17264 Cheboygan Lock Downstream Wall Replacement - Addendum 2.pdf

ADDENDUM NO. 2

A2-2000-1

CHEBOYGAN LOCK DOWNSTREAM WALL REPLACEMENT PROJECT DTMB FILE NO. 751/17264.ABG

File No.: 751/17264.ABG Department of Natural Resources

Project Name: Cheboygan Lock Downstream Wall Replacement Project Subject: Request for Bids – Addendum 2

DATE: August 8, 2025

BID DATE: Wednesday, August 13, at 2:00 p.m. Eastern Time

TO: All Bidders

INTENT: This Addendum is issued to revise and clarify the intent of the project bid documents.

ATTACHMENTS: 1. Question Responses

2. Revised Drawings and Specifications

3. Revised Project Manual Articles

All Bidders submitting a Bid on the above Contract shall carefully read this Addendum and give it consideration in the preparation of their Bid.

Contractor shall list all addenda on the Bid Form to ensure conformity in the bid.

Drawings, Specifications and/or Proposals are herein amended, expanded and/or modified, as hereinafter described, and become a part of the Contract Documents with same force and affect as if incorporated, therein, originally. Any contrary provisions contained, or referred to, in Drawings and/or Specifications, shall remain applicable unless overridden by this Addendum.

Revised or contrary provisions herein shall not affect any other part of Contract Documents and any deletions, additions, substitutions and/or revisions mentioned, shall include all labor, materials, methods, modifications, etc. required for complete performance of the work.

The following are revisions to the Bidding and Contract Requirements:

GENERAL:

1. Questions List

DRAWINGS & SPECIFICATIONS:

1. 02645 Drilled Soldier Pile and Lagging Wall

2. 13440 Geotechnical and Structural Instrumentation (Remove from scope)

PROJECT MANUAL:

1. Revised Schedule of Alternates

2. Revised Schedule of Change Order Prices

ADDITIONAL KEY INFORMATION:

1. None

Bidder shall acknowledge receipt of this Addendum at the bottom of the Bid Summary form to be submitted as part of the greater bid.

A2-2000-2

ATTACHMENT 1 TO ADDENDUM NO. 2

SUMMARY

This Attachment 1 to Addendum No. 2 provides all bidders with questions to be answered. The questions in the following table have been received and answered by the Engineer.

Cheboygan Lock Downstream Wall Replacement Project - Addendum #2 Question Responses

ITEM DOCUMENT SECTION QUESTION RESPONSE

Column1 Column12 Column13 Column2 Column3

0001 SPECIFICATIONS 03500

The Drilled Soldier Pile and Lagging Wall Specification 02465 Section 3.02.H indicates, “Place tremie concrete in approximately 3-foot lifts, vibrating with each lift placement.”

However, the Tremie Concrete Specification Section 03500 Section 3.01.K indicates, “In smooth motion, lift the concrete pipe no higher than 6 inches to allow the concrete to push out the seal plug and then pump high slump concrete through the tremie pipe without interruption to completely fill the base of the bedrock pocket in one continuous operation without interruption by means of tremie methods.”

Please verify we are not required to tremie place 3-foot lifts and vibrate the concrete in lifts.

It is not required to place the concrete in 3-foot lifts during the tremie process. The procedure described by the Tremie Concrete Specification Section 03500 is correct and supercedes the errant Specification 02465 Section 3.02.H.

0002 PROJECT MANUAL

03000

ARCTICLE 6

During the pre-bid it was stated that alternative wall replacements would be considered, and should be listed as alternates on the bid submission. Please update the bid schedule form and list required documents or information that will need to be submitted with any proposed alternate, including verification that proposed alternates will be maintained in strict confidentiality and not shared with other bidders or reused for future project solicitations. Can an updated bid schedule form and clarifications be provided?

See the revised bid schedule form allowing for value-engineered alternatives. Note, any value-engineered alternative wall replacement concepts will be accepted only where the Contractor can provide proof of concept and feasibility with their bid. Clarifications and additional detail may be requested during the interview process. If accepted, complete design detailing, calculations, and analyses by a Michigan Professional Engineer will be required during the submittal process. Any supporting information submitted for a proposed value-engineered alternative will be viewed as proprietary and confidential and will not be shared with other bidders, nor reused for future project solicitations, during bid review and assessment. Note, some information may be required to be available to public inquiry by law once a project has been awarded.

