Alpine.Tunnel.Stabilization_contract_specs.pdf

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DIVISION 1 - GENERAL REQUIREMENTS

Section 01010 Summary of Work

Section 010250 Measurement and Payment

Section 016000 Use of Government Facilities, Utilities, Etc.

Section 0l7l00 Clean Up And Disposal

DIVISION 2 -

Section 022140 Aggregate and Pathways

DIVISION 4 - MASONRY

Section 040513 Restoration Mortaring

Section 044300 Stone Masonry

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DIVISION 1 - GENERAL REQUIREMENTS

SECTION 0l0l0 - SUMMARY OF THE WORK

PART 1 - GENERAL

1.01 LOCATION

The project is located in eastern Gunnison County, northeast of the town of Pitkin. It is accessible by narrow graded dirt road. It is located at 11,600 feet in elevation. Bidders should not expect to access this site after October 15 or before June 15 most years.

To reach the site, drive east on US Highway 50 from Gunnison to Parlin. Turn northeast onto

County Road and go to Pitkin. Continue three miles past Pitkin on FR 765 to the tunnel turn-off, FR Road 839, and turn right (east). Drive appr. 10 miles on this narrow dirt road to the site.

The site is accessible by regular two-wheel drive. Upon reaching the Tunnel parking area, walk past the gate to the wood frame Telegraph Office. Both masonry ruins are located directly across the grade/road from the Telegraph building, the Engine House being the closest to the parking area and containing a two-story portion with remains of a water tank, and the more distant one to the north being the Section House (or boarding house) ruin.

1.02 DESCRIPTION OF WORK

A. The principal features of work to be performed under these specifications at the

Engine House are:

1. Obtain analysis of historic mortar and sand source, and select appropriate mortar mix that matches the color and texture of the original. The Forest

Service shall approve the mix. If the local sand is not suitable, the contractor shall provide the sand and obtain approval for it.

2. Re-point or substantially repair failed masonry walls on the remaining, standing portions of two major buildings, the Engine House and the Section

House. Follow guidelines in the Attachments. Match historic workmanship.

3. Remove large brush (willows) from within the structures and plants growing within the masonry walls themselves. Approximate areas of brush to be removed is about 100 square feet.

4. Treat several large exposed major wood members in the stone walls of the building with wood preservative such as “Boracare” to retard decomposition.

(See Attachment 1 & 2. )

5. Construct a low gravel pathway to the center of the Engine House, and one to the south end of the Engine House ruin. (see Attachment 3). These will be raised about 20 inches above the ground level and be filled with rubble,

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Approximate lengths of the pathways is 50 feet.

All quantities should be verified on site by the Contractor.

1.06 SCHEDULE

A. Work shall be completed during the summer of 2010, and completed prior to

October 30, 2010.

END OF SECTION

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SECTION 010250

DEFINITION OF BID ITEMS AND MEASUREMENT AND PAYMENT

PART 1 - GENERAL

1.1 SUMMARY

A. Scope:

1. The project consists of re-mortaring and stabilizing ruined stone walls in two structures the Alpine Tunnel Historic District, and constructing short walking pathways into one of the structures, in addition to minor brush clearing.

B. Work:

1. Furnishing all labor, materials, equipment, and other incidentals necessary to successfully complete the project or any portion of it, and carrying out all duties and obligations imposed by the contract on the Contractor.

C. Payment:

1. For each individual item summarized and in the Schedule of Items listed in more detail, Payment shall be full compensation for all work related to the particular item in accordance with these specifications, as shown on the drawings, and as staked in the field.

2. Measurement and Payment for contract work shall be made only for and under those Bid items included in the Schedule of Items. All other work and materials shall be considered incidental or as included in the Payment for items shown.

1.2 DETERMINATION OF QUANTITIES

A. The contractor shall perform, or cause to be performed, all measurement of quantities of materials incorporated into the work processes that are to be measured under the provisions of the contract.

B. Quantity Measurements:

1. The Contractor shall make all measurements for computation of quantities for all work items except those specified for Payment by Designed Quantity (DQ) or Lump Sum Quantity (LSQ).

