Performance Work Statement (PWS)

FY26 Spillway Drainage Inspection Garrison Dam, ND

Contents

1. Background

1.1 PWS Summary and Purpose

1.2 Drainage Systems Description

1.3 Site Access

2. General Contract Information

2.1 Period of Performance

2.2 Government Furnished Items and Services

2.3 Contractor Furnished Items and Services

2.4 Contractor POC’s

2.5 Government POC’s

2.6 PWS Modifications

3. Description of Services

3.1 Task 1 - Flush, measure sediment, camera and report for Rows 2-9 spillway subdrain (14,060 ft)

3.2 Task 2 – Flush, measure sediment, camera and report for Row 1 spillway subdrain (2,120 ft)

3.3 Task 3 – Flush, measure sediment, camera and report for spillway box drains (4,800 feet)

3.4 Task 4 – Sounding, camera and report for crest relief wells

3.5 Task 5 – Temporary Chute Access Staircase

3.6 Task 6 - All Other Work

3.7 Task 7 (Option 1) – Flush, measure sediment, camera and report for power plant drainage (5,295 feet) ... 16

4. Contractor Requirements

4.1 Submittal Register and Schedule

4.2 Work Plan, Quality Assurance and Control

4.3 Pre-Work Meetings

4.4 Performance Requirements Summary

4.5 Safety, Standards and Regulations

4.6 Antiterrorism/Operation Security Requirements

Attachments Attachment 1 – Reference Drawings

1. Background

1.1 PWS Summary and Purpose

This Performance Work Statement describes a scope of work and requirements for cleanout and camera inspection of the Garrison Dam spillway subdrains, the spillway adjacent box drains, the spillway crest relief wells, and the powerhouse under seepage drains. The objective of this project is to gain a better understanding of the condition of these features, informing design of future dam safety modifications, and to rehabilitate them as effectively as possible to maintain project performance and safety.

For the purpose of defining price schedule and performance requirements, the work has been divided into 6 tasks:

Task 1 - Flush, measure sediment, camera and report for Rows 2-9 spillway subdrain (14,060 ft) Task 2 – Flush, measure sediment, camera and report for Row 1 spillway subdrain (2,120 ft) Task 3 – Flush, measure sediment, camera and report for spillway box drains (4,800 feet) Task 4 – Sounding, camera and report for crest relief wells Task 5 – Temporary chute access staircase Task 6 – All Other Work Task 7 (Option 1) - Flush, measure sediment, camera and report for power plant drainage (5,295 feet)

Tasks 1 through 4 are located around the Garrison Dam spillway at the dam’s east abutment, while Task 7 is located outside of the project powerhouse near the west abutment. An overview map is provided in Figure 1.

Figure 1. Garrison Dam overview map.

1.1.1 Garrison Dam Background

The Garrison Dam – Lake Sakakawea Project was authorized by the Flood Control Act approved 22 December 1944, as part of the comprehensive plan for flood control and other purposes on the Missouri River Basin. The authorized purposes include flood risk management, hydroelectric power, water supply, water quality control, irrigation, recreation, navigation, and fish and wildlife. The dam was constructed primarily between 1947 and 1954.

Major project components include the earth-fill dam embankment, hydroelectric generating plant, and the concrete spillway.

In 2011, the Missouri River Mainstem Reservoir System experienced record runoff and inflow into reservoirs that led to the inaugural use of the Garrison emergency spillway for flood control purposes. Issues with spillway chute underdrain system were observed after multiple manhole covers were removed from the spillway chute slab by flow during spillway operation.

Post-flood inspections, repairs, risk assessments, and studies resulted in approval to initiate design of a Garrison Dam Spillway Modification in 2023. The spillway modification design is intended to include abandonment of the existing subdrainage system and construction of a replacement subdrainage system.

1.2 Drainage Systems Description

An overview map of the spillway drainage systems is shown in Figure 2. Additional details are provided in Attachment 1.

Figure 2: Subdrain and Box Drain Layout

1.2.1 Chute slab subdrains, general

The subdrainage pipe network is accessed from 29 manholes located within the spillway chute. The manholes are on a network of Rows 1 through 9 and outfalls “W”, “C”, and “E”. Row 1 has two additional manholes labeled MH-WS and MH-ES. The network of vitrified clay pipe segments between the manholes are listed in Table 1.