0003 DRAWINGS G-03 During the pre-bid it was stated that alternative access options would be allowed.

Alternative access means may be allowed at the discretion of the Owner. Note, any access requiring additional fill or impacts to sensitive resources (floodplain, waterbodies, etc.) not already accomodated by the Joint Permit would be subject to filing and approval of a Joint

Permit amendment with EGLE and USACE.

0004 PROJECT MANUAL

00100

ARTICLE 14

During the pre-bid it was stated that the DNR/GEI intended to perform interviews with respondents. Is this a low bid solicitation or a best value proposal?

The Contract will be awarded, in accordance with Article 14 of the Project Manual, to the responsive and responsible best value bidder (except as provided relative to veteran’s preference). The bids will be evaluated for best value by comparing the price and qualitative components of the three lowest responsive and responsible Bidders.

0005 PROJECT MANUAL

00210

Section 5.0 Will the contractor be required to procure any USACE or EGLE permits?

The Owner has an approved Joint Permit through USACE and EGLE for completion of the work (and other scope, some of which has since been removed from the scope of this project) from 2023 as provided in Addendum #1. The approved permit does not include the temporary fill work pad, which is currently under review under a permit amendment. It is not anticipated that the Contractor should be required to procure any USACE or EGLE permits for the base scope of work, unless an alternate access means would be cause for additional impacts to resources under such jurisdiction.

0006 JOINT PERMIT -

Are there any in water work restrictions from EGLE/DNR/USACE or other entities during the proposed work periods?

All staging of equipment, materials, and work items must occur outside the USACE navigable channel, except for during active transport to and from the site.

0007 SPECIFICATIONS 02465

How will pile drilling depth be determined in the field? Is the contractor required to provide a

Professional Engineer to verify pile embedment in suitable ground conditions?

The Contractor will be responsible for their own Quality Control including layout, measurement and verification of pile location and depth. However, a qualified GEI field representative will be onsite to perform Quality Assurance testing and verification including confirmation that the subsurface conditions encountered meet the design intent for the piling. The Contractor is not required to provide an independent Professional Engineer to verify suitable ground conditions.

Page 1 of 2 8/8/2025

Cheboygan Lock Downstream Wall Replacement Project - Addendum #2 Question Responses

ITEM DOCUMENT SECTION QUESTION RESPONSE

Column1 Column12 Column13 Column2 Column3

0008 PROJECT MANUAL

03000

ARCTICLE 7

The drawings state 20’ minimum socket depth for drilled piles. How will payment for addition drilling depth and splicing of piling be handled?

The design intent is to install piling to a minimum depth of 20 feet below top of glacial till. The

Contractor should be prepared to install each piling up to 25 feet below till without cause for additional compensation. In the event piling are required to extend beyond the 25 feet depth, the Contractor shall immediately notify the Engineer and, upon written approval to proceed, continue to the acceptable termination depth. Payment will be provided in accordance with the revised Article 7 of the Project Manual. Please provide unit pricing for pile splicing (each) and additional piling depth (linear foot) including all materials, equipment, labor, and ancillary components for complete installation. The splicing is anticipated to be performed with splice plates on each side of the HP web, with each splice plate welded with a fillet weld all around.

0009 DRAWINGS SHEET C-04

Detail 2/S-07 is the sheet pile required to be welded to the HP12x120? Or is it just contact bearing?

The sheet piling is anticipated to be in bearing against the HP members. No welding of SSP to

HPs is anticipated.

0010 DRAWINGS SHEET C-04

Detail 3/S-07 shows welded steel shim plates where required. What is the vertical height requirement or contact area of shim to sheet pile and shim to Hpile?

Each shim shall provide a minimum of 12" of vertical contact between SSP and HP flanges.

0011 SPECIFICATIONS 02465

Please confirm no timber lagging is intended anywhere on the project, sheet pile “lagging” is bearing against the piling?

