West Neebish Island Rock Cut Town of Barbeau, Chippewa County, Michigan Section 106 of the National Historic Preservation Act Ma

West Neebish Island Rock Cut Town of Barbeau, Chippewa County, Michigan

Section 106 of the National Historic Preservation Act

March 2015

U.S. Army Engineer District, Detroit Corps of Engineers, CELRE-PL-E 447 Michigan Avenue Detroit, Michigan 48226-2550

US Army Corps of Engineers® Detroit District

West Neebish Island Rock Cut Town of Barbeau, Chippewa County, Michigan

Section 106 of the National Historic Preservation Act

TABLE OF CONTENTS

1. Introduction ...... 1 2. Project Authority ...... 1 3. Project Purpose and Need ...... 1 4. Project Alternatives ...... 2 4.1 Alternative 1: A sloped rip rap wall from +7 LWD to -4 LWD (or bedrock)...... 2 4.2 Alternative 2: Grouting of the existing ashlar wall ...... 2 4.3 Alternative 3: Replacement of the missing stone with 10 to 18 ton quarry stone ...... 2 4.4 Alternative 4: Rock fall netting ...... 3 4.5 Alternative 5: No Action...... 3 5. Agency Coordination ...... 4 6. Conclusions ...... 5 7. Public Review ...... 5

List of Figures and Enclosures

Figure 1-West Neebish Island Channel Rock Cut Location Figure 2-Alternative 1 Cross Section Enclosure 1 – SHPO to USACE - Disagree with USACE finding of No Adverse Effect Enclosure 2 – USACE to SHPO - Proposal to test Alternative 2 Enclosure 3 – SHPO to USACE - Agree to Alternative 2 test Enclosure 4 – USACE to SHPO - Notification of “adverse effect” finding and request for further consultation Enclosure 5 - USACE to ACHP - Notification of “adverse effect” finding and request for further consultation

1. Introduction

The U.S. Army Corps of Engineers, Detroit District (USACE), is proposing to make alterations to the West Neebish Island Channel Rock Cut (Rock Cut), located within the St. Marys River, Chippewa County, Michigan (Figure 1). The Rock Cut has been determined eligible for the National Register of Historic Places. The purpose of this document is to describe the proposed project and the USACE findings pursuant to Section 106 of the National Historic Preservation Act.

2. Project Authority

Work at the Rock Cut is authorized by various acts of Congress governing the construction, operation and maintenance of USACE property.

3. Project Purpose and Need

The West Neebish Island Channel Rock Cut (Rock Cut) is located on the west side of Neebish Island in northern Michigan. The Rock Cut was built in order to allow two way shipping traffic around Neebish Island. The Rock Cut walls have failed and been reconstructed multiple times since the Rock Cut’s original construction in 1902 (Enclosure 5, Attachment 6, Photo 1 and 2). The Rock Cut channel was deepened in 1932, during which large portions of the rock walls were rebuilt (Enclosure 5, Attachment 6, Photo 3 and 4). The channel was deepened again in 1960 and again large portions of the rock walls were rebuilt (Enclosure 5, Attachment 6, Photo 5 and 6). In 1977 further repairs were attempted using precast concrete blocks but by 1996 the repair had failed (Enclosure 5, Attachment 6, Photo 7). The USACE further attempted to use steel frames and anchor weights to repair the walls by concreting the blocks in place (Enclosure 5, Attachment 6, Photo 8). These attempts were unsuccessful.

The rock walls were not designed to current engineering standards and even after being rebuilt twice and repaired numerous times they still are not strong enough for continued use. The original design allows water to exist between the blocks at and below the waterline. The freeze/thaw of the water between the blocks is one of the causes for failure of the rock walls. Additionally, further strain is placed on the wall by friction caused when ice forms within the Rock Cut. This strain is exacerbated and causes further deterioration when the ice is broken by ice cutters and then pushed against the wall by vessels transiting the Rock Cut.

Due to the history of multiple wall failures and the failure of grouting and various other repair attempts, the USACE has determined that it is no longer feasible to continue maintaining the Rock Cut walls via reconstruction. Their continued failure is due to inadequacy in the original design and they will continue to fail regardless of how many times the walls are rebuilt. In order to maintain the Rock Cut into the future and remove the threat to navigation, the USACE is proposing to remove the existing Rock Cut walls sections that remain down to four feet below (-4) Low Water Datum (LWD)

and replace them with a suitable alternative (Enclosure 5, .

4. Project Alternatives

Given the need for safe navigation through the Rock Cut, the USACE has evaluated the following alternatives: 1) a sloped riprap wall from +7 LWD to the existing bedrock, 2) grouting of the existing ashlar wall, 3) replacement of the missing stone with 10 to 18 ton quarry stone, 4) Rock fall netting, and 5) No Action.

4.1 Alternative 1: A sloped rip rap wall from +7 LWD to -4 LWD (or bedrock)

Alternative 1 involves excavation of the existing ashlar masonry walls to either sound bedrock or to approximately -4 LWD, a depth below the typical ice formation line. A new sloped wall would be reestablished starting at approximately 7 feet behind the vertical face of the ledge and would include an armoring 2.5 foot thick layer of 200 to 400 pound rip rap stone (Figure 2). The advantage of this alternative is that the resulting structure would have a much more stable angle of repose which will reduce the likelihood of complete washouts. In addition, incorporating the horizontal ledge provides for an area where any lost material would accumulate thereby reducing the risk of rock materials ending up in the navigation channel. This alternative has been found to be the most cost effective as all materials required could be obtained by reusing of existing wall materials and from the adjacent rock spoil piles.

4.2 Alternative 2: Grouting of the existing ashlar wall

Alternative 2 involves pumping grout into the voids and joints of the wall to develop a solid gravity structure that will resist shear failure due to lateral earth and surcharge pressures. In addition, the presence of grout in the joints between the blocks could reduce the potential for the negative effects of freeze/thaw action. Rebuilding of already failed sections of the wall with either stone or concrete blocks would also have to be undertaken prior to the grouting process.

A previous past pilot project testing of the grout in place alternative proved unsuccessful due to the velocity of water through the Rock Cut. In addition, proper implementation of the alternative would include not completely filling all voids below the ice line to allow for free drainage from behind the wall, which still leaves the structure susceptible to freeze/thaw impacts depending upon water levels.