2. The Contractor shall compute the quantities for periodic progress Payments;

the Contracting Officer shall compute the quantities for the final Payment based on measurements taken by the Contractor.

3. All Contractor measurements are subject to verification.

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4. The Contractor shall submit all field notes, calculation sheets, and other data used to determine quantities.

5. The Contractor shall certify in writing as to the accuracy of the measurements and computations submitted.

C. The following measurements and calculations are used to determine contract quantities.

1. For items that are measured by the linear foot, such as pipe culverts, fencing, guardrail, and underdrains, measurements shall be made parallel to the base or foundation upon which the structures are placed. Pipes shall be measured along center of invert.

2. For aggregates weighed for Payment, the tonnage shall not be adjusted for moisture content, unless otherwise provided.

3. For standard manufactured items--such as fence, wire, plates, rolled shapes, pipe conduits--identified by gauge, weight, section dimensions, and so forth, such identifications shall be considered the nominal weights or dimensions.

Unless controlled by tolerances in cited specifications, manufacturer's tolerances shall be accepted.

1.3 UNITS OF MEASUREMENT

A. Payment shall be by units defined and determined according to U.S. Standard measure and by the following:

B. Each: One complete unit, which may consist of one or more parts.

C. Linear Foot: Linear feet measured horizontally.

D. Lump Sum: Do not measure directly. The Bid amount is complete Payment for all work described in the Bid item and necessary to complete the work for that item.

1.4 DESCRIPTION OF BID ITEMS

BASE BID ITEMS:

A. Base Bid Item – Engine house Stabilization

1. This bid item includes material and labor to stabilize the standing wall sections that are over 3 feet in height in this structure. Sections under three feet in height will not require stabilization. Sections to be stabilized consist primarily of the standing corners. The southeastern corner behind the collapsed wooden water tank is two stories high. Stabilization will consist of mortar and stone masonry work to maintain what wall is remaining without introduction of additional structural supports. Attention will be paid to the footings of the standing sections, and to water infiltration and support of unsupported stones. Sections of wall adjacent to two doorways shall be reconstructed 2-3 feet to define the openings visually; these section shall not be required over four feet on either side of the doorways.

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2. Payment shall be made at the contract lump sum price.

B. Optional Bid Item 001 – Section House Stabilization

1. This bid item includes material and labor to stabilize the standing wall sections that are over 3 feet in height in this structure. This is structure is smaller than the Engine House. Sections under three feet in height will not require stabilization. Sections to be stabilized consist primarily of the standing corners.

Stabilization will consist of mortar and stone masonry work to maintain what wall is remaining without introduction of additional structural supports.

Attention will be paid to the footings of the standing sections, and to water infiltration and support of unsupported stones. Sections of wall adjacent to one of the window openings in the northern wall shall be reconstructed 2-3 feet to define the openings visually; these section shall not be required over four feet on either side of the doorways.

2. .

C. Optional Bid Item 002 – Pathways Construction at Engine House

1. This bid item includes material and labor to construct two short 48” wide walking trail sections leading to viewing areas for the Engine House ruin. The work will require moving large and small stones out of the path, grading or clearing it, and raising the level of the path up to some 20 inches to maintain an

ADA accessible intersection with the main railroad grade/road. Local material may be used to form the base of this path, and it will be topped with commercial compacted aggregate. The sides of the pathways will be formed of stones to contain the fill material.

2. Payment shall be made at the contract lump-sum price.

3. This Bid item includes installing GFCI receptacle at NW side sink and repair inoperative exterior light on west deck.. It shall be measured as a lump sum quantity (LSQ).