Correct, the term "lagging" refers to the steel sheet piling between HP piling. There is no timber "lagging" on the project. Note, however, there are several veritcal timber fenders to be fastened to the piling to protect against boat impacts.

0012 JOINT PERMIT -

The EGLE permit provided in addendum 1 appears to authorize different work scope. Please provide the correct permit or state the location where this work is to be performed, or clarify this is a permit amendment and confirm the permit does not define any work scopes outside of the project drawings?

The Owner has an approved Joint Permit through USACE and EGLE for completion of the work which includes additional scope items which have since been removed from the scope of this project. The current approved permit and the permit amendement quantities have been provided in Addendum #1 as requested during the pre-bid for bidder reference. The current approved permit does not include the temporary fill work pad, which is currently under review under a permit amendment. The permit amendment also removes the scope indicated by the approved permit which is not to be included in the scope of this project (gabion baskets, slab grouting, etc. shown for reference for impact quantities only).

0013 DRAWINGS SHEET C-03 Is any dredging work anticipated prior to riprap placement? No dredging prior to placement of any temporary nor permanent rip rap is anticipated.

0014 DRAWINGS SHEET C-03 Is grout beneath the existing slab required? No grouting beneath the existing slab is required.

0015 PROJECT MANUAL

03000

ARCTICLE 6

The current proposal form 6.2 schedule of alternates defines “barge only access” as alternate

1 and is listed as a deduct. Please remove the word deduct as barge only access will not deduct but will add cost to the project?

The schedule of alternates errantly listed the barge access as a deduct - this has been revised to indicate the barge only access to be an add alternate.

0016 JOINT PERMIT -

Please confirm anticipated NTP and anticipated permit authorization date, and confirm if the contractor will be held responsible for liquidated damages if NTP and permit authorization are not received by said date.

The successful bidder is anticipated to be provided a notice to proceed by October 10, 2025.

The Joint Permit amendment is anticipated to be approved by September 26, 2025. In the event that either of these dates are not met, the Contractor will be issued a Bulletin confirming the appropriate modifications to the substantial completion date. The substantial completion date will be equivalently delayed by the delay in project schedule. Liquidated damages will be assessed in accordance with the revised substantial completion date. Note, if the Owner elects to accept Alternate 1 (performing the work with barge access and removing the temporary fill scope) and the notice to proceed date is met, the substantial completion date will not be adjusted and liquidated damages would be assessed for work not meeting the current prescribed date.

Page 2 of 2 8/8/2025

A2-2000-3

ATTACHMENT 1 TO ADDENDUM NO. 2

END OF ATTACHMENT

A2-2000-4

ATTACHMENT 2 TO ADDENDUM NO. 2

This Attachment 2 to Addendum No. 2 provides all bidders with the following revised Specifications:

1. 02645 Drilled Soldier Pile and Lagging Wall

a. Removed reference to errant 3-feet lift requirement for placement of tremie concrete.

2. 13440 Geotechnical and Structural Instrumentation

a. Removed from scope. Owner will work directly with PSC to provide monitoring of adjacent building.

Drilled Soldier Pile and Lagging Wall - Issue For Bid – Addendum #2

Michigan Department of Natural Resources – Cheboygan Lock Downstream Wall Replacement

GEI Project No. 1904013 1 Section 02465

SECTION 02465

DRILLED SOLDIER PILE AND LAGGING WALL

PART 1 GENERAL

1.01 WORK INCLUDES

A. Furnishing all materials, equipment, supervision, labor, and services for installation of the soldier and pile and lagging (SPL) wall, as shown on the Drawings and as specified. The

Work includes, but is not limited to:

1. Performing excavation and backfilling to the grades shown on the Drawings.

2. Fabricating and furnishing the soldier piles.

3. Drilling holes for the soldier piles and the concrete shafts surrounding the lower portion of the piles.

4. Installing the soldier piles in the drilled holes, pouring the concrete caissons to the specified elevations, and backfilling the remainder of the drill hole with embankment fill as specified in Section 02320 – Backfill.

