Sitkoh_river_specs_bg_2011_0210.doc

Table of Contents

1Table of Contents

Preface 101 - Terms, Format, and Definitions

101.01 Meaning of Terms.

101.03 Abbreviations.

101.04 Definitions.

102 - Bid, Award, and Execution of Contract 102 Bid, Award, and Execution of Contract 103 - Scope of Work Deletions 104 - Control of Work Deletions

104.06 Use of Roads by Contractor

105 - Control of Material

105.02 Material Sources.

105.02(a) Government-provided sources.

105.05 Use of Material Found in the Work.

106 - Acceptance of Work

106.01 Conformity with Contract Requirements.

106.07 Delete

107 - Legal Relations and Responsibility to the Public

107.05 Responsibility for Damage Claims.

107.06 Contractor’s Responsibility for Work.

107.09 Legal Relationship of the Parties.

107.10 Environmental Protection.

108 - Prosecution and Progress 108 Delete.

109 - Measurement and Payment 109 Deletions

109.02 Measurement Terms and Definitions.

109.02 Measurement Terms and Definitions.

151 - Mobilization

151.01 Description

155 - Schedules for Construction Contracts 155 Delete.

157 – Soil Erosion Control

157.03 General

201 - Clearing and Grubbing

201.05 (b) 584 - Log Structures Description Materials Construction

584.06 General.

584.07 Performance.

Measurement

584.08 Method.

Payment 594.09 622—Rental Equipment

622.02 Rental Equipment.

622.04 Method.

648—Stream Simulation Material

648.02 Conform to the following Section and Subsections:

Bed Class Construction

648.03 General.

648.04 Equipment Operations.

648.05 Equipment Limitations.

648.06 Excavation.

648.07 Dewatering.

648.08. Rewatering.

648.09 Blasting and Rock Removal

648.10 Placed Stream Simulation Bed Material.

648.11 Rock Bedforms (steps, weirs, riffles, pools), Forcing Features, and Bank Construction.

648.12 Log and Root Wad Structures.

Measurement

648.13 Method.

Payment

Preface

Preface_wo_03_15_2004_m Delete all but the first paragraph and add the following:

The Forest Service, US Department of Agriculture has adopted FP-03 for construction of National Forest System Roads.

101 - Terms, Format, and Definitions

101.00_nat_us_07_25_2005

101.01_nat_us_02_17_2005

101.01 Meaning of Terms.

Add the following:

Delete all references in FP-03 to Transportation Acquisition Regulations (TAR).

101.03_nat_us_06_16_2006

101.03 Abbreviations.

Add the following to (a) Acronyms:

AFPA

MSHA

NIST

NESC

WCLIB

American Forest and Paper Association Mine Safety and Health Administration National Institute of Standards and Technology National Electrical Safety Code West Coast Lumber Inspection Bureau

Add the following to (b) SI symbols:

101.04_nat_us_06_16_2006

101.04 Definitions.

Delete the following definitions and substitute the following:

Bid Schedule--The Schedule of Items.

Bridge--No definition.

Contractor--The individual or legal entity contracting with the Government for performance of prescribed work. In a timber sale contract, the contractor is the “purchaser”.

Culvert--No definition.

Right-of-Way--A general term denoting (1) the privilege to pass over land in some particular line (including easement, lease, permit, or license to occupy, use, or traverse public or private lands), or (2) Real property necessary for the project, including roadway, buffer areas, access, and drainage areas.

Add the following:

Adjustment in Contract Price--“Equitable adjustment,” as used in the Federal Acquisition Regulations, or “construction cost adjustment,” as used in the Timber Sale Contract, as applicable.

Change--“Change” means “change order” as used in the Federal Acquisition Regulations, or “design change” as used in the Timber Sale Contract.

Design Quantity--“Design quantity” is a Forest Service method of measurement from the FS-96 Forest Service Specifications for the Construction of Roads and Bridges. Under these FP specifications this term is replaced by the term “Contract Quantities”.