4.3 Alternative 3: Replacement of the missing stone with 10 to 18 ton quarry stone

Alternative 3 involves the placement of quarry stone in place of the existing ashlar walls. The construction operation would consist of first excavating the ashlar masonry wall to an elevation on -4.0 LWD or to bedrock. Six foot wide stone blocks of various lengths and thicknesses would then be used to reconstruct the guide wall. In areas

where the bedrock extends below elevation -4.0 LWD the existing masonry units would be used to support the quarry stones. A variation of this alternative would entail use of concrete blocks in lieu of quarried stone, the advantage being the ability to utilize some on-site materials and have more flexibility in varying the size of the blocks to better match onsite conditions.

Both of these alternatives that entail rebuilding the guide walls will be very costly as new materials are required. A more important consideration is that the alternative does not adequately address the underlying cause of continuing wall failures – loss of stability of vertical stacks of stone blocks without mortar between blocks as weathering and ice action continues to deteriorate the materials at the waterline.

4.4 Alternative 4: Rock fall netting

Alternative 4 involves the placement of a 12-inch diagonal mesh, 5/16 inch diameter stainless steel cable net over the top and face of the existing masonry walls. The net hold the masonry units in place and prevents further washouts. The top of the net would be connected by wire rope to anchors set back behind the wall. The bottom of the net would be connected to the bedrock ledge beneath the wall by use of smaller diameter rock anchors. Existing areas of washed out wall would have to first be rebuilt with cut stone blocks and/or precast concrete blocks.

There are several concerns associated with this repair alternative. From a constructability standpoint, the setting of the rock anchors below the existing wall to bedrock interface will require the use of divers and/or some type of moveable cofferdam. This adds considerable additional cost to the repair and creates additional construction safety concerns due to the high current within the Rock Cut. An additional concern would be the durability of the resulting repair. There is a concern that ice forming in and around the rock fall netting could result in increased outward forces pulling against the wall during spring thaw and when vessels are navigating through the Rock Cut under ice conditions.

4.5 Alternative 5: No Action

Alternative 5, the No Action alternative, involves leaving the remaining Rock Cut walls in place. While this alternative would maintain some of the historic integrity of the Rock Cut, the design deficiencies of the Rock Cut walls present a safety risk to shipping and continued operation/maintenance of the Rock Cut.

5. Agency Coordination

Per Section 106 of the NHPA, the proposed project information was coordinated via written correspondence in 1999 to the Michigan State Historic Preservation Office (MI SHPO). The MI SHPO responded on August 10, 1999 and did not concur with the initial USACE determination of “no adverse effect” under 36CFR800.5 (Enclosure 1). The MI SHPO determined that all the proposed alternatives would have an “adverse effect” on the West Neebish Channel Rock Cut.

Of the proposed alternatives, the MI SHPO determined that Alternative 2: Grouting of the existing ashlar wall would be the least harmful to the historic integrity of the Rock Cut. The second best alternative, in the opinion of the MI SHPO, was the use of quarry stone as it would appear somewhat similar to the existing masonry. Additionally, the MI SHPO determined that Alternative 1: A sloped rip rap wall from +7 Low Water Datum (LWD) to - 4 LWD (or bedrock) would greatly alter the appearance and historic design for the Rock Cut.

The USACE proposed a test of Alternative 2 be conducted on a portion of the Rock Cut walls to determine its effectiveness. The USACE determined that this test would have “no adverse effect” on the Rock Cut walls. The MI SHPO concurred with this finding on November 29, 1999 (Enclosure 2).

The USACE conducted the grouting test repair on 100 feet of both the mainland and island walls in 2000. The grouting repair was determined to be unsuccessful; however, as the grout was either washed away by the strong currents through the Rock Cut or was absorbed by the surrounding soil.

Because of the failure of the grouting test and the extensive costs and other concerns associated with implementing Alternatives 2-5, including concerns over public safety and the increasing hazard to navigation, the USACE decided to proceed with Alternative 1: a sloped rip rap wall from +7 Low Water Datum (LWD) to -4 LWD (or bedrock).

The USACE began implementation of Alternative 1 on the mainland side of the Rock Cut in 2014. Work on the mainland side was almost complete when the USACE realized that the Section 106 process had not been completed regarding the effects of implementing Alternative 1.

Upon cessation of work, the USACE began a review of the Rock Cut project and determined that implementing their selected alternative (Alternative 1) was having an “adverse effect” on the historic integrity of the Rock Cut and that further Section 106 coordination with both the MI SHPO and the ACHP was necessary.

The USACE reinitiated the Section 106 process in November 2014 by sending similar letters to both the MI SHPO and the ACHP (Enclosures 4 and 5). The letters notified both parties that the USACE had begun implementing the selected alternative

(Alternative 1) on the mainland side of the Rock Cut and the USACE had ceased construction when it was realized that the Section 106 process had not been completed. Further, the USACE stated that it had determined that the selected alternative was having and would continue to have an “adverse effect” on the historic integrity of the Rock Cut and requested that the MI SHPO and ACHP enter into consultation so appropriate mitigation could be developed.

After phone calls between the USACE, MI SHPO and the ACHP on January 8, 2015 and on February 4, 2015 the USACE and MI SHPO have agreed to develop a Memorandum of Agreement (MOA) regarding mitigation of the “adverse effect” on the Rock Cut, with the ACHP providing oversight and recommendations during the development of the MOA.

6. Conclusions

The USACE has determined that the implementation of the Alternative 1 on the mainland side of the Rock Cut and the proposed implementation of the same action on the island side of the Rock Cut, under 36CFR800.4, has had and will have an “adverse effect” on the West Neebish Channel Rock Cut.

The USACE also determined that it was the gap in funding from project initiation in 1999 to actual project construction in 2014 that led to the Section 106 coordination not being completed before implementation of Alternative 1 began. In order to ensure that this does not occur again, the USACE Operations Program Management Plan will be updated to deal specifically with Section 106 of the NHPA and ensure that the Section 106 process is completed before projects are initiated.

While the USACE acknowledges the oversight of not finishing the Section 106 process before the start of the project, the USACE maintains that due to the fundamental flaws of the Rock Cut walls that it was necessary to implement Alternative 1 to ensure safe navigation through the Rock Cut.

The USACE will continue to work with the MI SHPO and ACHP to mitigate the “adverse effect” that implementing Alternative 1 will have on the West Neebish Rock Cut through the development of an MOA. While the MOA and the mitigation is still being developed, all parties have agreed that public participation in the Section 106 process is critical and that the public should be notified of the project and the development of the MOA.