5. Installing the continuous sheet pile lagging wall to the depths indicated on the drawings and in the specifications.

6. Taking all necessary precautions to protect adjacent structures and facilities from damage during construction.

1.02 RELATED SECTIONS

A. The following items of related work are specified and included in other Sections of this

Specification:

1. Section 02100 – Building Condition Survey

2. Section 02315 – Excavation.

3. Section 02320 – Backfill.

4. Section 03500 – Tremie Concrete.

5. Section 05100 – Structural Steel.

6. Section 13440 – Geotechnical and Structural Instrumentation

1.03 REFERENCES

A. The following is a list of standards that may be referenced in this Section:

1. ASTM International (ASTM):

a. ASTM A572 – Standard Specification for High-Strength Low-Alloy

Structural Steel.

GEI Project No. 1904013 2 Section 02465

2. American Institute of Steel Construction (AISC) Steel Construction Manual, 14th

Edition.

3. Where these Specifications differ from the requirements of ASTM, the more stringent requirements shall apply.

1.04 SUBMITTALS

A. Installation Procedures:

1. Submit a workplan with the following information to the ENGINEER for acceptance a minimum of 14 days prior to beginning the work activity.

2. Submit proposed layout and sequence of operations, including:

a. Method for job site access:

1) This includes stable working platform for drilling, and pile installation equipment.

2) Stable working platform for pouring concrete.

3) Concrete pouring/pumping plan, which will allow concrete to reach its destination and be poured in a timely manner.

b. Installation of soldier piles.

c. Installation of continuous sheet pile wall:

1) This must include a contingency plan for removal of obstructions that impede sheet pile installation approved by the ENGINEER.

d. Excavation of soil between new and existing wall following construction of the new wall, and prior removal of the existing wall as specified in

Section 02315 – Excavation.

3. Proposed equipment and methods for drilling and backfilling caissons for the soldier piles, including drill hole diameter, method of advancing the drill hole, method of maintaining a stable drill hole, and method of handling and disposing of drilling fluid and cuttings.

B. Flowable Fill:

1. Submit proposed flowable fill mix design for the backfill above the concrete shaft.

C. Shop Drawings:

1. Submit drawings showing complete details of the soldier piles and all welded connections.

D. Test Certificates:

1. Submit mill certifications for wide flange sections and angles.

GEI Project No. 1904013 3 Section 02465

1.05 GENERAL REQUIREMENTS

A. The CONTRACTOR is responsible for planning and constructing a temporary working platform or barge in the existing channel as required for access of the CONTRACTOR’s proposed construction equipment and the CONTRACTOR’s proposed sequence of work.

B. Coordinate with OWNER to locate all underground utilities and structures near the work prior to any excavation or drilling for soldier piles.

C. The CONTRACTOR shall perform the building inspection of the adjacent Great Lakes

Tissue Power Plant per Specification Section 02100 – Building Condition Survey prior to beginning any work related to the drilled soldier pile and lagging wall.

D. The CONTRACTOR shall install and monitor the vibration monitoring program at the adjacent Great Lakes Tissue Power Plant per Specification Section 13440 – Geotechnical and Structural Instrumentation prior to beginning any work related to the drilled soldier pile and lagging wall.

E. The drill holes for the soldier piles are anticipated to encounter extremely dense soils as identified in the historical borings. CONTRACTOR to mobilize appropriate drill rig and equipment to advance the holes in these conditions.

PART 2 PRODUCTS

2.01 SOLDIER PILES AND SHEET PILE LAGGING

A. Uncoated HP Sections shall be new HP12x102, ASTM A572 – Standard Specification for High-Strength Low-Alloy Structural Steel, Grade 50.

B. Uncoated Sheet Pile shall be new NZ 21, ASTM A572 – Standard Specification for

High-Strength Low-Alloy Structural Steel, Grade 60, or equivalent hot rolled sections exhibiting a minimum of the following:

1. Minimum thickness of 0.433 inches.

2. Minimum moment of inertia 313.4

3. Minimum Section Modulus 38.69

4. Sheet pile shall be full length sections of the dimensions shown on the Drawings.

5. Sheet pile interlocks shall be free-sliding, provide a swing angle suitable for the intended installation but not less than 5 degrees when interlocked, unless otherwise designated on the Drawings. Must maintain continuous interlocking when installed.

