Attach_3_Spec_Amd00001_0001.pdf

TECHNICAL SERVICE CENTER

WRITTEN SPECIFICATIONS SIGNATURE SHEET

Specifications Title: _________________________________________________

Project Title:

Region:

Prepared:

Technical Approval:

Certified:

CONCONULLY DAM CAS

Phase II Seismic Modifications

Foundation Improvement Test Section

Okanogan Project, Washington

MICHAEL VON

BUHR

Digitally signed by MICHAEL

VON BUHR

Date: 2021.03.15 09:58:34 -06'00'

ERIC

BERGSTROM

Digitally signed by ERIC

BERGSTROM

Date: 2021.03.15 10:35:28 -06'00'

ROBERT

CARLSON

Digitally signed by

ROBERT CARLSON

Date: 2021.03.17 09:24:12 -06'00'

P.E.

P.E.

P.E.

AMD/MOD

No.

Technical Approval Signature:

Prepared By Signature:

Revised Sections:

AMD 00001 01 51 00, 31 23 11,

31 32 35, 32 92 20

Foundation Improvement Test Section Conconully Seismic Modifications Okanogan Project - Washington Amendment No. 00001

Temporary Utilities (Revised)

01 51 00 - 1

SECTION 01 51 00

TEMPORARY UTILITIES

PART 1 GENERAL

1.01 MEASUREMENT AND PAYMENT

A. Cost:

1. Include in prices offered in the Price Schedule for other items of work.

1.02 REFERENCE STANDARDS

A. Institute of Electrical and Electronics Engineers (IEEE)

1. IEEE C2-2017 National Electrical Safety Code (NESC)

1.03 TEMPORARY ELECTRICITY

A. Provide electric power required for construction.

B. Provide generators, transmission lines, distribution circuits, transformers, and other electrical equipment and facilities required for obtaining power and distributing power to points of use.

C. Comply with IEEE C2 clearances and spacing for temporary communications and supply lines.

D. Existing electric power at work site is single phase.

E. Local utility to contact for electric power is Okanogan County Public Utility District.

1.04 TEMPORARY WATER

A. Provide water required for construction purposes.

B. Water from Conconully Reservoir will be available for construction purposes.

1. No charge will be made for water obtained from this source.

2. Do not obtain water at reservoir locations designated as wetlands on the Drawings.

3. Do not obtain water from areas downstream of the dam.

C. Provide potable water for Contractor’s on-site employees.

1. Reclamation does not have a source for this water.

Temporary Utilities (Revised)

01 51 00 - 2

D. The Conconully Reservoir water has been tested and meets requirements for water used in grouting.

E. Provide means of conveying water to points of use.

1.05 TELEPHONE

A. Cellular telephone service is sporadic on the site.

B. Obtain hard wired service from local provider.

1. There are existing telephone lines to the site for instrumentation.

1.06 PORTABLE TOILET FACILITIES

A. Provide portable toilet facilities with hand washing stations for construction workers.

PART 2 PRODUCTS

Not Used

PART 3 EXECUTION

3.01 REMOVAL

A. Remove temporary equipment and facilities upon completion of work under this contract.

END OF SECTION

Earthwork (Revised)

31 23 11 - 2

1.03 SUBMITTALS

A. Submit the following in accordance with Section 01 33 00 - Submittals.

B. RSN 31 23 11-1, Excavation and Compaction Plan:

1. Describe equipment, stockpile areas, schedule, and methods for excavation.

2. Describe equipment, schedule, sequence, and methods for placement and compaction of backfill.

3. Include haul route plans for excavation, stockpile, and backfill.

1.04 PROJECT CONDITIONS

A. Results of Subsurface Investigations: Refer to Section 51 00 30 – Reservoir and Piezometer Data, Section 53 10 00 – Geologic Investigations and Section 53 20 00 – Records of Geologic and Subsurface Investigations.

B. Modifications were performed at Conconully Dam in the 1960’s. These modifications included demolition of the original dam spillway, rock excavation for construction of a replacement spillway and reconstruction of the dam crest and downstream face.