Forest Service--The United States of America, acting through the Forest Service, U.S. Department of Agriculture.

Neat Line--A line defining the proposed or specified limits of an excavation or structure.

Pioneer Road--Temporary construction access built along the route of the project.

Purchaser--The individual, partnership, joint venture, or corporation contracting with the Government under the terms of a Timber Sale Contract and acting independently or through agents, employees, or subcontractors.

Protected Streamcourse--A drainage shown on the plans or timber sale area map that requires designated mitigation measures.

Road Order--An order affecting and controlling traffic on roads under Forest Service jurisdiction. Road Orders are issued by a designated Forest Officer under the authorities of 36 CFR, part 260.

Schedule of Items--A schedule in the contract that contains a listing and description of construction items, quantities, units of measure, unit price, and amount.

Utilization Standards--The minimum size and percent soundness of trees described in the specifications to determine merchantable timber.

Add Figure 101-1—Illustration of road structure terms:

Figure 101-1—Illustration of road structure terms.

102 - Bid, Award, and Execution of Contract

102.00_nat_us_02_16_2005

102 Bid, Award, and Execution of Contract

Delete Section 102 in its entirety.

103 - Scope of Work

103.00_nat_us_02_16_2005

Deletions

Delete all but subsection 103.01 Intent of Contract.

104 - Control of Work

104.00_nat_us_06_16_2006

Deletions

Delete Sections 104.01, 104.02, and 104.04.

104.06_nat_us_02_17_2005

Add the following subsection:

104.06 Use of Roads by Contractor

The Contractor is authorized to use roads under the jurisdiction of the Forest Service for all activities necessary to complete this contract, subject to the limitations and authorizations designated in the Road Order(s) or described in the contract, when such use will not damage the roads or national forest resources, and when traffic can be accommodated safely.

105 - Control of Material

105.02_nat_us_01_18_2007

105.02 Material Sources.

105.02(a) Government-provided sources.

Add the following:

Comply with the requirements of 30 CFR 56, subparts B and H. Use all suitable material for aggregate regardless of size unless otherwise designated. When required, re-establish vegetation in disturbed areas according to section 625.

105.05_nat_us_05_12_2004

105.05 Use of Material Found in the Work.

Delete 105.05 (a) and (b) and the last sentence of the second paragraph and substitute the following:

Materials produced or processed from Government lands in excess of the quantities required for performance of this contract are the property of the Government. The Government is not obligated to make reimbursement for the cost of producing these materials.

106 - Acceptance of Work

106.01_nat_us_03_29_2005

106.01 Conformity with Contract Requirements.

Delete Subsection 106.01 and substitute the following:

Follow the requirements of FAR Clause 52.246-12 Inspection of Construction.

References to standard test methods of AASHTO, ASTM, GSA, and other recognized standard authorities refer to the methods in effect on the date of solicitation for bids.

Perform all work to the lines, grades, cross-sections, dimensions, and processes or material requirements shown on the plans or specified in the contract.

Incorporate manufactured materials into the work according to the manufacturer’s recommendations or to these specifications, whichever is more strict.

Plan dimensions and contract specification values are the values to be strived for and complied with as the design values from which any deviations are allowed. Perform work and provide material that is uniform in character and reasonably close to the prescribed value or within the specified tolerance range. The purpose of a tolerance range is to accommodate occasional minor variations from the median zone that are unavoidable for practical reasons.

When standard manufactured items are specified (such as fence, wire, plates, rolled shapes, pipe conduits, etc., that are identified by gauge, unit mass, section dimensions, etc.), the identification will be considered to be nominal masses or dimensions. Unless specific contract tolerances are noted, established manufacturing tolerances will be accepted.

The Government may inspect, sample, or test all work at any time before final acceptance of the project. When the Government tests work, copies of test reports are furnished to the Contractor upon request. Government tests may or may not be performed at the work site. If Contractor testing and inspection is verified by the Government, the Contractor’s results may be used by the Government to evaluate work for acceptance. Do not rely on the availability of Government test results for process control.