6. Store and handle sheet piling in the manner recommended by the manufacturer to prevent permanent deflection or damage to the interlocks. As a minimum, support on level blocks or racks spaced not more than 10 feet apart and not more than 2 feet from an end.

C. Concrete Caisson: Concrete Mix as specified in Section 03500 - Tremie Concrete.

GEI Project No. 1904013 4 Section 02465

D. Casing: Casings shall be steel or other suitable material of sufficient strength and stiffness to resist any earth pressures that may occur. The diameter and length of the casings shall be suitable for constructing the caissons to the size and depth and at the locations shown on the Drawings.

PART 3 EXECUTION

3.01 PREPARATION

A. Coordinate with OWNER to locate all underground utilities and structures near the work prior to any excavation or drilling for soldier piles.

3.02 INSTALLATION

A. Install the SPL wall in a manner that prevents excessive movement, settlement, loss of ground, or damage or movement to adjacent structures and utilities.

B. Pile locations shall be laid out by a Professional Surveyor license in Michigan. All components of the SPL wall shall be confirmed to be located on property owned by the

Michigan Department of Natural Resources prior to installation.

C. Determine the design locations of the soldier piles by field survey and use a template at working grade to maintain proper alignment of the piles during installation. Confirm field conditions and wall fit up before beginning construction. Any necessary changes to wall alignment, spacing, etc. due to conflicts shall be confirmed by the ENGINEER.

D. Install the soldier piles in drill holes advanced with auger or rotary equipment. Provide temporary casing and/or drilling fluid as required to maintain stability of the drill hole.

Do not drive soldier piles. Brace soldier piles as necessary upon completion of installation.

E. Prevent undermining of nearby existing structures.

F. Verify that the drill hole is stable and open to full depth before placing concrete. If any collapse of the drill hole occurs, remove the soldier pile, and redrill the hole.

G. Use concrete tremie pipes to prevent concrete segregation during placement. Water infiltration is expected, and placement of concrete should be planned accordingly.

H. Place tremie concrete in approximately 3-foot lifts, vibrating with each lift placement.

I. Coordinate temporary casing withdrawal carefully with concrete placement. When temporary casing is being withdrawn, maintain a sufficient head of concrete from above the bottom of the casing to prevent reduction in the shaft diameter due to earth and/or hydrostatic pressures on the fresh concrete, and to prevent extraneous material from mixing with fresh concrete. Check the concrete levels in the temporary casing prior to, and after casing withdrawal to confirm that separation of the shaft concrete has not occurred.

J. Fill the drill hole with concrete up to the top of caisson elevation shown on the Drawings.

K. Protect fresh concrete from flowing water and damage from mechanical equipment and nearby construction vibrations. Vibration from construction operations (vibratory casing

GEI Project No. 1904013 5 Section 02465 installation, etc.) are not permitted within a radius of 25 feet until the concrete has attained 75 percent of its specified minimum strength. Protect concrete from strength reduction caused by heat, frost, or freezing actions.

L. Do not leave uncased drill holes open for more than 36 hours.

M. No excavation shall occur until the caisson concrete has reached its designed strength

(i.e., 21-day strength). Excavations shall not be deeper than elevations shown on the

Drawings.

N. Upon completion of installation of the drilled in-place HP piling to El. 550 or deeper and cure of tremie placed CLSM, drive SSP to a target El. of 570 using variable moment vibratory hammer with adequate penetration rate without overheating the interlocks (<

450 deg. F). If specified tip elevation is not achieved with vibratory hammer, all SSP shall be advanced to El. 568.5 or deeper using a minimum 30,000 ft-lbs hydraulic or diesel operated impact hammer to achieve a practical refusal (defined as 20 blows/per inch at the full rated impact hammer energy level for the last 2 inches of driving).

O. Vibratory hammer shall be able to operate in zero displacement amplitude until desired frequency has been achieved. The intent is to limit low frequency vibrations during start up and shut down of the hammer.

P. Maintain driving hammers in proper alignment during driving operations.

Q. If obstructions restrict driving a pile to specified penetration, the CONTRACTOR shall remove the object as stated in the installation procedure submittal and approved by the

ENGINEER.

R. Align and plumb the first two sheets and drive carefully and accurately.

S. Sheets being driven above concrete caissons shall be driven to top of caisson elevation.

Take care to avoid excessive vibrating of sheet pile on top of concrete caisson.