7. Public Review

This document addresses the proposed Federal action of continuing to implement Alternative 1 (the sloped rock wall) at the Rock Cut. This document will be made available for a 30-day public review period to the Michigan State Historic Preservation Office, Advisory Council on Historic Preservation, Native American interests, other Federal, state, and local agencies, interested groups and the public. Comments

received will be considered by the USACE. The USACE, through consultation with the MI SHPO and ACHP, will make a final determination on what mitigation will be appropriate in preserving the history integrity of the Rock Cut.

• St Jo~eph /sli'lnd Sources: Esri, HERE, Del orme, TomTom, lntermap, in crement P Corp., GEBCO, USGS, F:AO, NP~. NRCAN, GeoBa'se, IGf)J, Kadaster t-.~ L , Ordnance Suryey, Esri Japan,

on or guaranty, r express or as to cont en t, sequence, a ccura cy, time liness or completeness of any of the data here in_ USACE, its officers, a gents, or employees shall assume no liability of any nature for a ny of the data prov ided regardless of how caused_ USACE, its offi cers , a gents , or employee s sha ll assume no lia bility for any decisions made or a ctions ta ken or not taken by the use r of the maps and associated data in reliance upon any informa tion or da ta furnished here _ By using these ma ps and associa ted d ata the use r does so entirely a t their own ri sk a nd e >;~ lic itly a cknowle dges that Notes: 1984 WGS World Pro]ectron he /she is aware of a nd agrees to be bound by this discla imer and a grees no to present any cla im or demand of a ny nature aga inst USAC E, its Project dimensions are approximate officers , a gents or e mployees in any foru m whatsoever for a ny da mages of any nature wha tsover that may result from or ma y be ca used in any way by the use of the ma ps a nd associated data Image produced under license from ESRI Date: 3/6/2015 Figure 2

Figure 2-Alternative 1 Cross Section MICHIGAN DEPARTMENT OF STATE Candice S. Miller, Secretary of State-- Lansing1 Michigan 48918-0001

STATE HISTORIC PRESERVATION OFFICE Michigan Historical Center 717 West Aliegan Street Lansing, Michigan 48918-1800

August 10, 1999

DAVIDL DULONG_ DEPARTMENT OF THE ARMY DETROIT DISTRICT CORPS OF ENGINEERS BOX 1027 DETROIT MI 48231-1027

RE: ER-930113 Rehabilitation ofNeebish Island Rock Cut Guide Walls, Course 6, West Neebish Channel, St. Marys River, Chippewa County (COE)

Dear Mr. Dulong:

Under th,~ authority of Section 106 of the National Historic Preservation Act of 1966, as amended, we have _reviewed the above-cited undertaking at the location noted above. Based on the inforn1ation provided for our review, it is the opinion of the State Historic Preservation Officer (SHPO) that all of the proposed alternatives will have an adverse effect on the West Neebish Channel Rock Cut, which appears to meet the criteria for listing _in the National Register ofHistoric Places. -

Of the proposed alterruitives, grouting the existing ashlar wall will cause the least harm to the structure's historic character and design. This aJtemative will still have an adverse affect, however, because the limestone ashlar walls are not currently mortared. The adverse effect of this alternative ccmld be reduc_ed by recessing the outer surface of the grouting from the wall face, to a distance that _will render it as little visible as possible.

The second best alternative, in our optnion, is the use of quarry stone. If we understand the project correctly, this method would continue a manner of repair that the Corps hasused for the RocK: Cut in the past-and it will appear somewhat similar_ to the existing stone masonry. -

In our opinion, the shaped rip rap alternatives will greatly alter the appeanince and historic design of the West Neebish Channel Rock Cut.

The undertaking meets the following criteria of adverse effect outlined in federal regulation 36 CPR§ 800.5(a)(l): the _undertaking may alter, directly or indirectly, any of the characteristics of d historicproperty that qualify the property for inclusion in the National Register in a manner that would diminish the integrity of the property's location, design, setting, materials, workmanship,-jeeling, or association. Specifically, the undertaking will result in

• Alteration of a. property, including restoration, rehabilitation, repair, maintenance, stabilization, hazardous matedal remediation and provision of handicapped access that is not consistent with the Secretary's Standards for the Treatment of Historic Properties [36 CPR§ 68] and applicable guidelines The finding of adverse effect will prompt the Corps of Engineers, hereinafter referred to as "Agency", to consult further to resolve the adverse effect pursuant to 36 CFR § 800.6 by proceeding with the following steps:

(1) Per 36 CFR § 800.6(a), the Ageti."cy shall contiime consultati~n with the SHPO and other consulting parties to - develop and evaluate alternatives or modifications to the undertaking-that could avoid, minimize or ·mitigate adverse effects on -historic properties. The Agency shall submit a case study outlining these efforts for review by the SHPO.

(2) In accordance with 36 CFR § 800.6(a)(4), the Agency shall make information regarding this finding available to the public, providing the public ·with an opportunity to express their views on resolving adverse effects of the undertaking. Pursuant to 36 CFR § 800.11(e), copies or summaries ofany views provided by consulting parties -and tlie public shall be made available to the SHPO as part ofthe case study outlined in (1 ).

(3) The Agency shall immediately notify the Advisory Council on Historic Preservation (Advisory Council), Old Post Office Building, 1100 Pennsylvania Avenue, NW, Suite 809, Washington, D.C. 20004, ofthe adverse effect finding [36 CFR § 800.6(a)(1)]. The notification to the Advisory Council should be similar to the project information submitted to this office and should include the following documentation [36 CFR § 800.11(e)]: • A description ofthe undertaking, specifying the federal involvement, and its area of potential effects, including photographs, maps and drawings, as necessary • A de§cription of the steps taken to identify historic properties • A descriptionofthe affected historic properties, including-information on the characteristics that qualify them for the National Register · • A description of the undertaking's effects on historic properties • An explanation of why the criteria of adverse_ effect were_ found applicable or inapplicable, including any conditions or future actions to avoid, minimize or mitigate adverse effects • Copies or summaries of any views provided by consulting parties and the public

(4) If the -undertaking will affect a National Historic Landmark, if a programmatic agreement will be developed as a . result of the finding ofadverse eff_ect, or if it so desires, the Agency may use the opportunity to notifythe. Advisory Couneil of the adverse effect finding to invite the Advisory Council to participate in consultation. The Advisory Council will advise of its decision to participate in consultation within fifteen (15) days ofreceipt of this notification or other request. If the Advisory Council chooses notto participate in consultation, the Agency

shall resolve- the adverse effect without Advisory Council participation. and pursuant to 36 CFR § 800.6(b)(1

(5) If the Agency, the SHPO and (if applicable) the Advisory Council agree on how the adverse effects will be resolved, they shall execute a Memorandum of Agreement (MOA) pursuant to 36 CFR § 800.6(c).