Table 1: Chute Subdrain Lengths

From To Pipe Diameter (Inches)

Approx. Pipe Length (Feet) Pipe Type “Row 1”

MH-W1 MH-WS 12 175 VC Perforated X MH-W1 MH-W2 12 285 VC Perforated X MH-W2 MH-W2E 12 208 VC Perforated MH-W2 MH-W2W 12 220 VC Perforated MH-W2 MH-W3 12 305 VC Perforated/CIPP MH-W3 MH-W3E 12 182.5 VC Perforated/CIPP MH-W3 MH-W3W 12 182 VC Perforated MH-W3 MH-W4 15 300 VC Perforated MH-W4 MH-W4E 12 163 VC Perforated MH-W4 MH-W4W 12 151 VC Perforated MH-W4 MH-W5 15 310 VC Perforated MH-W5 MH-W5E 12 151 VC Perforated MH-W5 MH-W5W 12 132 VC Perforated MH-W5 MH-W6 18 290 VC Perforated MH-W6 MH-W6E 12 146 VC Perforated MH-W6 MH-W6W 12 132 VC Perforated MH-W6 MH-W7 18 302 VC Perforated MH-W7 MH-W7E 12 146 VC Perforated/CIPP MH-W7 MH-W7W 12 122.5 VC Perforated MH-W7 MH-W8 18 275.5 VC Perforated/CIPP MH-W8 MH-W8W 12 121.5 VC Perforated MH-W8 MH-W9 18 282.5 VC Perforated/CIPP MH-W9 MH-W9W 12 121.5 VC Perforated MH-W9 MH-W9S* 21 229 VC Perforated

MH-C1 MH-E1 12 440 VC Perforated X

MH-C1 MH-W1 12 440 CIPP X

MH-C1 MH-C2 12 320 VC Perforated X MH-C2 MH-C2E 12 209 VC Perforated MH-C2 MH-C2W 12 209 VC Perforated MH-C2 MH-C3 12 300 VC Perforated MH-C3 MH-C3E 12 182.5 VC Perforated MH-C3 MH-C3W 12 182.5 VC Perforated/CIPP MH-C3 MH-C4 15 300 VC Perforated MH-C4 MH-C4E 12 162.5 VC Perforated MH-C4 MH-C4W 12 162.5 VC Perforated MH-C4 MH-C5 15 310 VC Perforated MH-C5 MH-C5E 12 151 VC Perforated MH-C5 MH-C5W 12 151 VC Perforated/CIPP MH-C5 MH-C6 18 290 VC Perforated MH-C6 MH-C6E 12 146 VC Perforated MH-C6 MH-C6W 12 146 VC Perforated MH-C6 MH-C7 18 301 VC Perforated/CIPP MH-C7 MH-C7E 12 146 VC Perforated MH-C7 MH-C7W 12 146 VC Perforated/CIPP MH-C7 MH-C8 18 276 VC Perforated MH-C8 MH-E8 12 265 VC Perforated

From To Pipe Diameter (Inches)

Approx. Pipe Length (Feet) Pipe Type “Row 1”

MH-C8 MH-W8 12 265 VC Perforated MH-C8 MH-C9 18 283 VC Perforated/CIPP MH-C9 MH-E9 12 265 VC Perforated MH-C9 MH-W9 12 265 VC Perforated/CIPP

MH-E1 MH-ES 12 175 VC Perforated X MH-E1 MH-E2 12 285 VC Perforated X MH-E2 MH-E2E 12 220 VC Perforated MH-E2 MH-E2W 12 208 VC Perforated MH-E2 MH-E3 12 305 VC Perforated MH-E3 MH-E3E 12 182 VC Perforated MH-E3 MH-E3W 12 182.5 VC Perforated MH-E3 MH-E4 15 300 VC Perforated MH-E4 MH-E4E 12 151 VC Perforated MH-E4 MH-E4W 12 163 VC Perforated MH-E4 MH-E5 15 310 VC Perforated MH-E5 MH-E5E 12 132 VC Perforated MH-E5 MH-E5W 12 151 VC Perforated MH-E5 MH-E6 18 290 VC Perforated MH-E6 MH-E6E 12 132 VC Perforated MH-E6 MH-E6W 12 146 VC Perforated MH-E6 MH-E7 18 302 VC Perforated/CIPP MH-E7 MH-E7E 12 122.5 VC Perforated MH-E7 MH-E7W 12 146 VC Perforated MH-E7 MH-E8 18 275.5 VC Perforated MH-E8 MH-E8E 12 121.5 VC Perforated MH-E8 MH-E9 18 282.5 VC Perforated/CIPP MH-E9 MH-E9E 12 121.5 VC Perforated MH-E9 MH-E9S* 21 229 VC Perforated

Total Pipe Length to be Inspected 16,180 feet Task 1 – “Rows 2-9” Length 14,060 feet

Task 2 - “Row 1” Length 2,120 feet *Diagonal outfalls from manholes W9 and E9 cross beneath the tailwater; inspect down to the tailwater level.