Materials removed as part of 1960’s dam modifications were wasted downstream of the dam. The waste berm materials are likely to consist of gravel, sand and silt with some boulders and cobbles. The waste berm materials are anticipated to include demolished concrete boulders with exposed rebar. The concrete boulders can be up to 12 feet long or greater.

C. The anticipated typical groundwater elevation is below the bottom of the excavation.

1. Artesian groundwater pressures are present below the ash layer shown on the drawings.

PART 2 PRODUCTS

2.01 EXCAVATED MATERIALS

A. Materials excavated in the work area for the test section to the lines and grades shown on the Drawings. The excavated materials will be used as the backfill materials at the end of test section construction.

2.02 DEEP SOIL MIXING SPOILS

A. Material consisting of mixed soil and grout that is considered waste at the surface of the deep soil mixing operation.

31 23 11 - 3

PART 3 EXECUTION

3.01 EXCAVATION, GENERAL

A. Excavate at the location of the test sections to lines and elevations shown on the drawings or as determined by the COR.

B. The Government reserves the right, during progress of work, to vary slopes, grades, and dimensions of excavations from those specified.

C. The Government does not represent that excavation performed under these specifications can be made to or maintained at paylines shown on the drawings or described in these specifications.

D. Perform excavation in the dry. Remove any water entering the excavation due to seepage or storm runoff in accordance with Section 31 03 33 – Removal of Water from Excavation.

E. Stockpile excavated materials within the areas delineated on the Drawings.

F. Stockpile concrete boulders sparate from other excavated materials.

3.02 DEEP SOIL MIX SPOIL STOCKPILE

A. Stockpile deep soil mix spoils in the stockpile areas shown on the Drawings as necessary.

1. Do not mix the spoil material with the excavated berm materials.

3.03 PLACING BACKFILL

A. Place deep soil mix spoils and excavated material within the test section excavation to the original ground surface shown on the Drawings, or as determined by the COR.

1. Place deep soil mix spoils in the backfill prior to using stockpiled excavated materials.

2. If the final surface will be above the original ground surface, grade the final surface to drain to the spillway channel.

3. Do not include excavated concrete boulders in the backfill. Leave these stockpiled materials in place at the stockpile location.

B. Place in continuous, approximately horizontal layers.

3.04 COMPACTING BACKFILL

A. Compaction Equipment:

1. Smooth steel drum roller

a. Minimum drum width: 6 feet

31 23 11 - 4

b. Minimum operating weight: 35,000 lbs

B. Compaction:

1. Compact in horizontal layers to compacted thickness of 18 inches or less.

2. Keep backfill moist during compaction. Add water as necessary or as determined by COR.

3. Compact each lift with 4 passes of the required roller.

a. One pass is defined as one full travel of the roller across the backfill material layer in one direction.

4. Do not operate roller at speeds exceeding 1.5 miles per hour.

5. Do not use vibration during compaction.

3.05 PROTECTION

A. Protect excavated and spoil material from erosion, excessive saturation, freezing, and surface drainage following excavation and until the end of backfill operations.

END OF SECTION

Deep Soil Mixing (Revised)

31 32 35 - 3

1.04 PROJECT CONDITIONS

A. Results of Subsurface Investigations: Refer to Section 53 10 00 – Geologic Investigations and Section 53 20 00 – Records of Geologic and Subsurface Investigations.

B. Modifications were performed at Conconully Dam in the 1960’s. These modifications included rock excavation for the spillway and reconstruction of the dam crest and downstream material. Material removed as part of the 1960’s dam modifications were wasted downstream of the dam (Emsg-toe berm). The Emsg-toe berm materials are likely to consist of gravel, sand, and silt with some cobbles. The waste berm materials are anticipated to include demolished concrete boulders with exposed rebar. The concrete boulders can be up to 12 feet long or greater.

C. Construction of the DSM test sections consists of constructing DSM columns through part of the Emsg toe berm into foundation materials described in the geologic investigations.

D. The purpose of constructing the DSM test section columns is to provide information on the mix design, grout injection rates, withdrawal rates, rotation speed, constructability, strength, and related construction quantities such as percentage of spoil for use in future project designs.