Acceptable work conforming to the contract will be paid for at the contract unit bid price. Four methods of determining conformity and accepting work are described in Subsections 106.02 to 106.05 inclusive. The primary method of acceptance is specified in each Section of work. However, work may be rejected at any time it is found by any of the methods not to comply with the contract.

Remove and replace work that does not conform to the contract, or to prevailing industry standards where no specific contract requirements are noted, at no cost to the Government.

(a) Disputing Government test results. If the accuracy of Government test results is disputed, promptly inform the CO. If the dispute is unresolved after reasonable steps are taken to resolve the dispute, further evaluation may be obtained by written request. Include a narrative describing the dispute and a proposed resolution protocol that addresses the following:

(1) Sampling method;

(2) Number of samples;

(3) Sample transport;

(4) Test procedures;

(5) Testing laboratories;

(6) Reporting;

(7) Estimated time and costs; and

(8) Validation process.

If the evaluation requires additional sampling or testing be performed, mutually agree with the Government on witnessing procedures and on sampling and testing by a third party laboratory. Use a third party laboratory accredited by the AASHTO accreditation program. Provide proof of the laboratory’s accreditation for the test procedures to be used. Do not use the same laboratory that produced the disputed Government test results or that produced the test results used as a basis for the dispute.

The CO will review the proposed resolution protocol and may modify it before final approval and execution.

The Government will use the approved resolution protocol test results to determine the validity of the disputed testing. If the Government test results are validated, the Contractor will be responsible for all costs associated with developing and performing the resolution protocol. If the Government test results are not validated, the Government will be responsible for all costs associated with developing and performing the resolution protocol. If the validity of the Government test results cannot be determined, the Contractor and Government will equally share all costs associated with developing and carrying out the resolution protocol.

(b) Alternatives to removing and replacing non-conforming work. As an alternative to removal and replacement, the Contractor may submit a written request to:

(1) Have the work accepted at a reduced price; or

(2) Be given permission to perform corrective measures to bring the work into conformity.

The request must contain supporting rationale and documentation. Include references or data justifying the proposal based on an evaluation of test results, effect on service life, value of material or work, quality, aesthetics, and other tangible engineering basis. The CO will determine disposition of the nonconforming work.

106.07_nat_us_05_11_2004

106.07 Delete

Delete subsection 106.07.

107 - Legal Relations and Responsibility to the Public

107.05_nat_us_05_11_2004

107.05 Responsibility for Damage Claims.

Delete the entire subsection.

107.06_nat_us_06_16_2006

107.06 Contractor’s Responsibility for Work.

Delete the following from the first paragraph.

“except as provided in Subsection 106.07”.

107.09_nat_us_06_16_2006

107.09 Legal Relationship of the Parties.

Delete the entire subsection.

107.10_nat_us_06_16_2006

107.10 Environmental Protection.

Add the following:

Design and locate equipment repair shops, stationary refueling sites, or other facilities to minimize the potential and impacts of hazardous material spills on Government land.

Before beginning any work, submit a Hazardous Spill Plan. List actions to be taken in the event of a spill. Incorporate preventive measures to be taken, such as the location of mobile refueling facilities, storage and handling of hazardous materials, and similar information. Immediately notify the CO of all hazardous material spills. Provide a written narrative report form no later than 24 hours after the initial report and include the following:

· Description of the item spilled (including identity, quantity, manifest number, and other identifying information).

· Whether amount spilled is EPA or state reportable, and if so whether it was reported, and to whom.

· Exact time and location of spill including a description of the area involved.

· Containment procedures.

· Summary of any communications the Contractor had with news media, Federal, state and local regulatory agencies and officials, or Forest Service officials.

· Description of clean-up procedures employed or to be employed at the site including final disposition and disposal location of spill residue.

When available provide copies of all spill related clean up and closure documentation and correspondence from regulatory agencies.

The Contractor is solely responsible for all spills or leaks that occur during the performance of this contract. Clean up spills or leaks to the satisfaction of the CO and in a manner that complies with Federal, state, and local laws and regulations.