1.2.2 Chute slab subdrains, Row 1 Subdrains

The Row 1 drainage pipes have several specific details relating to pipe inspections including:

• Leader pipes from the crest drainage and relief wells outfall into the Row 1 lateral pipe.

• The row 1 lateral pipes are anticipated to contain the greatest volumes of sediment observed in the subdrain system, with most of the sediment being drainage fill material (sand and gravel, aggregate sizes up to 3 inches). Without flushing, the sediment has previously proven to be a challenge for navigating a camera in the drains.

• As a result of the long-term movement of the spillway crest and slab, the row 1 drainage alignment is a low area behind the gates which ponds several inches of surface water. Additional coordination with the project office is required to access the five Row 1 manholes, which must be sandbagged to prevent inflow of surface water. Additionally, several of these manholes are no longer freely draining, and will need to be pumped to access the pipes.

1.2.3 Box Drains

The box drains are a square concrete conduit along the outside of each spillway chute wall which collect seepage through perforated vitrified clay plates. The box drain is accessible from manholes along the outside of the chute walls.

Table 2: Box Drain Segment Lengths

From To Pipe Diameter (Inches) Pipe Length (Feet) Pipe Type

EAST WALL

MH-1 MH-2 24 340 Concrete box drain MH-2 MH-3 24 295 Concrete box drain MH-3 MH-4 24 295 Concrete box drain MH-4 MH-5 24 295 Concrete box drain MH-5 MH-6 24 295 Concrete box drain MH-6 MH-13 24 210 Concrete box drain MH-13 MH-14 24 320 Concrete box drain MH-14 MH-15 24 205 Concrete box drain MH-15 MH-16 24 145 Concrete box drain

WEST WALL

MH-7 MH-8 24 340 Concrete box drain MH-8 MH-9 24 295 Concrete box drain MH-9 MH-10 24 295 Concrete box drain MH-10 MH-11 24 295 Concrete box drain MH-11 MH-12 24 295 Concrete box drain MH-12 MH-17 24 330 Concrete box drain MH-17 MH-18 24 250 Concrete box drain MH-18 MH-19 24 300 Concrete box drain

Total Pipe Length to be Inspected 4800 Feet

1.2.4 Crest Relief Wells

The crest structure relief wells are vertical drainage features with riser pipes accessible from the chute slab surface near the spillway crest. The wells also have short horizontal outfall segments which exit into the Row 1 lateral drainage pipe. The depth of the wells varies between roughly 30 and 60 ft. The well diameter varies, beginning as a 12” formed hole in the chute slab, transitioning to a 6” cast iron pipe through the subdrainage fill, then a 6” wood casing through the foundation, with a slotted segment in a specific reach for seepage collection.

Table 3: Crest Relief Wells Relief Well Location Depth (feet) SW 4 Monolith 4 ~30 SW 6 Monolith 6 32.9 SW 8 Monolith 8 34.6 SW 10 Monolith 10 39.5 SW 12 Monolith 12 41 SW 14 Monolith 14 43.4 SW 16 Monolith 16 ~48 SW 18 Monolith 18 ~35 SW 20 Monolith 20 ~32 SW 22 Monolith 22 ~32 SW 24 Monolith 24 32.3 SW 26 Monolith 26 ~32 SW 28 Monolith 28 58.2 SW 30 Monolith 30 ~55 Total: 550 feet

1.2.5 Powerplant Underseepage Drain Network

The powerplant under seepage drains provide drainage to the powerhouse area slopes and paved areas. This network includes catch basins with solid pipe segments for collecting surface runoff, and also perforated pipe segments for the purpose of collecting seepage from the dam foundation.

Table 4: Powerplant Drain Lengths From To Pipe diameter

(inches) Pipe length

(feet) Pipe type

Underseepage collection drainage lines, to MH17

MH11 MH12 12" 270

Slotted PVC (80 ft from MH11) / Perf V. C. (190 ft from MH12)

MH12 MH13 12" 85 Perf V. C.

