A06__SPRNCA_Boundary_Fence_Specs_-_DRAFT_1.docx

Construction Specifications Bureau of Land Management - Tucson Field Office San Pedro Riparian National Conservation Area (SPRNCA) Boundary Fence Reconstruction Phase 1A Introduction Phase 1A of the San Pedro Riparian National Conservation Area (SPRNCA) boundary fence project requires approximately 4.86 miles of reconstruction and maintenance to conserve, protect, and enhance the SPRNCA conservation values outlined in Public Law 100-696. The proposed work will occur entirely located on BLM managed public land (See Figure 1) and will reconstruct this partially connected and non-functioning (due to age of the existing fence, topography, weather damage) fence. Reconstruction of the fence will include vegetation clearing; installation of T-posts; stress, stretch, end and corner panels; installation of panel gates; and removal of non-functioning fence, remnant fencing or unused materials. Fence reconstruction would follow the specifications in BLM Manual H-1741-1 and Arizona Game and Fish Department wildlife-friendly standards for a four-wire fence with stays. Wire spacing will be 16”, 22”, 30” and 42” with the bottom wire being smooth and top three barbed (Figure 14).

The topography of this phase of the project contains dense vegetation of whitethorn and creosote shrubs with some lower drainages having larger mesquite trees. Water flow from the uplands to the SPRNCA contains multiple drainages that have steep elevation changes. The steep slopes may have heavy rock cover. Construction of the large Willow Wash water gap structure will be under a separate contract. The remaining smaller drainages will require bracing outside of water flow paths to prevent damage during flows. Climate for the area depends on the time of year but can get below freezing in the winter months to over 100 degrees in the summer. Monsoon season begins mid-July and runs through September. Storms are most common in the afternoon, but large, unexpected storms can happen at any time.

Access to and along the fence line may be by foot, UTV, skid steer or vehicle. A fence buffer of 30 feet is divided into 15 feet on each side of the surveyed line; however, access along the fence line may be restricted to the 15 feet on the BLM managed land. The BLM will survey and mark the SPRNCA boundary fence line. Fence replacement must follow the survey line as accurately as possible. Phase 1A northern access is from Highway 80 at Curtis Windmill. The southern access is from Highway 82 near mile marker 60 (Figure 1).

Equipment needed to implement construction may include trucks, equipment trailer, UTV, skid steer loader (hydraulic driver, possibly mower, bucket), backhoe or excavator, and/or pneumatic drivers.

General Information and Requirements Existing fence removal and new fence reconstruction of the 4.86 miles indicated below.

A. Description of Work:

a. Fence Removal- Contractor shall furnish all labor and equipment necessary to remove approximately 4.86 miles of 4 strand barbed wire fencing including posts and end, stress, and brace panels. All debris, including wood posts, poles, steel posts, and wire, becomes the property of Contractor and must be removed from the work site. Contractor shall be responsible for disposal of all debris in a legal manner and payment of any fees required. Burning of debris is not permitted on the work site.

b. Fence Construction- Contractor shall furnish all labor, equipment, supplies and materials, except specified government furnished property, to reconstruct 4.86 miles of 4 strand barbed wire fences and gates. Construction of the 4 strand barbed wire fence will include installation of stress panels, end panels, corner panels and steel gates.

B. Schedule: A project initiation meeting shall occur prior to the start of any construction activities to establish a schedule for project completion. Contractors shall provide regular progress updates to the BLM Project Manager on a weekly basis. Schedule operations, so that work is generally conducted between 06:00 and 18:00, Monday through Friday, except Federal Holidays or as otherwise approved in writing by the Contracting Officer (CO) to avoid disturbing nearby residents.

C. Location: Work under this contract is in Cochise County, State of Arizona. The work location for Phase 1A is shown on Figure 1: SPRNCA Fence Reconstruction Phase 1A and is between Highway 82 and Summers Well Entry Corral. Some roads may cross land not under the jurisdiction of the BLM, and other routes do exist. In the Public Land Survey System, the project is within Township 19S, Range 21E, Sections 9,15, 16, 22, 27, 34 and 35. Cochise County, Arizona.

D. Trash Disposal: Pack all trash generated by the Contractor out of public land and disposed of at an approved land fill facility. No trash or litter shall be allowed to accumulate on the grounds. Trash shall not be buried on public land. Collect, contain, haul, and dispose of litter and debris generated daily by the Contractor, and dispose of in accordance with all federal, state, and local laws and regulations regarding construction waste. Burning of trash is prohibited.