4. Payment shall be made at the contract lump-sum price.

PART 2 - METHOD OF MEASUREMENT

2.1 GENERAL

A. One of the following methods of measurement for determining final Payment is designated on the Schedule of Items for each Bid item:

B. DESIGNED QUANTITIES (DQ)

1. These quantities denote the final number or units to be paid for under the terms of the contract. They are based upon the original design data available prior to advertising the project. Original design data include the preliminary survey information, design assumptions, calculations, drawings, and the

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Schedule of Items may be authorized under any of the following conditions:

a. As a result of changes in the work authorized by the Contracting Officer.

b. As a result of the Contracting Officer determining that errors exist in the original design that cause a Bid item quantity to change by 15 percent or more.

c. As a result of the Contractor submitting to the Contracting Officer a written request showing evidence of errors in the original design that cause a Bid item quantity to change by 15 percent or more. The evidence must be verifiable and consist of calculations, drawings, or other data that show how the designed quantity is believed to be in error.

C. ACTUAL QUANTITIES (AQ)

1. These estimated quantities which are determined from actual measurements of completed work.

D. LUMP SUM QUANTITIES (LSQ)

1. These quantities denote one complete unit of work as required by or described in the contract, including necessary materials, equipment, and labor to complete the job. They shall not be measured.

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SECTION 016000 - USE OF GOVERNMENT FACILITIES, UTILITIES, ETC.

1.01 Scope: Applies to Government facilities at the site available for use by the Contractor.

1.02 Storage Area: An area in the vicinity of the building is available for use as a storage area, however security of the storage area will be the responsibility of the Contractor.

1.03 Utilities: No utilities or water are available on site. A restroom is available.

Section 040513 - 9

SECTION 0l7l00

CLEAN UP AND DISPOSAL

1.1 CLEAN UP

A. The contractor shall keep the work site free from accumulation of waste materials and rubbish resulting from the work.

B. Before final acceptance of the project by the Government, the contractor shall remove from Government land all waste materials and rubbish resulting from this work, except that burnables may be piled at a designated disposal site for burning. All timbers that are removed from the structure shall be collected and stored at the Matterhorn Guard

Station at a location approved by the Contracting Officer's Representative.

1.2 DISPOSAL

A. Excavated material:

1. Excavated material that is excess to needs and reasonably free of muck, roots, and debris shall be disposed of at a location near the site designated by the Forest

Service.

B. Burnable Debris:

1. Burnable Debris (brush, wood, packaging). Haul to designated area. Do not burn without a permit.

C. Unburnable Trash and Garbage:

1. Haul to State-approved sanitary landfill.

D. Unusable Excavated Material:

1. Unusable Excavated Material (such as muck and roots) haul to designated disposal area.

E. Washing waste material down sewers or into waterways will not be permitted.

Section 040513 - 10

DIVISION 2 -

SECTION 022140

48” AGGREGATE PATHWAYS

PART 1 - GENERAL

3.1 SUMMARY

A. Includes furnishing materials, equipment, and labor to construct, 48 inch wide aggregate surface trails, shown on the drawing (Attachment 3).

PART 2 PRODUCTS

4.1 AGGREGATES

A. Aggregate for Base Course under asphalt shall be Class 6 as described in Section

02231 Aggregate Base or Surface Course.

B. Aggregate for surface course of 48” aggregate trials shall be #4 minus crusher fines with the following gradation or approved equal.

Sieve Size

Percentages by Weight Passing Square Mesh Sieves

3/8” inch 100

No. 4 85-100

No. 8 51-67

No. 30 22-34

No. 200 6-10

PART 3 – EXECUTION

5.1 TRAIL CONSTRUCTION

A. The trail shall be constructed at the locations shown on the drawings or as located by the Contracting Officer on the ground and as shown on the drawings.

B. Clear, grub, and dispose of trees, brush and vegetation within the clearing limits.

Section 040513 - 11

C. Strip and stockpile topsoil from excavation limits.

D. Uniformly grade the subgrade and slopes, taking care not to damage adjacent vegetation. The finished subgrade surface shall be reasonably level, smooth, compacted and free from irregular surface changes. Subgrade material shall be moistened or dried to a uniform moisture content suitable for compaction. Subgrades for aggregate surfaced and asphalt trails shall be compacted by a minimum of two passes with a mechanical tamper or until visible deformation ceases.