OR29R MH29 8" 110 Stainless Steel Slotted Pipe OR29L MH 29 8" 50 Stainless Steel Slotted Pipe

MH29 MH13 12" 10 PVC

OR14R MH14 12" 125 Slotted PVC MH14 MH13 12" 170 Slotted PVC MH13 MH17 12" 135 Perf V. C.

MH25 MH17 30" 180 RCP

MH17 MH 18 36" 195 RCP

Underseepage collection drainage lines, to MH16 MH17 MH16 12" 150 Slotted PVC MH15 MH16 12" 100 Perf V. C.

MH28R MH 27R 12" 85 Solid PVC MH27R MH26R 12" 75 Solid PVC MH 26R MH16 12" 135 Slotted PVC

MH16 MH18 30" 155 RCP

Catch basin runoff drainage lines

CB10 MH25 12" 20 RCP

CB11 MH25 12" 75 RCP

CB21 MH25 12" 50 RCP

CB15 MH22 12" 30 RCP

CB17 MH22 12" 50 RCP

CB18 MH22 12" 50 RCP

CB19 MH22 12" 100 RCP

MH22 MH24 18" 160 RCP

CB13 MH23 12" 30 RCP

CB16 MH23 12" 30 RCP

MH23 MH24 12" 65 RCP

CB12 MH24 12" 30 RCP

CB14 MH24 12" 65 RCP

CB20 MH24 12" 110 RCP

MH24 MH25 24" 180 RCP

CB1 MH15 18" 245 RCP

CB2 MH17 12" 45 RCP

CB3 MH16 18" 20 RCP

Outfall area, catch basin lines

CB4 MH18 18" 115 RCP

CB8 MH18 12" 10 RCP

CB8 CB9 12" 85 RCP

CB4 CB5 12" 160 RCP

CB5 Upstream leg 12" 160 RCP

CB5 MH19 12" 20 RCP

CB5 CB6 12" 260 RCP

CB6 MH 20 12" 10 RCP

CB6 CB7 12" 250 RCP

CB7 MH21 12" 35 RCP

CB7 End section 12" 50 RCP

Outfall area, main collector pipe

MH18 MH19 36" 220 RCP

MH19 MH20 36" 220 RCP

MH20 MH 21 36" 265 RCP

MH 21 OUTFALL 36" 50 RCP

Total pipe length to be inspected 5,295 feet

Figure 3: Powerplant Under Seepage Drain Network

1.3 Site Access

Spillway Access. There are gravel roads connecting to Highway 200 that run along the chute on the East and West sides of the spillway chute (Figure 4). The spillway can be accessed via the ladders on the East and West sides of the spillway near the crest. Because of restricted access the spillway is designated as a confined space area. Access requires HEC clearance and daily lock-out tag-out sign on/off. Necessary permits and safety procedures need to be followed. The spillway slab is NOT accessible without signing onto a clearance at the powerplant. A minimum of 2 weeks notice must be given to Garrison Operations in advance of work to complete clearance paperwork.

Construction of an access stairway would eliminate the “limited or restricted access” resulting in the general spillway space no longer fitting the definition of confined space. HEC lock-out tag-out would still be applicable.

Manholes access. In order to enter the manholes in both the spillway and the powerplant parking lot, fall protection, ventilation, and air monitoring equipment will have to be used and provided by the Contractor. Manholes remain confined spaces regardless of the presence of an access staircase into the spillway. An activity hazard analysis (AHA) and accident prevention plan (APP), including fall protection plan and confined space plan, are required submittals for Government review prior to the execution of the work. See Sections 4.5.3 and 0 for additional information

Spillway Row 1 manholes. The row 1 manholes are in a low area which is inundated by shallow standing water.

Therefore, to access the manhole it must be ring-diked by sandbags. The water from inside the ring dike can then be bailed out to allow for access to the manhole without the influence of water from the surface of the spillway.

Powerplant drains. The powerplant underseepage drainage network can be accessed via the Garrison Dam powerplant parking lot. There is gated access with intercom connection to powerplant staff. The Contractor shall provide 2 weeks notice to Garrison Operations prior to executing work near the powerplant. Coordination with Garrison Operations is required prior to work to develop a plan for powerplant personnel parking to ensure no interference with the contractor’s work.

Figure 4: Spillway site access map

Figure 5. View of spillway crest from the west abutment.

Figure 6. View facing the west spillway wall from the east.

2. General Contract Information

2.1 Period of Performance

The Contractor shall complete all work within 225 calendar days from issuance of the award. The Contractor shall efficiently plan, coordinate, and execute work so that materials can be acquired and all activities completed within this duration. The breakdown of dates for individual submittals and milestones is presented in Table 5 (Section 4.1).