E. Environmental Considerations: Do not conduct fueling operations on site. Excavate any fuel or oil spills occurring during the work of this project to a depth of 12 inches beyond contaminated material and removed from the work location in accordance with federal, state, and local regulations. Operate vehicles and equipment within existing roadways and parking areas. Upon completion of the contract, remove all trash and construction waste materials that include erosion control measures. Furthermore, smooth any areas of earth grossly disturbed by the Contractor’s operations in the opinion of the COR/PI.

F. Prevention of Invasive Noxious Weeds: Before entering BLM land, the Contractor shall power wash/rinse off its equipment to reduce greatly the possibility of introducing invasive noxious weeds. If invasive noxious weeds still become established within the project area, implement control methods to limit propagation. Invasive noxious weeds that become established shall be monitored for the duration of the contract and reported via documentation submittal to the BLM, which especially includes Johnsongrass, bull thistle, tamarisk, cocklebur, and any others that have not been documented previously in the project area.

G. Safety and Quality Control Plans: Within 10-days following contract award, Contractor shall provide to the Government effective quality control and safety plans for acceptance by the BLM.

H. Fire Season: Contractor shall comply with all applicable state and federal laws relating to fire prevention and special conditions of work as directed by the Government.

I. Cultural Resource Protection: If in connection with operations under this authorization, any archaeological or historical artifacts, human remains, funerary objects, sacred objects, objects of cultural patrimony as defined in the Native American Graves Protection and Repatriation Act (PL 101-601; Stat. 3048; 25USC 3001) are discovered, stop operations in the immediate area of the discovery, protect the remains and objects, and immediately notify the CO of the discovery. Continue to protect the immediate area of the discovery until notified in writing by the CO that operations may resume. Allow access to the archeologist for visual inspections of the project site during the progress of work.

J. Drawings: Drawings in this document are general only and dimension of each structure will be fixed by the Government to adapt the design to existing conditions at the structure location. Dimensions may be provided in the written instructions under Installation.

K. Access: Transportation and access within the SPRNCA will be managed in accordance with the 2019 SPRNCA Resource Management Plan Record of Decision. Nearest towns include Benson and Tombstone. The entrance for the northern end of the project is just west of Curtis Windmill on state Route 80 about one-quarter mile south of mile post 309. The Summers Well corrals are 2.8 miles west of this entry and travel is through AZ State Trust Land (Figure 1).

1. Terrain: The current fence line runs through rough and rocky terrain (Figure 2). Vegetation includes whitethorn and creosote shrubs in the uplands. Drainages may contain mesquite. Smaller vehicles such as UTVs will be the primary vehicles along the fence line. Vehicle access along the fence on slopes over 16% will be avoided as much as possible to reduce impacts and potential for erosion. Four-wheel drive vehicles will have difficulty accessing most fence line.

2. Access routes will be flagged by BLM. All travel must be restricted to these areas only.

3. Travel will be restricted to the 30 feet fence buffer along the fence line. The 30-foot fence buffer is divided into 15 feet on each side of the surveyed line; however, access along the fence line may be restricted to the 15 feet of buffer on the BLM managed land.

4. With permission from the Government, sand and gravel washes may be used to access the worksite. The wash must be wide enough for passage by work vehicles without clearing or removing vegetation or constructing a grade.

5. During construction unauthorized vehicle access along the fence line must be blocked or gated to prevent unauthorized traffic and promote revegetation and stabilize soils after the project is completed.

6. Contractor shall restore roads damaged by Contractor, at the Contractor's expense, to the same condition as prior to the commencement of work.

7. After construction is completed, the contractor shall post a “This is not a road” sign at the newly cleared entry points from major roadways. This is to prevent unauthorized traffic and promote revegetation of the area and stabilize soils after the project is completed.

8. The BLM will survey and mark the legal boundary lines. Survey markers will be set at a minimum of every quarter mile prior to construction.

9. Lodging: There will be no camping permitted at or near the work site. There are lodging and refueling options in Sierra Vista, Whetstone, Tombstone and Benson, AZ. There will be no above ground fuel storage onsite and no electricity. Cell coverage is limited in some of the lower elevations near site.

Statement of Work A. Materials: Contractor shall furnish all wire and fencing materials needed to complete 4.86 miles of fence according to type and specifications of materials listed below: Any substitutions must be approved by the BLM assigned COR.

1. Barbed Wire shall be 12.5-gauge galvanized wire with 2-point barbs of 14-gauge wire spaced 4 inches apart. Wire and barbs shall be zinc-coated steel with a zinc coating of at least 0.3 oz/ft2 of coated surface area. The minimum breaking strength of each wire shall be 950 lb-force. The barbed wire shall conform to ASTM A121.