(6) ·If the Agency and the SHPO fail to agree on the terms of a MOA, the Agency shall request the Advisory Council to join the consultation. If the Advisory Council decides to join the consultation, the Agency shall proceed in accordance with 36 CFR § 800.?(b)(2). If the Advisory Council decides not to join the consultation, the Advisory Council will notify the Agency and proceed to comment in accordance with 36 CFR § 800.7, "Failure to resolve adverse effects".

While consultation with the SHPO must continue for the selection of a preferred alternative, we concur with the Corp's proposal to mitigate the adverse effect through, at a minimum, recordation of the existing Rock Cut. The State Historic Preservation Office is not the office of record for this undertaking. -You are therefore asked to maintain -a copy of this letter with your environmental review record for this undertaking. If the scope of work changes in any way, or if artifacts or bones are discovered, please notify this office immediately .

. Please note that the Section 106 process will not -be -completed until the consultatio~ process is complete, a _Memorandum of Agreement is developed, executed and implemented, and, if applicable, the- fohnal comments of the Advisory Council have been received.

If you have ani questions, please contact Martha MacFarlane, Environmental-Review Coordinator, at (517) 3 3 5- 2721. Thank you for this opportunity.to review and comment and for your cooperation.

Brian D. onway State Historic Preservation fficer

BDC:JRH:ROC:krj

cc: . Advis()ry Council on Historic- Preservation OCT 2 6 1999

Engineering & Planning Division Environmental Analysis Branch

Mr. Brian Conway · sta:t·e Historic Preservation Officer Michigan Department of State 717 W. Allegan Lansing, Michigan 48918

Dear Mr. Conway:

This is in response to your August 10, 1999 letter regarding the rehabilitation of the Neebish Island Rock Cut Guide Walls, Course 6, West Neebish Channel, St. Marys River, Chippewa County (ER-930113). During an October 7, 1999 telephone conversation, Ms. Martha MacFarlane, of your office, and Dr. Karen Krepps, District Archeologist, discussed the various aspects of the proposed project. This letter provides a summary of their discussion.

The Corps has evaluated the rehabilitation alternatives and has selected as a test case, the alternative recommended in your August letter. This alternative is to grout the existing ashlar wall and recess the outer surface of the grouting from the wall face, to a distance that will render it as little visible as possible. This test case will involve 100 feet on the east wall and 200 feet on the west wall. The added length on the west wall is due to the inclusion of an extensive washout as part of the test case.

We have determined that the "test" of the rehabilitation alternative will result in a no adverse effect on the historic character of the structure under 36CFR800.5(b). This method will follow the Secretary of the Interior's Standards and Guidelines and the result of the test will be coordinated with your office prior to any additional rehabilitation of the structure.

With this letter we are requesting your concurrence in our determination. Should you have any immediate questions please contact Dr. Krepps, at 313/226-6238, or Mr. Les Weigum, Chief, Environmental Analysis Branch.

Sincerely,

~;7/ft-- David L. Dulong, P.E. hief, Engineering & Planning Division MICHIGAN DEPARTMENT OF STATE Candice S. Miller, Secretary of State Lansing, Michigan 48918-0001

STATE HISTORIC PRESERVATION OFFICE Michigan Historical Center 717 West Allegan Street Lansing, Michigan 48918-1800

November 29, 1999

DAVID L DULONG DEPARTMENT OF THE ARMY DETROIT DISTRICT CORPS OF ENGINEERS BOX 1027 DETROIT MI 48231-1027

RE: ER-930113 Test of Rehabilitation Alternative for Neebish Island Rock Cut Guide Walls, Course 6, West Neebish Channel, St. Marys River, Chippewa County (COE)

Dear Mr. Dulong:

Under the authority of Section 106 of the National Historic Preservation Act of 1966, as amended, we have reviewed the above-cited undertaking at the location noted above. Based on the information provided for our review, the State Historic Preservation Officer (SHPO) concurs with the determination of the Corps of Engineers that the effects of the proposed undertaking does not meet the criteria of adverse effect outlined in the federal regulation 36 CFR § 800.5(a)(1). Therefore, the project will have no adverse effect [36 CFR § 800.5(b)] on the West Neebish Channel Rock Cut, which appears to meet the criteria for listing in the National Register of Historic Places.

The State Historic Preservation Office is not the office of record for this undertaking. You are therefore asked to maintain a copy of this letter with your environmental review record for this undertaking. If the scope of work changes in any way, or if artifacts or bones are discovered, please notify this office immediately.

If you have any questions, please contact Martha MacFarlane, Environmental Review Coordinator, at (517) 335- 2721. Thank you for this opportunity to review and comment and for your cooperation.

Sincerely,, p Brian D. onway State Historic Preservation Officer

BDC:JRH:ROC:ktj DEPARTMENT OF THE ARMY DETROIT DISTRICT, CORPS OF ENGINEERS 477 MICHIGAN AVE. DETROIT, MICHIGAN 46226-2550

NOV n 3 ?.OH IN REPLY REFER TO: Executive Office Project Management

Brian Conway, State Historic Preservation Officer State Historic Preservation Office Environmental Review Office Michigan Historical Center W. Kalamazoo Street, P.O. Box 30740 Lansing, Ml 48909

RE: ER-930113

Dear Mr. Conway,

The U.S. Army Corps of Engineers, Detroit District (USACE) has additional information regarding the rehabilitation of the West Neebish Channel Rock Cut Guide Walls. This project was previously coordinated with your office on August 10, 1999, October 26, 1999, and November 29, 1999 (Attachment 1 through Attachment 3). The purpose of this letter is to coordinate additional project information with your agency pursuant to Section 106 of the National Historic Preservation Act.

Previously, the USACE had agreed to implement your office proposed alternative of grouting the existing ashlar wall and recessing the outer surface of the grouting from the wall face to a distance that will render it as minimally visible as possible on 1 00 feet of the east (mainland) wall and the 200 feet on the west (island) wall. Additionally the USACE agreed to share the results of this test case with your office and to further coordinate prior to any additional rehabilitation of the structure (Attachment 2). The USACE determined this alternative would result in "no adverse effect" to the historical character of the structure under 36CFR800.5 (b). Your office concurred with this determination (Attachment 3).