107.10_05_us_07_27_2005

108 - Prosecution and Progress

108.00_nat_us_02_16_2005

108 Delete.

Delete Section 108 in its entirety.

109 - Measurement and Payment

109.00_nat_us_02_17_2005

109 Deletions

Delete the following entire subsections:

109.06 Pricing of Adjustments.

109.07 Eliminated Work.

109.08 Progress Payments.

109.09 Final Payment.

109.02_nat_us_06_16_2006

109.02 Measurement Terms and Definitions.

(b) Contract quantity.

Add the following:

Contract quantities will be adjusted only when there are errors in the original design of 15% or more.

Change the following:

“(b) Cubic yard” to “(c) Cubic yard”.

Add the following definition:

(p) Thousand Board Feet (Mbf). 1,000 board feet based on nominal widths, thickness, and extreme usable length of each piece of lumber or timber actually incorporated in the job. For glued laminated timber, 1,000 board feet based on actual width, thickness, and length of each piece actually incorporated in the job.

109.02_0114_us_05_16_2005

109.02 Measurement Terms and Definitions.

Add the following definition:

(q) Actual quantity. (AQ) These quantities are determined from measurements of completed work.

151 - Mobilization

151.01_0105_us_02_23_2005

151.01 Description

Add the following at the end of the last sentence:

“Work also includes cleaning of all equipment used at the project site. Clean all construction equipment prior to entry on the project site. Remove all dirt, plant parts and material that may carry noxious weed seeds into the area. Only construction equipment inspected by the Forest Service will be allowed to operate within the project area. Treat subsequent move-ins of equipment the same as the initial move-in. Clean truck beds and dump boxes hauling to the project site prior to entering the work area.”

155 - Schedules for Construction Contracts

155.00_nat_us_05_11_2004

155 Delete.

Delete Section 155 in its entirety.

157 – Soil Erosion Control

157.03_bg_02_10_2011

157.03 General

Add the following after the first paragraph:

For all projects involving bridges and culvert construction or channel reconstruction submit an erosion control plan concurrently with dewatering plans unless directed by the CO. For equipment rental projects no erosion control plan is required by the contractor.

201 - Clearing and Grubbing

201.05_10_us_07_14_2006

201.05_10_bg_02_24_2008

201.05 (b) Delete entire paragraph and replace with the following:

Grub all embankment areas. Undisturbed stumps may be left in place if they protrude less than 6 inches above the original ground and will be covered with more than 2 feet of embankment.

For temporary access that will be decommissioned or stored on stream restoration projects, Grub all embankment areas. Undisturbed stumps may be left in place if they protrude less than 6 inches above the original ground and will be covered with more than 1 feet of embankment.

584 - Log Structures 584_all_bg_02_10_2011 The following section is added:

Description

584.01 This work consists of collecting, transporting, furnishing, fabricating, and installing log and timber structures, and all associated hardware and other required materials for constructing log culverts, log crib bulkheads, abutments, piers, dams, instream structures, diversion structures, berm logs, and logjams when specified in the contract.

Materials

584.02 Requirements. Furnish materials that conform to specifications in the following section and subsections:

Structural Concrete

Reinforcing Steel

Timber Structures

Log Crib Backfill ............................................................... 704.12

Wire Rope .......................................................................... 709.02

Geotextiles ......................................................................... 714.01

584.03 Logs. Furnish logs used for culverts, bulkheads, abutments, cribs, piers, or berm logs within the dimensional tolerances and of the species shown on the plans. They must be of high quality, straight, sound, and free of wind shake, decay, or excessive twist (spiral grain with a slope of grain relative to the longitudinal axis of the log exceeding 1 in 8). Ensure that knots in the middle half of the stringer length do not significantly affect structural capacity. If, after cutting, trees are found to be defective notify the CO.

Logs / trees for instream structures, logjams, and diversions will leave rootwads attached to log. Log/ trees and rootwad lengths will be AS SHOWN ON THE DRAWINGS, or as designated in the field by the CO or their designee.