2. The bottom strand of wire shall be 12.5-gauge barbless wire, galvanized wire. Wire shall be zinc-coated steel wire with a zinc coating of at least 0.3 oz/ft2 of coated surface area. The minimum breaking strength of each wire shall be 950 lb-force. The barbless wire shall conform to ASTM A 121.

3. Wire Fence Stays shall be manufactured from smooth galvanized 9-gauge wire centered between T-posts.

4. Steel Fence T-Posts shall be steel green with white or silver tops, “T” bar type, with a welded or riveted anchor plate. Steel T-posts shall be manufactured from wrought, rail, or new billet steel, and shall have a minimum weight of 1.33 lb/linear foot. The height of post can vary depending on soil depth. Six-foot-long T-posts are required at 16.5-foot spacings. With approval of the COR, 5-1/2-foot-long T-posts may be used in hard or rocky soils. The T-posts shall conform to ASTM A702.

5. Only clip-type wire fasteners will be permitted. Punched tabs for fastening wires are unacceptable.

6. Steel Panels and Braces: Contractor shall install stress panels every quarter mile and with any change of direction of the boundary. Additional bracing may be needed before and after drainages to create a water gap. Contractor shall cap the tops of each exposed pipe.

7. Contractor shall use Steel Pipe. Steel Pipe must be 2 3/8-inch o.d. schedule 80 steel pipe that is new or ones with best used condition of greater than 80% wall life.

8. Gates: One gate will be needed at the northern entry. Standard design for entry gates into the SPRNCA must include locking devices on each gate that do not require chain and help prevent lockouts from other users. Figure 3 includes two different designs: one with a slide design and one with a wheel design. These are provided as examples only. Inclusion in this document does not represent an endorsement of either system.

9. Current fencing shall be removed and recycled or disposed of in approved landfill. Contractor may keep recycling proceeds. The metal in the existing infrastructure, while old, has significant weights.

10. Project site shall be cleaned daily. All refuse must be removed by Contractor. Contractor shall dispose of materials and be responsible for all expenses incurred with disposal in accordance with all federal, state, and local laws and regulations.

B. Execution

1. Environmental Considerations:

a. Cultural: Contractor shall immediately suspend all operations in the vicinity upon discovery of any possible historical, archeological, or paleontological artifacts (such as historical ruins, graves, fossils) until authorized to proceed in writing.

i. Contractor shall immediately notify the COR in writing with the location and nature of the findings. No objects of cultural resource value may be removed.

ii. Contractor shall be responsible for protecting the discovered cultural resources from damage. Contractor shall be liable for all damage to discovered cultural resource caused by their actions or the action of their agents or representatives.

iii. The BLM will conduct a cultural survey in the fence buffer prior to construction.

b. Clearing and Grubbing: Contractor shall clear brush and trees with manual and powered hand tools along fence buffer. Clearing will be held to only that necessary to allow construction of the project and no larger than the fence buffer. Removal of all vegetation and root stubs along the fence buffer will prevent tire damage and allow for long term use of this fence line for maintenance. Disburse removed vegetation by scattering away from the project line.

c. Wildlife: BLM will conduct a pre-work bird survey to identify presence of migratory bird nests. Construction work will be prohibited during nesting season in critical habitat. Contractor will be notified of any restrictions prior to start of construction.

2. Removal of Existing Fence: Contractor shall remove all existing wire, end, stress, and corner panels, and gates as staked in the field or as designated by the Government. All debris, including wood posts, poles, steel posts, and wire, becomes the property of Contractor and must be removed from the work site. Contractor shall be responsible for disposal of all debris in accordance with all federal, state, and local laws and regulations. Burning of debris is not permitted on the work site.

3. Installation:

a. General: Contractor shall construct fences as described in the specifications and along the fence line as flagged in the field by BLM.

b. Driving Posts: Any post (T- post or tubular posts) damaged by pounding (e.g. split, bent, twisted, or mushroomed tops) will be rejected and replaced at Contractor’s expense. Drive steel posts into the ground so the T-post remains 48” above ground. The anchor plate must be below the ground surface.

c. T-posts spacing: T-posts shall be a maximum of 16.5 feet apart. The Government may approve spacing up to 20 feet apart in extremely rocky soils. Any soils that don’t permit driven posts can be relocated to the nearest practical location.