Fieldwork is not permitted within general winter conditions dates of Nov 1 to Apr 15 due to difficulty of accessing the work areas within these times.

2.2 Government Furnished Items and Services

The Contractor is to provide a minimum 2 weeks notice prior to mobilizing on site to allow for these preparations.

Any support required from Garrison Operations is only available between 0800 to 1500 on weekdays (Monday to Friday).

Items and support provided by the Government are to include:

a) Water Supply. A raw (non-potable) water fire hydrant is available at the Garrison project, outside maintenance shop located at the toe of the dam. Within the spillway area, water may be taken from the stilling basin and outlet channel if approved in the APP.

b) Sediment disposal area. Sediment collected from the drains shall be captured and properly disposed of so as not to impact Waters of the United States. The disposal site is accessible from the dam toe road as shown in Figure 1. It is located above the Ordinary High Water Mark.

c) Prior to the work, USACE will complete a maintenance cleaning of the spillway slab surface in the Row 1 area to reduce the volume of sediment which can obscure the manholes and relief wells locations.

Additionally, USACE will place markers indicating the location of the Row 1 manholes and relief wells.

d) Confined space and Hazardous Energy Controls (HEC) briefing and daily lock-out tag-out coordination for spillway chute access. The Contractor is to report to the Garrison Powerplant Operations Control Room prior to work each day. to sign on and at the end of each day to sign off (powerhouse is staffed 24 hours).

The Contractor shall provide their own locks for the clearance.

e) Equipment to open specific manholes at the powerhouse site (a handheld hook).

f) Welding. The relief well covers are currently welded shut. Assume that the welds will be removed prior to Contractor mobilization. The Government will re-weld these covers after Contractor de-mobilization. If any issues are encountered regarding welds on the relief well covers, contact the COR.

2.3 Contractor Furnished Items and Services

Except for the items specifically listed in Section 2.2 above, the Contractor shall furnish all supplies, equipment, facilities and services required to complete all tasks and meet all requirements presented in the PWS, with no additional assistance from the Government. For clarity, this includes:

a) Electrical / power. There is no electrical hook-up in the location of the camera inspections. The contractor shall supply all necessary power to the work area. If the Contractor elects to use a portable generator, KTR shall provide a spill containment plan (included in their EPP, see Section 4.5.5) to ensure no fuel enters any Government outfalls.

b) Equipment for access, fall protection and rescue, ventilation, and air monitoring for drainage manholes access.

c) Equipment and staffing to dewater the Row 1 manholes for access to the subdrain pipes.

d) Crane services for lowering equipment onto the spillway slab.

e) Typical tools for removing and re-installing manhole covers. Assume a variety of bolt sizes including 5/8”.

Re-fasten manhole covers with each bolt torqued to 20 ft-lbs. Replacement of the covers may require re-tapping threads.

f) Sandbags and sand or other means for isolating the Row 1 manhole covers from surrounding surface water.

2.4 Contractor POC’s

The Contractor shall, at a minimum, provide contact information for the project manager, the alternate project manager, and the lead field person working at the dam. Contact information shall include office phone, cell phone, and e-mail address for each individual. In addition, the contractor shall provide a 24-hour phone number that can be utilized to contact the contractor’s POCs outside of normal business hours. The Contractor will provide the updated contact lists anytime there is a change in personnel or contact information.

Project Manager. The Contractor shall assign a Project Manager (PM) to act as a primary point of contact (POC).

The PM shall be responsible for the coordination of the work developed under this Contract. Upon award of this task order, the Contractor shall immediately advise the Contracting Officer and COR in writing of the individual designated as such.

2.5 Government POC’s

The Contractor shall be in contact with multiple Government POCs representing the Army Corps of Engineers, Omaha District. The Contracting Officer (KO) is the only POC with authority to direct the Contractor to perform services. The Government POCs including COR, Technical lead, Technical Points-of-contact, QA staff, Project Manager, and Garrison project staff for this contract will be provided after contract award.

2.6 PWS Modifications

No person other than the Government Contracting Officer has the authority to make any changes to this contract action that impact cost or schedule. Authority from the Contracting Officer to the Contractor to make changes that impact cost or schedule will be in the form of an official, signed modification.

3. Description of Services

The contractor shall provide all personnel, equipment, supplies, facilities, transportation, tools, materials, supervision, and other items services necessary to assess/inspect the drains/collection systems as defined in this Performance Work Statement except for those items specified as government furnished property and services.