The USACE conducted the grouting test repair on 100 feet of both the mainland and island walls in 2000. The grouting repair was determined to be unsuccessful, however, as the grout was either washed away by the strong currents through the rock cut or was absorbed by the surrounding soil.

With grouting being unsuccessful, the USACE evaluated using new stone material to repair the rock cut walls. The USACE determined that rebuilding the wall using new stone would cost approximately 22 million dollars. That amount of funding could not be obtained given budget constraints. 2

Because of the failure of the grouting test, the extensive costs associated with repairing the structure with new stone material, concerns over public safety and the increasing hazard to navigation, the USACE was compelled to proceed with a previously evaluated alternative: a sloped rip rap wall from +7 Low Water Datum (LWD) to -4 LWD (or bedrock)(Attachment 6, Photo 9 and 10) .

By the time the installation of the sloped rip rap wall was initiated approximately 46% of the 4,965' mainland wall had fallen into the river. The USAGE completed the sloped rip rap repair to approximately 4,880' of the wall in 2014 (Attachment 4). Approximately 85' of the mainland wall remains undisturbed due to the good condition of the existing wall and the presence of a United States Coast Guard Navigation Aid at that site.

The USACE has not repaired the island wall; however, approximately 2,302' or about 46% of the existing wall has completely failed and fallen into the water (Attachment 5 and 6, Photo 11 and Photo 12). The USACE believes that the remaining portion of the wall has been mostly undermined and could fail at any time (Attachment 6, Photo 13). The continuing failure of the island wall presents an increasing risk to public safety and a hazard to vessels using the West Neebish Channel Rock Cut.

The USACE acknowledges that the sloped rip rap wall alternative, while discussed in the coordination that took place in 1999, was not the preferred alternative of the Michigan SHPO (Attachment 1) . The decision was made by the USACE to install a sloped rip rap wall based on the extent of the wall lost since the initial coordination in 1999, the inability to effectively implement the grouting alternative, and the hazard wall loss presented to navigation. The USACE continues to agree with the Michigan SHPO that the West Neebish Channel Rock Cut is eligible for the National Register of Historic Places, and we regret our failure to finish the Section 106 process prior to taking action.

Summary and Proposed Action

The rock cut walls have failed and been rebuilt multiple times since the rock cut construction started in 1902 (Attachment 6, Photo 1 and 2) and was opened to downbound sh ipping in 1908. The rock cut channel was deepened in 1932, during which large portions of the rock walls were rebuilt (Attachment 6, Photo 3 and 4). The channel was deepened again in 1960 and again large portions of the rock walls were rebuilt (Attachment 6, Photo 5 and 6). In 1977 further repairs were attempted using precast concrete blocks but by 1996 the repair had failed (Attachment 6, Photo 7). The USACE further attempted to use steel frames and anchor weights to repair the walls by concreting the blocks in place (Attachment 6, Photo 8) which were also unsuccessful.

The rock walls were not designed to current engineering standards and even after being rebuilt twice and repaired numerous times they still are not strong enough for continued use. The original design allows water to exist between the blocks at and below the waterline. The freeze/thaw of the water between the blocks is one of the causes for failure of the rock walls. Additionally, further strain is placed on the wall by friction caused when ice forms within the rock cut. This strain is exacerbated and causes further deterioration 3 when the ice is broken by ice cutters and then pushed against the wall by vessels transiting the rock cut.

Due to the history of multiple wall failures and the failure of grouting and various other repair attempts, the USAGE has determined that it is no longer feasible to continue maintaining the rock cut walls via reconstruction. Their continued failure is due to inadequacy in the original design and they will continue to fail regardless of how many times the walls are rebuilt. In order to maintain the rock cut into the future and remove the threat to navigation the USAGE is proposing to remove the existing rock cut walls sections that have not yet failed on island side, and implement the sloped rip rap wall alternative previously used on the mainland side of the West Neebish Channel Rock Cut.

The USAGE has determined that the implementation of the action on the mainland side of the rock cut and the proposed implementation of the same action on the island side of the rock cut, under 36CFR800.4, has had and will have an "adverse effect'' on the West Neebish Channel Rock Cut. We request your concurrence with this determination.

To mitigate the adverse effect of the already implemented and the proposed portion of this action the USAGE is proposing to retain approximately 85 feet of the original stone wall on both sides of the rock cut. These sections will provide an example of how the rock cut walls appeared when the rock cut was opened to shipping in 1908. Additionally, the USAGE maintains that while removal of the rock cut walls is not ideal from a historic preservation stand point, the West Neebish Channel Rock Cut itself retains its eligibility for the National Register of Historic Places under Criteria A as the quality that makes the rock cut eligible, its effect on shipping in the Great Lakes region, remains intact. With this proposed mitigation the USAGE is interested in continuing the Section 106 process with your office to obtain your concurrence and resolve these issues this winter before the shipping season begins in March 2015.

In addition to your office, the Advisory Council on Historic Preservation will also be contacted regarding our determination. Any questions regarding this project can be directed to Mr. Curtis Sedlacek, District Archeologist, Environmental Analysis Branch (313-226-3510), or myself at 313-226-2240.

Sincerely ~o~t~ Deputy District Engineer for Project Management

Enclosures DEPARTMENT OF THE ARMY DETROIT DISTRICT, CORPS OF ENGINEERS 417 MICHIGAN AVE. DETROIT, MICHIGAN 48226-2550

NOV 0 '3 20H IN REPLY REFER TO: Executive Office Project Management

Advisory Council on Historic Preservation Brian Lusher 401 F Street NW, Suite 308 Washington, DC 20001-2637

Dear Mr. Lusher,

The U.S. Army Corps of Engineers, Detroit District (USACE) has additional information regarding the rehabilitation of the West Neebish Channel Rock Cut Guide Walls. This project was previously coordinated with the Michigan State Historic Preservation Office (Michigan SHPO) on August 10, 1999, October 26, 1999, and November 29, 1999 (Attachment 1 through Attachment 3). The purpose of this letter is to notify your agency of an "adverse effect" finding by the USACE under 36CFR800.6 and Section 106 of the National Historic Preservation Act.

Previously, the USACE had agreed to implement the Michigan SHPO proposed alternative of grouting the existing ashlar wall and recessing the outer surface of the grouting from the wall face to a distance that will render it as minimally visible as possible on 100 feet of the east (mainland) wall and the 200 feet on the west (island) wall. Additionally the USACE agreed to share the results of this test case with the Michigan SHPO and to further coordinate prior to any additional rehabilitation of the structure (Attachment 2). The USAGE determined this alternative would result in "no adverse effect'' to the historical character of the structure under 36CFR800.5 (b). The Michigan SHPO concurred with this determination (Attachment 3).