E. Place aggregate surface or base course material to uniform depths shown on the drawings and compact. Aggregate material shall be moistened or dried to a uniform moisture content suitable for compaction. Aggregates for surface or base course shall be compacted by a minimum of two passes with a mechanical tamper or until visible deformation ceases. .

F. After placement of surfacing, place topsoil over disturbed surfaces outside trail surface.

G. The area shall then be cleaned up by removing and disposing of all materials not utilized.

Section 040513 - 12

SECTION 040513 – RESTORATION MORTARING

GENERAL

1.01 Scope: Applies to mortars for use in the repair of unit masonry structures. Seee also directions on the Stabilization Plans, Attachment 1 & 2.

1.02 Storage of Materials: Store to prevent deterioration or intrusion of foreign material.

PRODUCTS

2.01 Mortar: The chemical makeup of the mortar mix shall be determined by the contractor after analysis of the historic material, before work begins. The mix shall be approved by the Forest Service. The mix used shall be physically compatible so as to prevent deterioration of the wall or the masonry units. It should also closely match the original in color and texture. It is aniticipated that local sand was used historically, and would be suitable for this purpose. The contractor may also use imported sand from off –site but must obtain Forest approval for the match.

EXECUTION

3.01 Mixing: Mix for at least 3 minutes to produce a workable plastic consistency. Mix only the quantity required for immediate use.

3.02 Retempering: Place mortar in final position within 2 hours after mixing. Retempering allowed within this time limit to restore required consistency.

3.03 Workmanship: It is crucial that the workmanship match or blend with the original historical workamnship in style of laying up walls and filling holes, in order to preserve the historical look of the building. Variations in moartar application are allowed only if they do not alter the historical workmanship. The objective is to preserve the structures in their current state of decay, not to restore or rebuild them.

Section 44300- 13

SECTION 044300 - STONE MASONRY

GENERAL

1.01 Scope: Applies to stone masonry work as specified herein. Rock is locally available from the collapsed walls.

1.02 Protection:

A. During erection, keep walls dry by covering at the end of each shutdown period.

B. During freezing weather, protect stored stone with tarpaulins or other suitable material.

1.04 Job Conditions: Do not lay masonry when the temperature of the outside air is below

40oF unless properly protected. Protect for 48 hours with Type I cement in the mortar;

24 hours for Type III cement. Protect at minimum 40oF, maximum 160oF temperature.

PRODUCTS

2.01 Native Stones: Stone shall match the existing stone and shall either be the same rock that fell off the wall or one very similar that is locally available.

2.02 Metal Ties: Zinc-coated corrugated metal not less than 7/8-inch wide, of sheet steel not lighter than 0.299-inch in nominal thickness (22 gauge) and not less than 6 inches in length.

EXECUTION

3.01 Preparation:

A. Do not perform masonry work in freezing weather or when masonry units contain frost.

B. Clean concealed portions of stones before setting.

3.02 Laying:

A. Use fresh, clean mortar. If it is possible to match the color of the existing mortar by adding an additive, obtain verbal approval from COR to accomplish that.

B. Any stone which is moved after being set shall be removed, cleaned, and set in new mortar.

D. Masons use judgment as to whether ties, which were not common in the original wall, are necessary. Attach veneer to backing with corrugated metal ties. Use

Section 44300- 14 one tie for each 2 square feet of wall area. Horizontal or vertical spacing shall not exceed 24 inches. Embed ties at least 2 inches in a horizontal joint of the facing.

Provide at openings additional ties spaced not more than 3 feet around the perimeter and within 12 inches of the opening.

E. Build in required items as the work progresses. Set lintels, capping units and like items in a full bed of mortar.

F. The mortar joint shall be constructed so that it is recessed 1" deep behind the face of the rock and the width of the joint shall not be less that 1/2 " nor greater than 1" unless to do so would not match existing masonry work.

3.03 Cleaning: Stone work shall be cleaned of excess mortar, etc., at completion of work.

Ground should be generally clear of spills of cement.