T. Sheets being driven between concrete caissons shall be driven to a minimum depth of 1.5 feet below caisson elevation, or to top of glacial till as defined by SSP refusal (defined as

20 blows/per inch at the full rated impact hammer energy level for the last 2 inches of driving).

U. Piles shall be interlocked throughout the entire wall length to ensure a continuous diaphragm.

V. Once installation of sheet piles is complete, soil between the new and existing wall shall be excavated. Excavations shall not be deeper than elevations shown on the Drawings.

W. Cut off top of piles to elevation shown in the Drawings. Trim deformed pile heads.

3.03 CONSTRUCTION TOLERANCES

A. Soldier Pile and Lagging Wall Tolerances shall meet manufacturers specifications.

B. Horizontal Alignment: Ensure the drilled shaft actual centerlines are within 2 inches of plan centerlines at the plan elevation for the top of the shaft. The pile must be within 1 inch of the plan centerline at the plan elevation from the top of the spile.

GEI Project No. 1904013 6 Section 02465

C. Plumb: At the drilled shaft actual bottom elevation, ensure the out of plumb is no greater than 1 percent of the drilled shaft length as measured from the actual center of the shaft at the shaft design top elevation. For the pile, ensure that the out of plumb is no greater than

1/8 inch over 3 feet.

D. Top of Shaft Elevation: Ensure the top elevation of the shaft is within + / - 1 inch from the plan top of shaft elevation.

E. Drilled shaft elevation and completed shafts not constructed within the required tolerances will be considered unacceptable. The CONTRACTOR must correct all unacceptable shaft elevations and completed shafts to the satisfaction of the owner and engineer. Materials and work necessary to complete the corrections for the out of tolerance drilled shafts, including engineering analysis and redesign, will be at the

CONTRACTOR’S expense, and without an extension of the completion dates for the project.

END OF SECTION

Geotechnical and Structural Instrumentation - Issue For Bid – Addendum #2

GEI Project No. 1904013 1 Section 13440

SECTION 13440

GEOTECHNICAL AND STRUCTURAL INSTRUMENTATION

PART 1 GENERAL

1.01 SECTION INCLUDES

A. Install, protect, and remove geotechnical and structural instrumentation as required herein.

B. Monitor and report data from geotechnical instrumentation.

C. Make available data interpretations to the OWNER and ENGINEER within 24 hours.

D. Provide access to each instrument location for independent data collection at times selected by the OWNER and ENGINEER.

1.02 REFERENCES

A. AASHTO: R8-96 (2019), Standard Recommended Practice for Evaluation of

Transportation-Related Earthborne Vibrations

1.03 RELATED SECTIONS

A. Section 02465 – Drilled Soldier Pile and Lagging Wall

1.04 DEFINITIONS AND DESCRIPTIONS

A. Crack Monitoring Points - Measurements of crack monitoring locations shall be identified during a pre-construction survey on the exterior faces of the adjacent walls of buildings at the Great Lakes Tissue Power Plant. The CONTRACTOR shall instrument the cracks with Avongard crack monitoring devices, or equal.

B. Vibration Monitoring - The CONTRACTOR shall perform vibration monitoring during demolition, excavation, pile installation, and backfill of the new wall next to the Great

Lakes Tissue Power Plant.

1.05 SUBMITTALS

A. Subcontractor Qualifications: Names and experience record for each Subcontractor involved with instrumentation installations.

B. Manufacturer’s product data or catalogue cuts for instruments to be installed by the subcontractor or Contractor.

C. Installation procedures and details.

D. As-built drawings for all installed instrumentation showing plan locations and elevations.

GEI Project No. 1904013 2 Section 13440

E. Calibration sheets showing data for calibrating the equipment for instrumentation.

F. Written vibration monitoring program.

G. Daily vibration monitoring reports.

1.06 QUALITY CONTROL

A. The installation of instrumentation shall be performed by a qualified subcontractor in the presence of the OWNER's representative.

B. The CONTRACTOR shall interpret instrumentation data in connection with his responsibility for construction performance, protection of adjacent facilities, and safety of workers.

