SOW_Cargo_Mountains_AML.docx

2015 Cargo Mountains AML Remediation Project El Centro and Palm Springs Field Offices

SECTION C –

DESCRIPTION/SPECIFICATIONS/STATEMENT OF WORK

C.1.0 PROCEDURES

Contractors wishing to bid on this contract are encouraged to attend a pre-bid site visit. The Contracting Officers Technical representative and technical advisor will be leaving from the Gold Rock Ranch & Tumco exit located on the east side of Ogilby Road, TUMCO CA, on June 30, 2015. Departure time is at 9:00 a.m. A detailed map will be provided at the walk through and may be requested by sending an email to Sterling White (swhite@blm.gov).

If interested in the project, contractors shall submit a price to the contracting officer (CO) in response to the scope of work, per the schedule of items of the contract. There are biological restrictions for the work, i.e. bat maternity season. The maternity season typically last between April 1 to September 1. The period of performance will be one year from the award date.

Contract Time, The BLM Contracting Officer will issue a Notice to Proceed as soon as conditions are favorable for remediation to occur.

C.2.0 CONTRACTOR

The Contractor shall furnish all personnel, facilities, equipment, materials supplies, and services (except as may be expressly set forth in this contract as furnished by the Government), and otherwise do all things necessary for, or incident to, the satisfactory performance of this contract. Under this contract, the Contractor shall provide the items of work required to remediate physical safety hazards associated with Abandoned Mine Lands (AML). Nothing in this contract calls for work associated with the removal of hazardous materials (as defined by 49 CFR 105.5 (b)), or reclamation of lands which fall under the authority of the Comprehensive Response Compensation Liabilities Act (CERCLA) or the Resource Conservation and Recovery Act.

C.3.0 REQUIREMENTS AND SPECIFICATIONS

C.3.1 Road Access.

The Contractor may access the project areas from roads indicated on the project maps. BLM will help identify access into each site. Contractors shall note that road conditions may be poorly maintained and should be reviewed for equipment access prior to attempted delivery to a project site.

C.3.2 Site Access.

The Contractor shall transport equipment, supplies and personnel from existing trails and/or roads to the AML features. Access into work areas may be limited in some cases. The Contractor should consider using small vehicles such as All-Terrain Vehicles (ATVs) to accomplish the work. All trail or road improvements shall obtain COR approval prior to construction. All mines are to be surveyed for person(s) living in the mines prior to construction.

C.3.3 Polyurethane Foam (PUF) A PUF closure consists of installing a bottom form, then installing PUF to specifications and backfilling over the PUF to the specified level with common fill (2-feet or more unless otherwise specified). In some instances a cast-in-place concrete slab, rock armoring, or construction of a rock wall may be used to prevent vandalism. Reclamation of disturbed areas may also be specified by the COR.

C 3.3.1 Materials PUF is designed for molding and void filling applications. Co-blown (245FA solvent and water) foams shall have a minimum core density of 2 pounds per cubic foot, closed cell content greater than ninety percent, compressive strength greater than twenty five pounds per square inch, and a minimum installed density of 1.85 pounds per cubic foot. Water (100%) blown foams shall have a minimum core density of 2.5 pounds per cubic foot, closed cell content greater than ninety percent, compressive strength greater than twenty eight pounds per square inch, and a minimum installed density of 2.0 pounds per cubic foot. Either system is ideally 1:1 by volume however pre-metered bags could use an off ratio system. Exothermic reaction rates shall be low for both systems.

C.3.3.2 PUF Safety, Handling and Transport Materials shall be stored per the manufacturer’s specifications. The Contractor shall be responsible for any lost or damaged equipment. In addition damages or claims arising from PUF overspray shall be the responsibility of the Contractor.

C.3.3.3 Backing and Bottom Forms An adit plugs backing or a shaft plugs bottom form and cross members shall consist of any commonly available building materials capable of sustaining an initial lift of 16 inches of PUF. Any combination materials listed in the material table will be acceptable. Alternate materials will be acceptable upon approval by the COR.