2 alternative: a sloped rip rap wall from + 7 Low Water Datum (LWO) to -4 LWD (or bedrock)(Attachment 6, Photo 9 and 10) .

The USAGE has not repaired the island wall; however, approximately 2,302' or about 46% of the existing wall has completely failed and fallen into the water (Attachment 5 and 6, Photo 11 and Photo 12). The USAGE believes that the remaining portion of the wall has been mostly undermined and could fail at any time (Attachment 6, Photo 13). The continuing failure of the island wall presents an increasing risk to public safety and a hazard to vessels using the West Neebish Channel Rock Cut.

The USAGE acknowledges that the sloped rip rap wall alternative, while discussed in the coordination that took place in 1999, was not the preferred alternative of the Michigan SHPO (Attachment 1). The decision was made by the USAGE to install a sloped rip rap wall based on the extent of the wall lost since the initial coordination in 1999, the inability to effectively implement the grouting alternative, and the hazard wall loss presented to navigation. The USAGE continues to agree with the Michigan SHPO that the West Neebish Channel Rock Cut is eligible for the National Register of Historic Places, and we regret our failure to finish the Section 106 process prior to taking action.

Summary and Proposed Action

The rock cut walls have failed and been rebuilt multiple times since the rock cut construction started in 1902 (Attachment 6, Photo 1 and 2) and was opened to downbound shipping in 1908. The rock cut channel was deepened in 1932, during which large portions of the rock walls were rebuilt (Attachment 6, Photo 3 and 4). The channel was deepened again in 1960 and again large portions of the rock walls were rebuilt (Attachment 6, Photo 5 and 6). In 1977 further repairs were attempted using precast concrete blocks but by 1996 the repair had failed (Attachment 6, Photo 7). The USAGE further attempted to use steel frames and anchor weights to repair the walls by concreting the blocks in place (Attachment 6, Photo 8) which were also unsuccessful.

The rock walls were not designed to current engineering standards and even after being rebuilt twice and repaired numerous times they still are not strong enough for continued use. The original design allows water to exist between the blocks at and below the waterline. The freeze/thaw of the water between the blocks is one of the causes for failure of the rock walls. Additionally, further strain is placed on the wall by friction caused when ice forms within the rock cut. This strain is exacerbated and causes further deterioration when the ice is broken by ice cutters and then pushed against the wall by vessels transiting the rock cut. 3

Due to the history of multiple wall failures and the failure of grouting and various other repair attempts, the USACE has determined that it is no longer feasible to continue maintaining the rock cut walls via reconstruction. Their continued failure is due to inadequacy in the original design and they will continue to fail regardless of how many times the walls are rebuilt. In order to maintain the rock cut into the future and remove the threat to navigation the USACE is proposing to remove the existing rock cut walls sections that have not yet failed on island side, and implement the sloped rip rap wall alternative previously used on the mainland side of the West Neebish Channel Rock Cut.

The USACE has determined that the implementation of the action on the mainland side of the rock cut and the proposed implementation of the same action on the island side of the rock cut, under 36CFR800.4, has had and will have an ''adverse effect" on the West Neebish Channel Rock Cut.

To mitigate the adverse effect of the already implemented and the proposed portion of this action the USACE is proposing to retain approximately 85 feet of the original stone wall on both sides of the rock cut. These sections will provide an example of how the rock cut walls appeared when the rock cut was opened to shipping in 1908. Additionally, the USACE maintains that while removal of the rock cut walls is not ideal from a historic preservation stand point, the West Neebish Channel Rock Cut itself retains its eligibility for the National Register of Historic Places under Criteria A as the quality that makes the rock cut eligible, its effect on shipping in the Great Lakes region, remains intact. With this proposed mitigation the USACE is interested in continuing the Section 106 process with the Michigan SHPO to obtain their concurrence and resolve these issues this winter before the shipping season begins in March 2015.

In addition to your office, the Michigan SHPO will also be contacted regarding our determination. Any questions regarding this project can be directed to Mr. Curtis Sedlacek, District Archeologist, Environmental Analysis Branch (313-226-351 0), or myself at 313-226-2240.

Sincerely S~t~o~~ Deputy District Engineer for Project Management

Enclosures Attachment 1

~~, . . .;;;;;;;;;;;;;;;;;;;.;;;;;;;;;;;;;;;;;;;;;;;;MI;;;C;;;H;;;I;;;;;G;;;AN;;;;;;;;D;;;E;;;P;;:A~R;;T;;;ME;;;;;;;;N;:T~O;;l1;;;S;;;T;A;;TE;;;;;;;;;;;;;;;;;;;;;;;;;;;;=;;;;;;=Candice S. Millei, Secretary of State ' ~ Lansing! Michiga'n 48918-0001 · -- STATE.HISTORIC PRESERVATION OFFICE · Michigan Hlstorical Cclltcr 717. WestAlfegan Street Lansing~ Michi_gan 48918-1800

Au'gus't 10, 1999.

DAVlD,L DULONG. ·. I. 'DEPARTMENT OF THE ARMY I DETROIT DISTRICT' CORP~ OF ENGINEERS BOX 1027 . DETROI'r MI 48231-1027

RE: ER-930 113 Rehabilitation ofNeebish Island Rock Cut Guide Walls, Course 6, West Neebish ii Channe't, St. Marys Rive~·, Chippewa County (CO.E) I lo Dear Mr. Dulong: · " Under th,~ authority of S~ction lOG of the N:ational Historic Preservation Act of 1966, as amended, we have •J reviewed the·above-citcd' undertaking at the location noted ab.ove. Bas~d· on the inforillation provided for_our 1 · review, it is the opinion of the State Historic Preservation Offiqer (SHPO) that all ofthe proposed'altematives will

have an adverse effect on the West Neebish Channel Roqk Cut, which appears to_meet the criteria for listing .itl the • I National Regist~r of_Historic Places. ·

Of the proposed attematives, grouting the existin.g ash1ar wall will cause the -least harrn to the structu~e '~ historic· character and design. This alternative will stil'l have an adverso affect, however, becau·se the limestone ashlar walls ·are not currently mortared. The adverse effect of this alten').ative c~u ld be reduced by recessing the outer surface' of the grouting froin the 'wall face, to·a djstanc'e that will render it little visible possible. . ' - . . . . - . ' - as as . The second best alternative,·in our opii1ion, is the use of quarry stone. Jfwe understand the project correctly, this - method would oontinu~ a manner ofrepair that the Corps has: used for the Roc!( Cut it'! the past-and it will appear somewhat similat to the 'cxisth1g stone ~·as_onry. · ·