Obtain written approval from the CO or their designee for all logs to be used in the structure.

584.04 Timber & Lumber. Furnish structural lumber and timber in accordance with the species, grades, and dimensions shown on the plans and in accordance with Section 557.

Logs for instream structures, logjams, and diversions will be designated in the field by the CO.

584.05 Aggregate. When required, furnish aggregate for decking or surfacing to meet the requirements shown on the plans.

Construction

584.06 General. Perform excavation, foundation, backfill, and embankment work specified in Sections 204 and 209, as applicable.

Handle all logs and timber carefully to prevent damage to the wood and/or preservative treatment.

Dispose of all debris resulting from operations in accordance with Section 203 and as approved by the CO or their designee.

Construct log crib abutments, piers, and/or bulkheads as shown on the plans. Anchor tie backs for log crib to the face logs by notching or by lashing.

584.07 Performance. Construct log crib bulkheads, abutments, piers, instream structures, logjams, and diversions as shown on the plans, with attention paid to the details of erection, fit-up, and connection. Obtain written approval for all deviations from the CO.

Place timber caps to obtain even and uniform bearing over the tops of supporting posts or piles and with post and pile ends in true alignment. Secure all caps as shown on the plans.

Match stringers for size at the bearings or connection points and place them in position so that the crown is up. Ensure that all logs within a single tier are approximately the same diameter. Alternate tiers of logs butt to tip as necessary to maintain the vertical dimensions shown on the plans. Locate any knots that may affect the strength of the member in the top portion of the member. Cut members to length with a square cut.

Cut or hew the bottom surface of the crib base logs only to the depth necessary to achieve the required bearing area. Block or shim tip ends that are smaller than the largest tip. Cut or dap butt ends to the depth of the largest top end. Allow the maximum slope of any dap to be 1 to 10. Make top and bottom cuts parallel. Require shims or blocks used under small ends to cover the entire bearing area.

Notch log crib bulkhead logs at the connection points specified in the contract, and lash all connections with staples and wire rope of the diameter shown on the plans. Use a minimum of 4 staples per wrap of cable in lashings. Maximum depth of notches shall be as shown on the plans but not to exceed 1/4 the diameter of the log being notched, unless approved otherwise by the CO. Select diameters and notching depths to ensure that the final elevation of the top log of the bulkhead is within +/- 3 inches of the elevation shown on the plans. Orient daps or notches at connections with the dap or notch facing down. Place wood chinking and geotextile for backing behind open spacing between logs so that no material can escape or be washed out. Place material meeting the gradation requirements of Section 704.12 inside and around log bulkheads and abutment structures. Backfill log crib bulkheads in accordance with Section 208 and Subsection 204.11 (a).

Use tiebacks or other abutment anchoring devices as shown on the plans or as approved in writing by the CO.

Lash and install berm logs in accordance with the details shown on the plans. Place backfill around berms to prevent seepage of water through the berm.

Measurement

584.08 Method. Measure the Section 584 items listed in bid schedule according to Subsection 109.02 and the following as applicable.

Measure log crib bulkheads, abutments, and piers on a lump sum each basis, including all work necessary to furnish, prepare, and install the log portions of the structures. . Measure structure excavation and backfill for log bulkheads, abutments, and piers in accordance with Section 209. Measure log berms by the lineal foot of installed berms.

Measure log bridges, logjams on a lump sum basis, including all work necessary to furnish, prepare, and install the log portions of the bridge superstructure, substructure and logjam units.

Measure log instream structures on a each basis, including all work materials, labor and equipment necessary to furnish, prepare, and install the log instream structures.

All unused hardware not incorporated within the project remain the property of the Government

Payment

594.09 The accepted quantities, measured as provided in Subsection 109.02 and above, will be paid at the contract price per unit of measurement for the Section 584 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05.

When log structures are not designated in the SCHEDULE OF ITEMS, they will be considered incidental to other items.