Remote operated camera equipment is required to document the existing condition of the systems. The contractor shall perform to the performance requirements and standards in this contract.

3.1 Task 1 - Flush, measure sediment, camera and report for Rows 2-9 spillway subdrain (14,060 ft) This work shall consist of flushing, measuring the sediment volume, camera-inspecting and reporting for all spillway slab subdrains accessed from Rows 2 through 9 manholes in the spillway chute slab. The subdrains of 12-18” I.D.

perforated vitrified clay pipe extend between individual manholes 6 to 12 feet depth below the spillway slab. The subdrains are located 0 to 3 feet above the manhole floor. Additional manhole and subdrain piping details are provided in Attachment 1. For all pipe inspections and reports the contractor will used the established naming convention for each manhole and pipe segment, provided in Table 1 for the chute subdrains.

Manhole Access and Dewatering. In Rows 2 through 9, it is anticipated that the manholes are sufficiently dry such that pumping is not required to access the subdrains. However, if pumping is necessary, document pre-existing water level and the pumping effort (rate, duration) utilized to achieve a dry condition for pipe inspections.

Manhole Observations. Prior to pumping, flushing, or other activities that would alter the existing condition of the pipe, document at each manhole a description the flow from pipes entering each manhole. For example, at MH-C5, a description may include simple qualitative flow descriptors, MH-C5 North - trickle, MH-C5 East - Dry, MH-C5 West - flowing. Current discharge rates from each subdrain is anticipated to be relatively small (less than 5 gpm). Base the flow description on these approximate flow rates: Dry (0 gpm), trickle (2-5 gpm), flow (>5 gpm). Note whether there is any change in the discharge from the pipes before/after the flushing (ie, change from “trickle” to “flow”, or “no change”.

Flushing and Sediment Measurement

• The Contractor’s Work Plan submittal will describe the intended cleaning equipment, flow rate, and water pressure, with care towards limitations for vitrified clay pipes as described in Section 4.4 and Table 6.

• Measuring the flushed sediment volumes is a requirement. The Contractor’s Work Plan submittal will describe the intended method to best capture and measure this sediment. Report sediment in units of volume, such as cubic feet. It shall be assumed that all pipes are approximately 20% filled with sediment and require hydro-flushing for complete and thorough inspection.

• Assume that Row 9 manholes have 1 ft depth of existing sediment (3 manholes * 1 ft depth * 4 ft width * 4 ft height = 48 cubic ft). Measure and remove this sediment prior to flushing any new sediment into the manholes. Assume Rows 2 through 8 manholes have negligible levels of existing sediment. USACE may provide sacks to preserve representative samples of the flushed gravel at select manholes.

• Collect two representative sack samples of the flushed drain material relating to this Task. For Task 1, at least one of these samples is to be collected from Row 9 lateral segments.

Pipe Camera Inspection. This work shall consist of remote camera inspection of all spillway slab subdrain segments. Section 4.4 provides more detailed specifications for the camera equipment and methods.

Reporting. Reporting will include the conditions and findings from the flushing, sediment measurement, and camera inspection. Section 4.4 provides more detailed specifications for the reporting requirements.

Performance Requirements. Section 4.4 and Table 7 “Performance Requirements Summary” summarize the primary criteria by which the success of the work will be evaluated, referencing the “Inspection Requirements for Remote Inspections” stated in USACE Engineer Manual 1110-2-2902. Criteria include the quality of cleaning, care of jetting pressure in clay pipes, camera capabilities and lighting, and completeness of reporting.

3.2 Task 2 – Flush, measure sediment, camera and report for Row 1 spillway subdrain (2,120 ft) This work shall consist of flushing, measuring the sediment volume, camera-inspecting and reporting for all spillway slab subdrains accessed from Row 1 manholes in the spillway chute slab. The subdrains of 12-18” I.D. perforated vitrified clay pipe extend between individual manholes 6 to 12 feet depth below the spillway slab. The subdrains are located 0 to 3 feet above the manhole floor. Additional manhole and subdrain piping details are provided in Attachment 1. For all pipe inspections and reports the contractor will used the established naming convention for each manhole and pipe segment, provided in Table 1 for the chute subdrains.

The Row 1 drainage system is separated from the broader subdrain system in the price schedule due to the additional steps required for access into the Row 1 Manholes, the anticipated greater volume of sediment along the Row 1 pipes, and the presence of relief well and crest leader pipes into the Row 1 drains to inspect. For purpose of this drainage inspection, Row 1 drain segments are defined as all segments attached to a Row 1 manhole and includes outfall segments MH-W1 to MH-W2, MH-C1 to MH-C2, and MH-E1 to MH-C2.