PART 2 PRODUCTS

2.01 MATERIALS

A. Crack monitoring device shall be an Avongard Calibrated Crack Monitor, or approved acceptable equivalent. Devices can be obtained from Avongard Products, USA, Ltd., 2836 Osage Circle, Waukegan, IL, 60078, 708-244-4179. Epoxy putty, grout, or mechanical anchorage shall be used to fix device to the wall exterior of the buildings at

51 High Street and 225 Congress Street, in a manner acceptable to the Owner. The crack monitoring devices shall be accurate to within 1 millimeter.

B. Ground vibration monitoring shall be performed using a minimum of two seismographs to measure the peak particle velocities of the ground resulting from construction activities. Provide model SSU 1000DK as manufactured by P.R. Berger & Associates, Warrandale, PA, model Blastmate II as manufactured by Instatel, Inc. of Kanata

(Ottawa), Ontario, Canada, or model S-7-067, as manufactured by Slope Indicator Co., Seattle, WA, or acceptable equivalent. The seismograph shall have the following minimum features:

1. Seismic range: 0.005 to 10 inches per second with an accuracy of 5%.

2. Flat frequency response: 2 to 200 Hertz.

3. Three component sensor.

4. Two power sources: Internal rechargeable battery and charger and 115 volts AC.

Battery must be capable of supplying power to monitor vibrations continuously for up to 24 hours.

5. Capable of internal dynamic calibration.

6. Continuous monitoring mode must be capable of recording peak velocities.

GEI Project No. 1904013 3 Section 13440

PART 3 EXECUTION

3.01 INSTALLATION OF CRACK MONITORING POINTS

A. CONTRACTOR shall submit procedures for installation of crack monitoring points.

CONTRACTOR shall execute work according to manufacturer's recommendations.

3.02 VIBRATION MONITORING

A. Vibration monitoring equipment shall be located at adjacent structures closest to the work area with the permission of the adjacent Owner. Any accelerometers used should be secured using a sandbag.

B. The recorded vibrations must not exceed a peak particle velocity (PPV) of 0.5 in/sec.

Propose as necessary, for approval by the ENGINEER, alternate construction methods to ensure that vibrations remain below an acceptable limit. An action plan that details the acceptable limits for vibration and soil movements and resultant action plans for each type of monitoring point of instrument must follow a tiered approach as follows.

1. When vibration readings are below a peak particle velocity (PPV) of 0.5 in/sec., the CONTRACTOR and the ENGINEER will note vibrations. The

CONTRACTOR may continue all operations.

2. When vibration readings exceed a peak particle velocity (PPV) of 0.5 in/sec., the

CONTRACTOR must temporarily suspend operations. Provide the PPV and frequency data to the ENGINEER. The CONTRACTOR, the ENGINEER, and the OWNER will inspect the adjacent structures for signs of settlement or damage. The Contractor must review equipment, means and methods, and material stockpile locations for impacts to the existing structure, and make adjustments accordingly with the approval of the ENGINEER. The ENGINEER may establish new vibration limits based on inspection of the Great Lakes Tissue power plant. The CONTRACTOR cannot continue operations until instructed to do so by the ENGINEER. No compensation will be made for idle equipment, however, should this process impact the schedule, an extension of contract time may be granted equal to the amount of time required for site inspection, until the

ENGINEER instructs the CONTRACTOR to continue work.

3. When vibration readings exceed a peak particle velocity (PPV) of 0.5 in/sec., or when damage to existing structures is detected, the CONTRACTOR must cease all operations pending a review of field conditions by the OWNER and

ENGINEER. Changes to means and methods will be required. The

CONTRACTOR cannot continue operations until instructed to do so by the

ENGINEER. Compensation for delays will be evaluated by the OWNER and

ENGINEER, and should this process impact the schedule, an extension of contract time may be granted equal to the amount of time required for site inspection, until the ENGINEER instructs the CONTRACTOR to continue work.

3.03 INSTALLATION SCHEDULE

A. All instruments shall be installed prior to commencement of relevant work activities.

GEI Project No. 1904013 4 Section 13440

B. Instruments shall be tested, after completion of installation, by the CONTRACTOR's instrumentation representative with OWNER's and ENGINEER's representative present.