622—Rental Equipment 584_all_bg_02_24_2008

622.02 Rental Equipment.

The following is added:

The CO will designate location of work for the Contractor. The Contractor will construct the work items AS SHOWN ON THE DRAWINGS, or as required by the CO or their designee at the site.

The CO will designate native materials (logs, trees, rootwads, etc) to be used on the work site. The Contractor will excavate, cut, transport, move, clear, place, construct and operate in a safe manner consistent with OSHA regulations.

622.04 Method.

Delete the 3rd paragraph and replace with the following:

Do not measure standby time, or time for moving equipment to or from the project or between project worksites. All preventative maintenance, lubrication and fueling of equipment will be done outside of work hours. Do not measure non-operable equipment or equipment dependent upon another piece of non-operable equipment.

648—Stream Simulation

584_all_bg_02_24_2008

Replace Section 648 in its entirety with the following:

Description

648.01 This work consists of furnishing and installing rock, logs, trees, rootwads and specified fill to simulate natural stream profile, grade control structures, and streambed through culverts, bridge structures, and in existing stream channels. Work includes developing materials; hauling materials; dewatering; sediment control; placing bedding and backfill to construct stream simulation channels inside and outside of the structures (culverts, bridges, existing channels); placing, keying, and compacting designed streambed fill; constructing instream structures (steps, pools, riffles, weirs, vanes, banks); reconstructing existing channels; and all other work to complete the project.

Material

648.02 Conform to the following Section and Subsections:

Soil Erosion Control

Earthwork Geotextiles

Riprap

Special Rock Embankments and Rock Buttresses

Timber Structures

Log Bridges

Furnish fish rest stop rocks, weir rocks, and stream simulation streambed mix with the following sizes and gradations as required in the contract.

Table 648 -1

Gradation requirement for fish rest stop rock (FRS) and weir rocks

Table 648-2

Gradation requirements for streambed simulation rock, inch

Provide native log materials that are green, sound, and free of checks or defects that would affect structural integrity or accelerate decay.

Provide planking for weirs and instream structures that is sound and free of checking. Plane and seal joining surfaces to form a watertight seal when used to construct internal log or plank weirs.

Sort material for streambed simulation rock by screening (power screen or grizzly/stationary screen) and place into size class piles for inspection before mixing. Large particles can be machine sorted by heavy equipment or hand labor. Request written approval of piles before mixing by the CO or their designee. Mix stream simulation rock in proportions based on Table 638-2.

Provide bed, bank, and weir rock that is durable and at least as angular as those found in the bed. Do not use rounded gravels in culverts > 2.5% gradient except as a minor fraction of the gradation (<10%). Provide weir rock that is angular to sub-angular and has at least as many fractured faces as those found in the stream. Do not use rounded rocks in the construction of weirs within the culvert. Some rounded rocks may be used to construct weirs outside the culvert if approved by the CO in the field.

Request approval of rock to be used for weirs, banks and rock bands.

Construction

648.03 General. Place stream simulation rock on a prepared surface to form a well-graded, low permeability mass, similar in appearance and texture to the natural streambed or as required in the contract.

648.04 Equipment Operations. Maintain equipment utilized in and around streams in a clean and orderly fashion. Immediately repair any fluid or fuel leaks. To the greatest extent possible, remove all contaminated material from the site and dispose of in accordance with all State and Federal laws.

An oil spill containment kit is required on each job site when working in and around the stream. Composition of the kit is dependent on the job; determine contents of the kit as needed for each job. At a minimum, include tarps and oil-absorbent pads. Provide boom material for instream operations associated with ponds, lakes and intertidal areas and when required in the contract.

648.05 Equipment Limitations. Base equipment selection on the minimum size necessary to perform the work and minimize the impacts to the adjacent banks and streambed. Specific equipment limitations are listed in the contract. Submit a list of equipment anticipated to be used for the job at the prework meeting.

Do not drive metal track or rubber tired equipment directly on metal or concrete structure surfaces. Place a layer of stream bed mix material on the structure bottom before operating metal track or rubber tired equipment directly on metal or concrete structure surfaces.