d. Corner panels (Qty:2): Corner panels shall be installed where the fence changes of direction. There are two locations that need a corner and are identified. Three steel pipe posts 9 feet long with a minimum of 2-3/8 inches o.d. shall be driven five feet into the ground for a final height of four feet (48 inches). At a minimum of 6 feet on either side of each 9-foot pipe post, a 5-foot post shall be driven to one foot. A welded kicker at 45-degrees between the shorter and longer posts ensures long term structural integrity. Fence wire shall be secured at both ends of braces and panels as shown in Figure 4. Unstable corner panels will be rejected and replaced at Contractor’s expense. All open ends of the pipe shall be capped.

e. Stress Panels (Qty: 151): Stress panels shall be constructed every quarter mile (80 rods) center-to-center for barbed wire sections and at points between which wire is to be stretched. Stress panels shall be installed at the top and bottoms of hills (Figure 5). Stress panels may be used in crossing small drainages as approved by the Government. Each stress panel will consist of a single large brace panel installed in alignment with the fence. In-Line Pull Post assemblies are recommended in straight sections of the fence line and where there are sudden changes in elevation, such as the bottom and top of steep slopes greater than eight (8) percent (Figures 6 and 7). Nine-foot-long posts driven five feet into the ground for a final height of four feet (48 inches). At a minimum of six feet on either side of each nine-foot pipe post, a five-foot post shall be driven to one foot. A welded kicker at 45-degrees between the shorter and longer posts ensures long term structural integrity. Fence wire shall be secured at both ends of braces and panels as shown in Figure 3. Unstable stress panels will be rejected and replaced at Contractor’s expense. All open pipe ends shall be capped.

f. End Panels (Qty: 8): Shall consist of a large and small brace panel installed in alignment with the fence. Construct end panels at the end of fence runs shown on Figure 8 with pipe dimensions as described for stress panels. End panels will be constructed at each gate. Each main post will be nine-foot-long driven five feet into the ground for a final height of four feet (48 inches). At a minimum of six feet on the necessary side of the nine-foot pipe post, a five-foot post shall be driven to one foot. A welded kicker at 45-degrees between the shorter and longer posts ensures long term structural integrity.

g. Small Water Gaps (Qty: 34): Figures 9-13 are examples of permitted fence types to be installed at small drainage crossings.

h. Large Water Gaps (Qty:7): Willow Wash Water Gap has existing pipe structure that will be utilized but new cable and hanging fence will be constructed. Figure 15 is the design preference for longer length water gaps.

i. Wire: All wire shall be tightly and uniformly stretched and shall be securely attached to steel posts with standard wire clips. Wire is properly stretched when it is springy to the touch. Terminate wire at each end panel or corner panel by wrapping wire around the post two times and tie off by wrapping the incoming wire a minimum of four times. Wire spacing will be 16”, 22”, 30” and 42” with the bottom wire being smooth and top three barbed (Figure 14). One wire stay per panel shall be centered between posts.

j. Gates (Qty: 3): Gates shall be attached to end panels or corner panels. One gate needed is required to replace an existing fence at the historic Summers Well corrals along an existing roadway. The Contractor shall use Steel Frame Gate design (top illustration Figure 16).

MEASUREMENT AND PAYMENT

A. Units: Wire fence will be measured and paid for by the linear foot of fence as measured along the ground surface next to the completed fence, including distance across gate openings, end panels, stress panels, corner panels, and small water gaps. The quantities of end, stress, and corner panels, gates and large water gaps are to be paid based on the actual number of these items. Note: Gates do not include adjacent end or corner panels. These are separate items. Fence removal will be paid as a lump sum.

Figure 1: SPRNCA Fence Reconstruction Phase 1A Map.

Figure 2. Examples of project terrain.

Figure 3: Examples of lock types for gates.

Figure 4. Standard post and barbed wire fence end

Figure 5. Stress panel braces for elevation changes.

Figure 6. Pull Panel design. Do not use concrete. Posts are to be driven 5 ft below ground as described in the above section on “Installation”.

Figure 7. Stress Panel design. Do not use concrete. Posts are to be driven 5 ft below ground as described in the above section on “Installation”.

Figure 8. End panel design. Do not use concrete. Posts are to be driven 5 ft below ground as described in the above section on “Installation”.

Figure 9. Stone deadman example.Figure 10: Small water gap fencing example.

Figure 11: Small water gap fencing example.

Figure 12: Small water gap fencing example.

Figure 13: Small depression fencing example.

Figure 14: Wire guide example.

Figure 15. Large Water Gap design.

Figure 16: Gate designs. Contractor shall use Steel Frame Gate design (top illustration.

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