Instruments that are found to be inoperative shall be immediately replaced by the

CONTRACTOR.

C. CONTRACTOR shall be responsible for the protection, maintenance, and repair of instrumentation and monitoring points. Repair operations shall conform to the same requirements as initial installations.

3.04 MONITORING SCHEDULE

A. A complete set of baseline readings shall be made on all instrumentation installed prior to commencement of work activities. This baseline information or preconstruction survey shall be conducted to document the condition of each building and structure within 50 feet of the proposed wall and shall be transmitted to the OWNER and ENGINEER before work activities commence.

B. Formal initial background seismograph readings shall be measured for a continuous period of 48 hours on weekdays prior to construction. Vibration monitoring shall also be performed during the first three days of any new construction activity including demolition, excavation, dewatering, installation of sheet piling, and backfill of the new wall.

C. Crack monitoring points to be monitored daily unless otherwise specified by OWNER and ENGINEER.

3.05 REMOVAL OF INSTRUMENTS

A. Remove instruments when instructed to do so by the OWNER and ENGINEER.

B. Backfill and restore all surfaces.

END OF SECTION

A2-2000-5

ATTACHMENT 2 TO ADDENDUM NO. 2

A2-2000-6

ATTACHMENT 3 TO ADDENDUM NO. 2

This Attachment 3 to Addendum No. 2 provides all bidders with the following revised Project Manual Articles:

1. Revised Schedule of Alternates

a. Revised language for Alternate 1 to reflect Add alternate instead of Deduct alternate.

b. Included line for Contractor Option Value Engineered Alternative wall designs.

2. Revised Schedule of Change Order Prices

a. Included request for unit pricing of pile splicing and additional soldier pile depth.

STATE OF MICHIGAN (OWNER AND CONTRACTOR) BID SUMMARY

MICHSPEC DTMB 00300 − 5 (R 03/25)

6.2 Schedule of Alternates - The Bidder will complete (or deduct from the Contract) the parts of the Work designated by the Alternates that follow and accept in full payment (or allow in full credit) for those parts of the Work the following Bid Prices:

Alternate

Item No.

Bid

Quantity

Description

Unit

Price

Item Bid

Price

1 1 LSUM Barge Only Access (Add)

2 1 LSUM Contractor Defined Value Engineered Alternative (Deduct)

The Bidder further acknowledges and agrees that the separate prices bid on this “Schedule of Alternates,” where they are applicable and deemed acceptable by the Owner, will be used if incorporated into the Contract when the Owner issues the Notice of Award.

Name of the Bidder _________________________________________ File No. ___751/17264.ABG__________

Date _________________________

SIGMA VENDOR NUMBER _________________________________

Telephone No. _______________________

STATE OF MICHIGAN (OWNER AND CONTRACTOR) BID SUMMARY

MICHSPEC DTMB 00300 − 6 (R 03/25)

ARTICLE 7 SCHEDULE OF CHANGE ORDER PRICES

7.1 The Bidder shall use this “Schedule of Change Order Prices” to propose contingent prices. The proposed contingent Change Order prices set forth in this schedule, at the sole discretion of the Owner, may, or may not be incorporated into the Contract Documents. The Owner reserves the right to negotiate contingent Change Order prices set forth herein prior to their possible incorporation into the Contract Documents.

Proposed Change Order prices will not affect determination of the lowest Bid.

7.2 Subject to their incorporation into the Contract Documents, as provided in the Agreement, the Bidder will add to, or deduct from, the

Contract Work covered by the contingent prices that follow and accept in full payment, or allow in full credit, for that Work (a) those prices bid by the Bidder, or (b) if a particular price is not bid, the price proposed by the Owner (and shown in the appropriate column):

Item No. Bid

Quantity

Description

Unit

Price

Item Bid

Price

1 TBD Pile Splicing (per each)

2 TBD Additional Soldier Pile Depth (per linear foot)

Name of the Bidder _________________________________________

File No. ___751/17264.ABG______

Date _________________________

SIGMA VENDOR NUMBER _________________________________

Telephone No. _______________________

A2-2000-7

ATTACHMENT 3 TO ADDENDUM NO. 2