E. Soft ground conditions may be encountered within the test section excavation limits. The foundation soils may not provide adequate bearing capacity for equipment travel. A working platform may be necessary to provide adequate bearing capacity.

F. The access road from the crest of the dam to the toe of the dam (Work area) is approximately 12 feet wide. Access road improvements may be necessary for essential equipment (the Contractor shall keep as much equipment in the Contractor use area as feasible).

G. Deep soil mixed columns shall be constructed using the wet mixing method.

H. Compressed air shall not be allowed for use in construction of the deep soil mixed columns.

1.05 SUBMITTALS

A. Submit in accordance with Section 01 33 00 - Submittals.

B. RSN 31 32 35-1, Deep Soil Mixing Personnel Experience:

1. Qualifying experience of individual responsible for supervising field execution of the deep soil mixing test sections.

2. Qualifying experience of individual responsible for preparing and evaluating key parameters of the test section design such as the mix design, grout injection rate, mixing tool withdrawal rate, mixing tool rotation speed, single-axis versus

Deep Soil Mixing (Revised)

31 32 35 - 11

b. Disturbance to the area downstream of the access road must stay a minimum of 50 feet away from the wetlands area designated on the Drawings.

c. Protect all piezometers, seepage monitoring weirs, and other access roads located downstream of the dam face access road.

2. Material for access road improvements may be obtained from required test section excavation or from the Contractor Use area.

3. Prior to improvements, remove any vegetation from the area to be disturbed in accordance with Section 31 11 00 – Clearing.

4. Following construction, seed the slope below the access road in accordance with Section 32 92 20 – Seeding.

5. See drawings for Access Road locations.

3.03 WORKING PLATFORM

A. The Contractor shall assess the need for a working platform following excavation to the required depths for test section construction.

1. If the foundation materials are insufficient to support the construction equipment, design and construct a working platform.

2. The working platform materials will stay in place at the end of construction.

3.04 EQUIPMENT

A. Grout Plant:

1. Water Tank:

a. Sufficient to adequately supply water to mixer to provide required pumping rate.

2. Mixers: High-speed colloidal-type.

a. Fitted with adequate measuring devices, such as water meters and balances, to ensure that materials are being mixed in the correct proportions.

1) Meters and balances:

a) Control delivery of material and water so inaccuracies in feeding and measuring shall not exceed 1 percent.

b) Provide totalizer(s) and a water meter mounted on the plant, readily accessible by COR.

c) Use range of scale suitable for the batching equipment supplied.

d) Demonstrate testing and calibration procedures to COR who will approve the procedures before beginning deep soil mixing.

Seeding (Revised)

32 92 20 - 4

2.06 STRAW WATTLES

A. Cylinders of plant material such as weed-free straw, coir, wood chips, excelsior, or wood fiber encased in netting made with natural plant fibers unaltered by synthetic materials.

1. Minimum 8-inches in diameter.

2.07 POSTS

A. Wooden posts: 1 ½ inches by 1 ½ inches by 4 feet minimum dimensions, pointed on end driven into the ground.

PART 3 EXECUTION

3.01 SITE PREPARATION/HERBICIDE APPLICATION

A. Install temporary cattle barrier to prevent cattle entry to Contractor use or Work areas.

B. Utilize weed wash stations for equipment entering and leaving the Work area.

C. Treat the Work area with herbicide.

1. Include the knapweed infestation in the Work area.

2. Follow Manufacturer’s recommendations for broadcast application rate (7 fl oz per acre for Milestone).

3.02 SEEDBED PREPARATION

A. Complete prior to seeding, and mulching or hydromulching.

B. Scarify or harrow and rake topsoil to minimum depth of three inches.

C. Remove stiff clods, lumps, roots, litter, stones, and other foreign material greater than 6 inches in size from the surface. Place removed materials in the smallest area possible in a corner of the Contractor Use area.

D. Fill or smooth topsoil surface to remove rills, gullies and depressions.

E. Protect prepared topsoil surfaces from erosion and washouts. Repair damaged surfaces as required.

3.03 SEEDING

A. Deleted