When a form is used to support the initial layers of foam, the bottom form and cross members may consist of any commonly available, non-toxic building materials capable of sustaining an initial lift of 16 inches of PUF. Acceptable cross member materials include, but are not limited to, reinforcing steel, 2x4's, dowels, cardboard tubes, and fabric air-inflated plugs. Acceptable bottom form materials include, but are not limited to, plywood, cardboard, paneling, and carpeting. Any combination of the above materials will be acceptable. Alternate bottom forms shall be reviewed with the COR prior to use. The formwork shall be installed at the depth in accordance with the manufacturer’s formula. The depth shall be approved by the COR prior to any formwork.

All forms shall be completed prior to the application of any PUF. The Contractor shall provide the COR with the installed depth to bottom forms for PUF closures. Any breach in the form caused by rock fall or other reason shall be repaired prior to the application of PUF. The Contractor shall be responsible for the integrity of the form and the loss of any polyurethane should it fail.

C.3.4 Portal closures with Wildlife-friendly Gates and Cupolas (Appendix 2-5) This work will consist of fabricating and installing a special gate consisting of steel bars with an inset series of gaps to allow for bat ingress and egress while excluding public access. All gates shall have a removable bar with a locking device.

When work is being performed on shafts or adits with winzes (internal vertical shafts) workers must wear personal protective fall protection equipment including: a harness system and necessary attachments that meet OSHA fall protection requirements.

C.3.4.1 Materials Gates shall at a minimum consist of:

· 4-inch x 3/8-inch steel angle iron for horizontal bars

· 6-inch x 3/8-inch steel angle iron for horizontal bar hangers

· 4-inch by 3/8-inch steel square tubing for gate columns

· 4-inch by 1/4-inch flat bar for bracing

· Rebar metric Size 25 or Standard #8

· structural steel channel iron, 6-inch by 10.5 pound per foot (lb/ft)

· be constructed of structural steel that conforms to the requirements of ASTM A-36 (all purpose steel) or ASTM A276 (stainless steel); or better.

Structural “I” Beam

· be constructed of structural steel that conforms to the requirements of ASTM A36 / A572 Gr. 50, the standard specification for steel structural shapes for use in general construction.

Wood Lagging

· 3x10 or 3x12 sawmill rough cut lumber

C.3.4.2 Gate Installation:

The Contractor is responsible for site inspections and any testing or exploration necessary to ensure that the bid adequately reflects excavation conditions including any hand trimming and leveling required.

The work site shall be cleared and grubbed of vegetation, debris, loose rocks and other items which interfere with construction except items designated by the COR/PI. All trash and debris shall be disposed of at an approved disposal site.

Gates attached to Adit Walls - Wildlife-friendly gates shall be held in place by anchors that have been sunk into competent bedrock. At minimum, one anchor per column will be placed in the floor and ceiling of the mine and one anchor per side of the gate will be placed in the adit walls. Horizontal anchor attachments shall be spaced at 33% and 66% of the height for gates taller than 48 inches, as a general guideline. End anchors must be used on bars that extend more than 30 inches beyond the columns. Anchor holes will be drilled to a depth no less than 6 inches and should be 1-inch or metric equivalent in size. A Metric #25 rebar, or an equivalent steel substitute shall be driven to the depth of each hole and used as the anchoring mechanism. Standards for hole depth, size, and material shall be the same as specified herein.

Channel iron (6”x10.5 lb/ft) spanning the width of the adit floor with pre-cut holes shall be placed tabs down over the anhors and welded in place. Six inch angle irons cut to a length of 6 inches with pre-cut holes are welded to anchors in the ceiling. Columns of the gate shall be welded into place.

Horizontal bars, evenly spaced with gaps equal to 5¾-inch intervals extending to the adit walls are welded in place on Contractor made hangers of each column. A removable horizontal bar with a hidden latch and shrouded (boxed-in) lock is required. Contractor shall furnish locks shall consist of a tamper-resistant bolt similar to the “MacGuard” bolts or equivalent. To finish the gate, a 4 inch flat iron is welded on the back of the horizontal bars.