All steps and requirements for Task 1 (Subdrain Rows 2-9) also apply to Task 2 (Row 1), with additional details for Task 2 described below.

Row 1, Manhole Access and Dewatering.

• To prevent inflow of surface water and sediment into the manhole, place a sandbag ring or other means to isolate the manhole from the standing water. It takes approximately 12 sandbags to surround the manhole and provide some working area.

• It will be necessary for the Contractor to pump standing water within the Row 1 manholes to obtain access and camera-inspect in dry conditions. Document the depth to the water level from the top of the concrete spillway slab. Document the pumping rates and durations required to dewater the manhole, and to maintain dry conditions if continuous pumping is required. Assume there is approximately 5 ft of standing water in the manhole, and requiring 4 pumps of 2” diameter to accomplish the dewatering.

• Assume that Row 1 manholes have 1 ft depth of existing sediment (5 manholes * 1 ft depth * 4 ft width * 4 ft height = 80 cubic ft). Measure and remove this sediment prior to flushing any new sediment into the manholes.

Flushing and Sediment Measurement

• It shall be assumed that all pipes are approximately 40% filled with sediment and require hydro-flushing for complete and thorough inspection. See PWS Attachment 1 for additional photos of the Row 1 existing conditions.

Row 1, Pipe Inspection

• Note the leader pipes from both the crest drainage and from relief wells. There are 14 relief well header pipes (numbered from SW-4 to SW-30, even numbers only) and 28 crest leader pipes (numbered L-1 through L-28) which outfall into Row 1 piping.

• At each junction of these connections to the Row 1 drain, the device will stop, the camera will pan to the connection, and a short video will be taken to evaluate if there is flow from these pipes into the Row 1 drain.

Performance Requirements. Section 4.4 and Table 7 “Performance Requirements Summary” summarize the primary criteria by which the success of the work will be evaluated, referencing the “Inspection Requirements for Remote Inspections” stated in USACE Engineer Manual 1110-2-2902. Criteria include the quality of cleaning, care of jetting pressure in clay pipes, camera capabilities and lighting, and completeness of reporting.

3.3 Task 3 – Flush, measure sediment, camera and report for spillway box drains (4,800 feet) This work shall consist of flushing, measuring the sediment volume, camera-inspecting and reporting for all box drains located along the outer base of the spillway chute walls. Each box drain consists of a 24” I.D. square concrete pipe and is located within individual manholes that extend 20 to 25 feet below ground surface. Each box drain discharges outside the spillway stilling basin above the tailwater level. Discharge rates from each box drain are relatively small (less than 10 gpm). For all pipe inspections and reports the contractor will used the established naming convention for each manhole and pipe segment, provided in Table 2 for the chute box drains.

Manhole Access and Dewatering. The box drain access covers are located along the outside of the chute and can be reached by vehicle. It is anticipated that the box drain manholes are sufficiently dry such that pumping is not required to access the drains. However, if pumping is necessary, document the pre-existing water level and the pumping effort (rate, duration) utilized to achieve a dry condition for pipe inspections.

Manhole Observations. Prior to pumping, flushing, or other activities that would alter the existing condition of the pipe, document at each manhole a description the flow from the pipe segment above. Utilize the descriptors “Dry” (0 gpm), “trickle” (2-5 gpm), and “flow” (>5 gpm).

Flushing and Sediment Measurement. The Contractor’s Work Plan submittal will describe the intended cleaning equipment, flow rate, and water pressure, with care towards limitations for vitrified clay pipes as described in Section 4.4 and Table 6. While the box drain is primarily concrete pipe, there are spaced perforated vitrified clay pipe plates for collection of drainage from the chute wall backfill. The Contractor’s Work Plan submittal will describe the intended method to best capture and measure flushed sediment. Note any change in the discharge from the pipes before/after the flushing. It shall be assumed that all pipes are approximately 20% filled with sediment and require hydro-flushing for complete and thorough inspection.

Pipe Camera Inspection. This work shall consist of remote camera inspection of all box drain segments. Section 4.4 provides more detailed specifications for the camera equipment and methods. For the box drains, turn the camera to observe the condition of each vitrified clay pipe plate.

Reporting. Reporting will include the conditions and findings from the flushing, sediment measurement, and camera inspection. Section 4.4 provides more detailed specifications for the reporting requirements.