648.06 Excavation. Excavate according to Subsection 208.04 (bridges and bottomless structure footings), and 209.04 (culverts). Control excavated material to minimize disturbance to the adjacent channel and banks. Incorporate suitable streambed materials into the project if required gradations are according to the contract.

Specific culvert installation time restrictions and installation plan requirements are indicated in the contract.

648.07 Dewatering. Dewatering or diversions are required for stream simulation culvert construction and adjacent instream work in addition to complete reconstruction of the channel. Dewatering is not required when constructing isolated or infrequent structures such as single rock or log weirs and other instream structures (rock or log vanes) in channel reconstruction areas outside 25 feet from the inlet or outlet of the culvert. Cater methods of dewatering to the site depending on flow, ground water depths at the time of installation, terrain configuration, and culvert embedment depths. Submit a dewatering plan 14 days in advance of construction. Include in the plan the method (bypass or pumping), number of pumps and capacity required, pump and bypass culvert calculations, location/layout of dewatering operations and equipment, and erosion control measures for dealing with the return flow back to the existing stream channel. The plan will be approved by the CO within 5 working days of plan submission.

Dewatering operations will be capable of passing 75% of the Q2 (2 year ) discharge or other design flows listed in the contract.

Maintain the dewatering pumping operations to ensure return flow does not exceed State of Alaska water quality standards. Water pumped from the construction site may require additional filtration by filter fabrics or other methods (settling basins, hay bales, etc) to prevent turbid water from directly entering the stream.

Place additional measures or cease operations until the discharge reaches allowable levels when turbidity exceeds State of Alaska water quality standards.

Relocate fish contained within the cofferdams before the site is completely dewatered. Place relocated fish in the closest pool upstream of the construction zone.

If trash pumps are used during construction the intake must be operated and maintained to prevent fish entrapment, entrainment, or injury with the use of perforated or slotted plate and woven wire with a mesh size not greater than 3/32 inch or a profile bar and wedgewire with openings not greater than 1/16 inch. Approach velocities shall not exceed a passive velocity of 0.2 feet per second (fps) or an active velocity 0.4 fps.

648.08. Rewatering. Conduct rewatering activities to minimize sediment movement downstream of the site upon completion of instream work. Slowly wet the site and rewater thru a sediment detention device (hay bales, silt fence, sediment retention pond) in areas within close proximity to spawning gravel or during low stream flow conditions. After the initial sediment pulse is removed, slowly breach the coffer/diversion dams to avoid a large pulse of water being sent thru the newly constructed channel.

648.09 Blasting and Rock Removal. Remove bedrock encountered during excavation to the lines and grades required in the contract. Remove rock by either mechanical means with hydraulic impact hammers / rock breakers or by ripping or blasting. When explosives are used, do not cause mortality to juvenile fish by transmitting excessive blasting overpressures through the ground to the fish habitat. Limit blasting overpressures to a maximum of 2 psi in fish habitat. If this condition is exceeded, suspend all blasting activities and immediately notify the State of Alaska Department of Natural Resources Habitat Division.

648.10 Placed Stream Simulation Bed Material. Begin construction from the downstream end working upstream, changes to construction flow will be allowed on a case by case basis due to poor stream to culvert alignment, traffic requirements, limited access, and preservation of existing trees reinforcing the banks. Deviation from construction flow (downstream to upstream) must be requested in writing and approved by the CO or their designee, 5 days in advance of construction.

Place stream simulation rock in one or more layers with a layer depth less than 1 ½ times the maximum dimension of the stream simulation rock, but no greater than 2ft. Place stream simulation rock by methods that do not cause segregation or damage to the prepared surface. Place or rearrange individual rocks to obtain a uniformly dense, compact, low permeability mass, matching stream simulation bed details. Fill voids by machine or hand tamping before placing the next lift. Compact bed materials by mechanical means such as plate compactors, loaders, etc.