Unless otherwise specified, gates are not coated, but any coatings that are applied should be brushed on, not sprayed, to avoid volatiles from entering the cave unless, the steel is pre-coated prior to construction. Adit and cave gates usually are constructed during a season when bats are not vulnerable, or when air is flowing out of the entrance.

Cupola Installation:

The Contractor is responsible for site inspections and any testing or exploration necessary to ensure that the bid adequately reflects excavation conditions including any hand trimming and leveling required.

The work site shall be cleared and grubbed of vegetation, debris, loose rocks and other items which interfere with construction except items designated by the COR/PI. All trash and debris shall be disposed of at an approved disposal site.

The location for a Wildlife-friendly cupola (typically 4-sided and 3 horizontal bars tall) shall be constructed on the perimeter of the mine shaft opening and attached to a concrete foundation (can also be referred to as a cast-in-place collar). A minimum of two concrete anchors shall be used per each side of the foundation. The depth and thickness of the concrete foundation shall be poured to a thickness of no less than 10-inches with at least 6-inches below the surface; exceptions may be made with prior COR approval. This will help prevent water from flowing under the foundation. The concrete may be mixed at the work site or delivered as ready mix at the Contractors option. If the concrete is mixed on site, equipment and mixing procedures shall conform to ACI 301. If ready mix is used it shall be mixed and transported in accordance with ASTM C-94. The concrete mix shall be designed to produce a minimum 3000 psi concrete at the 28 day test. If hot weather concreting is done it shall conform to the requirements of ACI-305. If cold weather concreting is done it shall conform to the requirements of ACI-306. The rate of depositing concrete in forms shall be controlled to prevent deflection of the form panels.

A sill plate consisting of 4-inch flat iron spanning the length and width of the foundation with pre-cut holes shall be placed on top of the concrete anchors and welded in place. This flat iron serves as the sill plate in preparation for the cupola attachment. The cupola columns are made of 4 inch square steel tubing is welded to the sill plate. Intermediate uprights that are not at the corners of the cupola can be made of angle iron. Horizontal bars, evenly spaced with gaps at 5¾" intervals extending the same length as the sill plate, are welded in place on Contractor-made hangers of each column. A removable horizontal bar with a hidden latch and shrouded (boxed-in) lock is required. Generally, locks shall consist of a tamper-resistant bolt similar to the “MacGuard” bolts or equivalent.

The Contractor will be responsible for determining where the columns and intermediate columns will be placed and welded on top of the sill plate; and for structure roof support. The roof of cupola’s less than 24 inches tall shall be capable of holding a point load of 6,000 pounds at the center of the roof. Cupola’s greater than 24 inches tall shall be capable of holding a point load of 2,000 pounds at the center of the roof. Where possible, support columns should be placed perpendicular to level, no closer than 24 inches apart while maximum spacing should not be more than 120 inches.

To finish the cupola’s roof, structural iron spanning the two longest sides of the cupola and support beams are cut to length, mounted flush to the tops of the columns, and welded along each seam of the upright columns. Welded beads should be no shorter than 2 inches in length. Face plates are either 4 or 6-inch flat irons welded to the ends of the beams or channels to provide the finished look and ties the roof structure together. The cap plates are welded on top of the ends of the beams, perpendicular to the face plates. Cap plates can be either 4-inch or 6-inch flat iron depending on the dimensions of the top of the cupola and the efficiency of materials. Three pound (3 lb.) expanded metal cut-to-fit is then placed on top of the cupola and welded in place.

El Centro Field Office within the area known as the Cargo and Chocolate Mountains; and in the Palm Springs Field Office area known as the Maria Mountains.

The terrain is rough; the access roads into these project locations require high clearance vehicles with off-highway tires and a good set of driver skills. Interested parties wishing to participate in the walk through are encouraged to bring good hiking gear, sun protection, water, and food.

ITEM LIST FOR THIS CONTRACT

The work to be performed is within the BLM’s California Desert District (CDD).

Starting point for the project job walk (Map):

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