1n our opinion, the 1>haped rip rap alternatives will greatly alter the appe'anince and historic. design ·ofthe Wes~ Necbish-Channcl Rock Cut. · · · · .. : · · · ·

The.un'dcrtaking. rrieets the fo llowing criteria of adverse effect outlined in federal regulation 36.CFR:§ 800.5(a)(l): the .fmdertaktng may a!ter, dtrectly or indirectly, any of the characteristics ofr£ historic-property that qualify the properlyfor inclusion in the National Register ih a man11er that would dim(l~ls~ th ~ integrity ofthe property's location., design, setting, l~tat~rials, wor!cinanshiptfeeling, of association. Spcci.fica1ly, the undertaking will result in

• Alteration of @.properly, inclu~ing -restoration , rehabilitation, ·repair, maintenance, stabilization, hazardous material remediation and provision of handicapped access that is not consistent with the Secretary's Stand~rds for the Treatm~nt ofl:Ustoric Properties [36 CFR § 68] and appli cabl~ gu id.elip.es . .. · ~ I· The fmdiog of adverse .effect will prompt the Corps of Engineers, hereinafter' ref-erred to a.s ''Agency", to consult I further to r~solve the adverse effect pursuant to 36 CPR§ 800:6 'by proceeding with the following steps: ·...... I (1) Per 36 CFR ·§ 800.6(a), the Agen.cy shall condnuc consultation with the SHPO 1ind other.consulting parties to I · develop.and evaluate alternatives or modificatidn.~ to the undertaking· tl~at could avoid, minimize or'mitigafe 1:' adverse effects on nistoric·properties. The Agency sh~il submit a case study.outlining these efforts for rcv'iew i by the SHPO...... r· ! (;2) In acc.orda.nce with 36 CFR § 800.6{~)(4)~ the Agency sh a~ l ;nake infonnation regarding.this finding a.vailable to the public, providing the public ·with an opportunity to express th,cil: views on resolving adverse effects ofthe · · · undertaking. Pursuant to 36 CFR § 800'.11(e), copies or summaries ohny views provided by consulfuig parties. and tne public shall be made available· to th~ SHPO as _Parf ofthe case study outlined in (1). ' · i:~ I >!' ) (3) The Agency shall inunediatcly notify the Advisory CouncH on Historid Preservation (Advisory Council), Old I Post Office Building, 1100 Pennsylvania Avenue, NW, Snite 809, Washington, D.C. 20004, of the adverse effect finding [36 CFR § 800.6(a)(l)]. The notification to the Advisory Council sl1ould be similar to the project I information submitted to this office a11d should include the following documentation [36 CFR § 800.11(e)]: ' • A description of the undertaking, specifying the federal involvement, and its area of potential effects, !. including photographs, maps and drawings, as necessary ' ..•.f • A de§oription of the steps taken to identify historic properties . • A description of the affected historic properties, incltlding . i~formation on the 'charactctistics that qualify them for the National Register . . · · • A description ofthe undertaking's perties· • An explanation of why the criteria of adverse _effect we1:e. found. applicable or ina,pplicable, inoludil:tg any conditio~1s or future actiO!JS to avoid, ~inimize or mitigate adverse effects · . · • .Copies or summaries of any views provided by consulting parties and the public .

(4) If the -undertaking will affect aNational Historic Landmark, \fa progra@11atic agreement will be developed· as ~~ resttlt of the finding of' adverse ef~ct, or if it so desires, ·the Agency may u.se the opportunity. to notify :tl1c . · . Advisory Council ofthe adverse effect fmding to invite the Advisory Council to participate in consultation. ·The Advisory Council wi.ll advise of its de~ision to partic.ipate irt consultation withtn fifteen (15) days of re.ceipt of this notification or other request. If the Advisory CounciL chooses not 't~ participate in co n ~ultation, the Agency shall resolve. the adverse·effect without Advisory Council participation. . and pursuant to 36. CFR § '800.6(b)(l .

(5) Ifthe Agency, the. Slll)O and (if applicable) .the AdvisorY. Council agree on howthe . adv~r-s~ effects·:wifi be resolved, they sl1all execute a Memorandum of Agreement (MO'A) pur~uant to 36 CFR § 800.6(c). ·

(6) ·If the Age~cy and the S~':IPO fail to agree on the terms of.a MdA, the Agency shall r~qu est the Advisory Council to join the. corisult.atio~. If tho Advisory Council decides to join the consultation, the Agency shall proceed in accordance with 3 6 CFR § 800.6(b)(2)." If the Advisory Councll decides not to join the 'cons'ultatiot'l, the Advisory CoJJncil will notify thy Agency and proceed to comment in -' a~cord.ance with 36 CPR§ 800.7, "Failure.to resolve adverse e.ffects".

While consultation with the SHPO must continue for tbe selection of a preferred alternative, we concur with the Corp's proposal to mitigate the .adverse effect throug11, at a minimum, recordation of the existing Rook Cut.

I l ! I ; 0

The State' Historic Preservation .Offio~ is not the office of record· for this undertak~qg . You are therefore asked to maintain ·a: copy 'of thiG letter with your,.environmentalt·eview 1·ecord for this _und~rtal~ing. If the scope of w·ork changes in any way, or if. artifacts or: bones are discqvered, please. notify this office immediately.. . flease note that the Section roo process will not.be corhplcted until tho consulf~tion proce.ss is compl~te, a !, . Memorandum of Agreement is develop~d . executed and.impJementcd, and, if applicable, the- fohnal comments 'of the'Advisory Cquncil have ~ecn received. · .., I · If you hav·e any· que s~ions , plea~e contact Mar_*a MacFarlan~; EnvironmeJ;ltal -R~v i ew c'o~rdi:na tor: .at (S 17) 335- l j 2 721. Th~nk,:. y~~l -fo~ this ~_p.porf!.mi ty.to reyie_"Y a_n4.o _~~~f(t:l~ ~nq for yo-qr .~99peration . .. " . .

