over the slide plane does not impact on the structure. Maintenance to remove material prior to impacting on the structure has been included in the plans.

Response: Based on shoreline borings, the projection of the slide plane seaward indicates the likely emergence of the slide plane toe about 150 to 200 feet from the current shoreline.

As discussed in Comment 1B, geotechnical considerations indicate that a containment dike located 400 feet offshore would be outside the influence of the slide plane and would be the preferred location from an engineering standpoint. At this time the district does not have conclusive data concerning placement of containment dike closer to shore. However, the district and sponsor are comfortable with placement of the dike 200 feet offshore, since based on shoreline borings, the projection of the slide plane seaward indicates the likely emergence of the slide plane toe about 150 to 200 feet from the current shoreline. The difference in the two plans (400 foot versus 200 foot off shore containment dike), is essentially a tradeoff between higher upfront construction costs and higher O&M and potential replacement costs. The sponsor indicated that it would support the Corps regarding the proper placement of dike offshore. The district believes that with proper maintenance/replacement the dike will function as designed. The district also did not considered operation and maintenance associated with wave action on the dike. The district will review the required O&M and account for this requirement.

The NMFS representative expressed concern with the 200-foot offshore dike because of foundation uncertainties but indicated support for the 400-foot offshore dike if the district could ensure that it would work.

Action Required: The reevaluation of the OMRR&R costs that is discussed in Comment 2A, along with the risk associated with the dike location, will be included in a reconsideration of the plan selection. O&M costs to address wave action on the dike will be included.

C. New Slide. A new slide has occurred in the vicinity of Bunkers Point. This is a rotating slide that occurred on the 18th fairway of a $80 million new golf course and development currently under construction. The rotation of the slide impacted about 2000 feet of shoreline extending about 200 feet of water in depths of about 10 to 15 feet (rotation uplifted this section and left benthic life high and dry). The seaward face of the slide is cobble and rock to elevation of about 10 to 12 feet. It is expected that the developer will be stabilizing this slide area which would include eliminating erosion of the bluff and associated turbidity. They are currently developing plans for this purpose. This new slide impacts on a portion of the benefits claimed for reduced turbidity between Bunkers Point and Whites Point. The estimated area lost is between 1 and 20 feet and would reduce the benefits for each alternative by about 10 acres. This will be discussed further at the AFB.

District Response: The additional analysis of the impact of the new slide and local plans to stabilize the slide will be incorporated in the draft report.

Discussion: The developer is expected to control the slide area and remove the sediment that would be subject to erosion, thereby creating turbidity. The district will coordinate with the City to support these expectations.

Action Required: The draft report will be revised to reflect the local plans to stabilize the slide, including any available assurance that the plans will be implemented.

D. Unresolved technical Review Comments. SPL noted that additional unresolved comments are being addressed as part of the technical review.

Response: See response to comment on Independent technical review.

Discussion: The significant comments from the district’s independent technical review were discussed, along with proposed actions to be taken. Many of the AFB participants were impressed with the commitment of the district to the independent technical review process, which resulted in many frank discussions. All actions will be completed prior to the completion of the draft report. As indicated above, CESPD guidance for the certification of independent technical review requires that the responsible functional chief (in this case the chief of Planning) certify the technical adequacy of the draft report.

Action Required: The transmittal of the draft report will include documentation of the independent technical review and technical certification by the responsible functional chief, as well as legal certification.

E. Without Project Conditions. At the AFB a comment was raised concerning whether without project conditions reflect local efforts to stabilize the landslide.

District Response: Without project conditions reflect the slide will continue and local efforts are not effective in retarding the slide.

Discussion: This comment was addressed during the discussion of Comment 1.B.

Action Required: The draft report will clarify without project assumptions regarding local efforts to stabilize the landslide.

F. Conclusions: The district indicated they expect to revise the proposed recommendation to address remaining technical review and resource agencies concerns, and sponsor’s desire to perform advance bluff removal. In this regard prior to release of the draft report the division will initiate a telecon with HQUSACE and district staffs to discuss the proposed plan to be to recommended in the draft report and to expedite release of the draft report.