Palomas_Dam_Riprap_Statement_of_Work_0001.docx

Bureau of Land Management

1.0 Scope

1.1 Background

The Bureau of Land Management's (BLM) mission is to sustain the health, diversity, and productivity of public lands for the use and enjoyment of present and future generations.

1.2 Introduction

The dam was designed with a 10-foot-wide crest, an upstream (south side) slope of 3:1 and downstream slope of 2:1. The earthen structure is approximately 800 feet long and 15 to 17 feet high. There is a major 35-foot-wide breach of the dam, about 200 feet from its west end. This breach has cut through to below the keyed depth and created head cutting within the upstream reservoir area. Additional erosion has occurred near the west end, about 130 feet west of the breach.

Silts have deposited more than a foot deep upstream at the original 24-inch outlet pipe with riser and trash rack near the center of the dam; refer to Appendix B for photos of existing conditions. The corrugated steel pipe is in good condition although the asphaltic lining is cracked and peeling, and the downstream outlet is 90% occluded with silt.

The goal of this project is to eliminate the structure from classification as a dam, and to provide a grade control and energy dissipation spillway that will serve to heal the recent head cutting while passing all storms.

The proposed structure is an armored, long sag curve cut down along the crest of the dam, tapering in width from 10 feet to a maximum of 62 feet. The spillway slopes down at a maximum grade of 16:1 (horizontal to vertical) and flattens out at the center to provide a 300-foot wide, level plane for water to flow across as shallow sheet flow.

The top has a cross-slope toward the downstream at 0.01 feet per hundred (1%) and will be armored with concrete to an elevation of one foot above the estimated 500-year water surface elevation over the weir. Concrete cut-off walls on all sides will help resist water intrusion under the face of the weir. Cut-off walls on the upstream edge are 12” wide x 48” deep and dowelled to the top of the structure. On the side approaches and downstream edge, the walls are 36 inches deep.

Rock riprap embedded into the downstream edge of the top will dissipate energy where storm water exits the structure, to reduce scour. A dumped blanket of rock riprap is also placed on the downstream slope, within and between the existing vegetation, to armor this slope and dissipate flow energies down the slope.

1.3 Objective

Contractor will provide approximately 110 Tons of riprap to the U.S. Bureau of Land Management (BLM) in accordance with the technical requirements of this specification and all other general terms of the contract stipulated by the BLM Contracting Officer. Bidder shall be responsible for all labor and material to manufacturing, loading, and hauling of the riprap.

Delivery – Entire order to be delivered to destinations shown on attached map. Contract price shall include all costs associated with delivery, destination. Receiving facility’s normal hours of operation are Monday – Thursday, 8:00 am to 5:00 pm local time, except Federal holidays. The contractor shall coordinate the delivery dates with the contracting officer’s representative (COR).

1.4 Inherently Government Functions

No contractor shall perform any inherently governmental functions. No function described in this SOW is inherently governmental as defined in FAR 2.101 and FAR 7.5.

2.0 Applicable Documents

The following documents form a part of this SOW:

Statement of Work Attachment A- Pricing Schedule/Submission Attachment B – Location Map

3.0 Deliverables

110 Tons of riprap with a minimum D50= 6” - can be class G (wear edges not as angular)

3.1 Submittals

Submit DOT Classification G of angular riprap with a minimum D50 = 6”

3.2 Delivery Location and Period of Performance

3.2.1 Place of Delivery

Palomas Draw Dam #9 is in Luna County, New Mexico. The dam is about 18 miles south of Gage, New Mexico within Section 36, Township 26 South, Range 13 West. The site may be accessed from Gage on CO20 to CO19, both dirt roads. The dam sits on New Mexico state land that is also rangeland managed and maintained by the US Bureau of Land Management (BLM).

3.2.2 Period of Performance

Anticipated Delivery Dates: September 4, 2023 – October 4, 2023. Delivery should be coordinated after award and completed within 30 days of initiation.

3.2.2.1 Holidays

The Government observes the following holidays:

· New Year's Day, January 1

· Martin Luther King's Birthday, the third Monday in January

· President's Birthday, the third Monday in February

· Memorial Day, the last Monday in May

· Independence Day, July 4

· Juneteenth Day, June 19

· Labor Day, the first Monday in September

· Columbus Day, the second Monday in October

· Veteran's Day, November 11

· Thanksgiving Day, the fourth Thursday in November

· Christmas Day, December 25

4.0 Payment

Contractor shall submit a lump sum invoice for full payment for the Class G angular riprap received by the BLM at the end of the project. Invoiced amounts shall be supported with copies of dispatch tickets and should be submitted to the Contracting Officer’s Representative, COR with the invoice for review and concurrence. After approval is giving, the contractor shall submit an electronic invoice via the Internet Payment Platform (IPP.gov) for payment.

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