Fill all voids left during placement of Stream Bed Simulation Rock, Fish Rest Stops (habitat rocks), weirs, banks and stream bed materials adjacent to footings, concrete structures or corrugated pipes with foundation fill. Use water pressure, metal tamping rods, and similar hand operated equipment to force material into all surfaces and subsurface voids between the structure and rocks, and between individual rocks.

Notify the CO at least 48 hours in advance of the stream bed material installation.

648.11 Rock Bedforms (steps, weirs, riffles, pools), Forcing Features, and Bank Construction. Construct bedforms and banks as required in the contract. Construction will proceed from downstream to upstream. Machine or hand place weirs and rock bands and key in place with select key pieces of the required size class, along with smaller materials of varying sizes to fill voids. Construct low flow channel through the center approximately 25% of the bedwidth as directed by the CO. Place weirs and rock bands so the tops are uneven, containing several high and low points to concentrate water during low flows. Place rock weir and rock band surfaces so they are higher at the outside edge of the culvert (culvert wall) and slope down to the outside edge of the constructed low flow channel of the weir at 5(H):1(V).

Construct steps with footer rocks placed before the top weir rocks are installed. Use footer rocks which are the same size class as the top weir rocks. Fill all voids with smaller materials as construction progresses to minimize permeability.

Construct banks out of large blocky key pieces (D100 ) of the required size class. Key and lock smaller materials of varying sizes to fill voids. Bank materials will be hand keyed in place and compacted depending on the size of materials used as designated in the field by the CO. Construct bank faces to be uneven, protrude into the channel, and be rough in appearance. Construct the top of the bank to be fairly uniform. Tie back constructed banks and margins at the edge of the structure walls into the existing stream banks at dimensions similar to those found in the field or as required in the contract.

When single rocks are used as forcing features and fish rest stops, bury to 50% of the diameter. Fill and compact voids around these structures. When constructed as clusters of particles, key pieces within the cluster will be buried 50% of the diameter.

Place a layer of wet straw and fine silty sand mixture within 6” of the upstream face of the weirs and ½ the distance between the weirs. Place this mixture full depth of the embedment to reduce permeability.

Notify the CO at least 48 hours in advance of the installation of any stream bed, bedform, forcing feature, log structure, or bank construction

All bank and weir rock will be approved by the CO.

648.12 Log and Root Wad Structures. Locate and place log structures as required in the contract, and/or designated in the field by the CO.

Construct log weirs with cross slope gradients not less than 5(H):1(V), unless SHOWN ON THE DRAWINGS or staked in the field by the CO, and maximum tolerance of 6(H):1(V), unless approved in writing by the CO.

Embed log weirs to a minimum depth of 6 feet beyond bank full widths or half bankfull width on each side, which ever is greater. When placing habitat logs (overhanging a portion of the stream) that lay on the banks, ensure 2/3 of the log remain behind bankful width on top of the bank.

Embed rootwad revetment trunks a minimum of 10 feet behind bankfull width limits. Bury the root to a point where the base of the bol is resting in the bottom of the bank or as required in the contract, and/or designated in the field by the CO.

Construct wood weirs as SHOWN ON THE DRAWINGS.

Measurement

648.13 Method. Measure the Section 648 items listed in the bid schedule according to Subsection 109.02 and the following as applicable.

Channel construction per linear unit includes furnishing and installing all rock and work associated with channel bed construction and includes the installation of rock weirs, pools, banks, fish rest stops, vanes and miscellaneous rock structures.

Do not measure construction of rock weirs inside of culverts, they are considered incidental to 648(03).

All log structures and rootwad revetment will be measured separately for payment if designated on the schedule of items.

Instream structures composed of rock and wood will be measured separately for payment if designated on the schedule of items.

Do not measure dewatering and diversions, they are considered incidental to construction of the structures unless measured separately for payment if designated on the schedule of items.

Work and materials required for stream simulation are considered incidental to installation of the structure unless designated on the schedule of items.

Payment

648.14 Basis. The accepted quantities will be paid at the contract price per unit of measurement for the Section 648 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05.