Brian D. onway State Historic Preservation fficer t. BDC:JR.H:ROC:krj

cc: . Advisory- . Council. . -on.. Historic . . .Preserva ·tion

- . .:

• r

:·. Attachment 2 OCT 2 6 1999

Engineering & Planning Division Environmental Analysis Branch

Mr. Brian Conway · sta:t·e Historic Preservation Officer Michigan Department of State 717 W. Allegan Lansing, Michigan 48918

Dear Mr. Conway:

Sincerely,

~;7/ft-- David L. Dulong, P.E. hief, Engineering & Planning Division Attachmen.t 3 ~ I MICIDOAN DEPARTMENT OF STATE Candice S. Millel-. Secretary ofState I~ I Lansing, Michigan 48918-0001 I . ! STATE HISTOIUC PRESERVATION OFFICE Michigan Historical Center 717 West Altegun Street Lansing, Michigan 48918-1800

November 29, 1999

DAVID L DULONG DEPARTMENT OF THE ARMY · DETROIT DISTRICT CORPS OF ENGINEERS BOX 1027 . DBTI?.OlT MI 48231-1027

RE: ER-930113 Test of Rehabilitation Alternative for Nccbish Island Rock Cut Guide Walls, Course 6, West Neebisb Channel, St. Marys River, Chippewa County (COB)

Dear Mr. Dulong:

Under the authority of Section 106 of the National Historic Preservatio11 Act of 1966, as· amended, we have tcvicwed the above-cited undertaking at t,hc location noted above. Based on the information provided for our review, the State Historic Preservation Officer (SHPO) concurs with the determination ofthe Corps of Engineers that the effects ofth e proposed undertaking does not meet the criteria of adverse effect outlined in the federal regulation 36 CFR § 800.5(a)(1). Therefore, the project will have no adverse effect [36 CFR § 800.S(b)] on the West Nccbish Channel Rock Cut, which appears to .meet the criteria for listing in the National Register of .Historic Places. •, The State Historic Preservation Office is not the office ofrecord for this undertaking. You are therefore asked to ' maintain a copy of this letter with your environmental review record for this undertaking. If the scope of work changes in any way, or if artifacts or bones are discovered, please notify this office immediately.

If you have any questions1 please contact Martha MacFarlane, Environmental Review Coordinator, at(~ 17) 335- 2721. Thank you for this opportunity to review and comment and for your cooperation.

Brian D . onway State Historic Preservation Officer

BDC:JRH:ROC: ktj Attachment 4

Island Wall (to remain intact) Mainland Wall (to remain intact) o--- Island Wall (Proposed Slope Area) - Mainland Wall-Sloped (completed 2014)

990-=4]9•5•=0••••••990 Feet Date: 9/5/2014 A 1 Produced untl• r llo•n11 rrom ESRI Attachment 5

Island Wall Photo Locations (approximate) • ·-- Failed Sections of Island Wall (approximate)

N 750 375 0 750 Feet

A llnag• pfoductd lR:Ier llc:enu from ESRI OltO: 9117/2014 Attachment 6

Photo 1-1902 Original Construction

Photo 2 ~ 1902 Original Construction -·------·------·------

Attachment 6

Photo 3-1932 Before Deepening Started

Photo 4-1932 Deepening (Walls being reconstructed) - ~--~------~~~-~~

'I.

Attachment 6

'lT. MAI!Y~·II\VMt, 9AUI.1'.~1·r·:, IIAHJH, t.l\<;tt,, nh'l'llOJ'\'l)tWt'fltl;'l' Hf.PAIJtS 'J'O 011'1. 111> 'II'A I ,I.~ , c;nHtii•C'I' KO. J'IA•2 0·0G1 -~JV£NC-60·\l 7 , Tfli\YT .on 111101'H I·ll~, JNC ,.COI~ ll!AC'll'lll WOI(Tl\'U HOI'1ll tROt.! f;, :l • GG-•00 , Ji<'lti~l\0 \?M,r, lllll'ATll 19 Oc:'!OO! II l!)GO

Photo 5- 1960 Deepening-Walls being repaired "

Attachment 6

f· I I 1~..I ~·

t I·

l. r I BT. MARYS RlVI!Il , BAVJ,T 8'1'1< . IIARH , MI CH, , !>f,TROIT UI WrRH r \I c.9. ea.oo - 70+00 lfll·" ovum wAJ.L - nn Kl!lliJ ~

Photo 6-1 960 Photo Showing West wall being repaired Attachment 6

ST. MARYS RIVER, WEST NEEBISB Oil\NNEL c.s. 63+50 EI'.ST GUIDE WALL, RCCK OJT 8 .JUNE 1.977 (L.'-" { ._..-PAort.) PJH>-foj.-../'1, Nc. Z... I!Pf'ei'>.)/)IX A. A - 9

Photo 7-Background photo is from 1977, showing an attempted repair on the wall. Foreground photo is from 1996 showing the failure of that repair

G Attachment 6

l.· I

I·

Photo 8. Looking south along west wall as approx. Station 40+00 (July 24, 1996). Concrete repair was accomplished with the steel form and anchor weights, as shown. Repair failed. I'

Attachment 6

Photo 9- Mainland side of rock cut after side slope alternative has been implemented (looking north)

Photo 10-Mai nland side of rock cut after side slope alternative has been implemented (looking south) Attachment 6

Photo 11- Example of island wall failure (September 2014)

Photo 12-Example of island wall failure (September 2014) Attachment 6

r-·

Photo 13-Example of early stages of wall failure (September 2014) Attachment 6

Photo 1-1902 Original Construction

Photo 2-1902 Original Construction Attachment 6

Photo 3-1932 Before Deepening Started

Photo 4-1932 Deepening (Walls being reconstructed) Attachment 6

Photo 5- 1960 Deepening-Walls being repaired

Attachment 6

Photo 6-1960 Photo Showing West wall being repaired

Attachment 6

MARYS RIVER, WEST NEEB ISH Qll\N'NEL c .s . 63+50 EAST I)( A A-9

Photo 7-Background photo is from 1977, showing an attempted repair on the wall. Foreground photo is from 1996 showing the failure of that repair Attachment 6

Photo 8. Looking south along west wall as approx. Station 40+00 (July 24, 1996). Concrete repair was accomplished with the steel form and anchor weights, as shown. Repair failed.

Attachment 6

Photo 9- Mainland side of rock cut after side slope alternative has been implemented (looking north)

Photo 10-Mainland side of rock cut after side slope alternative has been implemented (looking south) Attachment 6

Photo 11- Example of island wall failure (September 2014)

Photo 12-Example of island wall failure (September 2014) Attachment 6

Photo 13-Example of early stages of wall failure (September 2014)