Performance Requirements. Section 4.4 and Table 7 “Performance Requirements Summary” summarize the primary criteria by which the success of the work will be evaluated, referencing the “Inspection Requirements for Remote Inspections” stated in USACE Engineer Manual 1110-2-2902. Criteria include the quality of cleaning, care of jetting pressure in clay pipes, camera capabilities and lighting, and completeness of reporting.

3.4 Task 4 – Sounding, camera and report for crest relief wells This work shall consist of depth-sounding, camera-inspecting and reporting of the 14 spillway crest relief wells.

Camera inspection should consist of at minimum a video inspection, by a device suitable/specific to the inspection of wells, that documents the condition of the riser, screen, and base of each relief well. The contractor shall provide video inspection reports that document notable features along with typical conditions with annotated depths from a stated reference point.

For all pipe inspections and reports the contractor will used the established naming convention for each manhole and pipe segment, provided in Table 3 for the crest relief wells.

Sequencing. Dewatering and inspection of the relief wells is to occur after the Row 1 manholes and drain segment have separately been flushed and inspected.

Covers Access and Dewatering. To prevent inflow of surface water and sediment into the manhole, place a sandbag ring or other means to isolate the manhole from the standing water. Sound and record the depth to base of well or top of sediment. If the sounded depth indicates that the well screens have collapsed or substantially filled with sediment, notify the COR. To facilitate camera inspection in dry conditions, pump the standing water from within the relief wells with a low-capacity pump, such that there is no risk of collapsing the pipe by pumping vacuum.

Camera Inspection and Reporting. Camera inspection and documentation requirements specific to the vertical relief wells include:

• Condition of relief well screens (encrustation, deposition, damaged screen, etc.).

• Locations of seepage inflow into the relief well screens.

• Estimation of percent relief well screen is damaged, encrusted, plugged, etc..

• Condition of relief well riser pipes and joints including riser cap/cover as appropriate (structural damage, mechanical, corrosion, etc.)

• Continuous depth measurement from top of riser or manhole. The zero reference point shall be recorded at the time of the inspection and provided in the written documentation.

• A table indicating the depth to the outfall pipe invert, top of screen, bottom of screen, top of sediment/deposition (as applicable), bottom of relief well and any areas of concern/damage.

Performance Requirements. Section 4.4 and Table 7 “Performance Requirements Summary” summarize the primary criteria by which the success of the work will be evaluated, referencing the “Inspection Requirements for Remote Inspections” stated in USACE Engineer Manual 1110-2-2902. Criteria include the camera capabilities and lighting, and completeness of reporting.

3.5 Task 5 – Temporary Chute Access Staircase

Construct a temporary staircase for ease of access into the chute for both the Contractor and USACE staff. The intent of the staircase is to provide improved site access relative to the existing ladder. Construction of an access stairway would eliminate the “limited or restricted access” resulting in the general spillway space no longer fitting the definition of confined space. HEC lock-out tag-out would still be applicable. Construction of the staircase can be sub-contracted. Meet all OSHA regulations and requirements of USACE EM 385-1-1, Safety and Occupational Health (SOH) Requirements.

3.6 Task 6 - All Other Work

This work shall include costs associated with mobilization and de-mobilization of personnel and equipment, pre-fieldwork submittals, pre-fieldwork meetings, weekly fieldwork meetings, and fulfillment of any requirements presented in Section 2 “General Contract Information” and Section 4 “Contractor Requirements” that are not associated with any other specific tasks. Review the Submittal Register (Table 5) for a list of pre-fieldwork submittals. Table 7 “Performance Requirements Summary” summarizes the primary criteria by which the success of the work will be evaluated.

3.7 Task 7 (Option 1) – Flush, measure sediment, camera and report for power plant drainage (5,295 feet) This work shall consist of flushing, measuring the sediment volume, camera-inspecting and reporting for 5,295 linear feet of the power plant seepage drain network located at the power plant parking lot. The drainage system includes a combination of manholes and catch basins. The depth of manholes is comparable to within the spillway slab. For all pipe inspections and reports the contractor will used the established naming convention for each manhole and pipe segment, provided in Table 4 for the powerhouse drainage.

Manhole Access. See PWS Attachment 1 for a map of the powerhouse drainage network and measured flow rates. The drainage network can be roughly divided into two halves, with one half draining towards MH16 and the other half to MH17. Individual upstream drain segments may individually collect 10-20 gpm, with MH16 regularly receiving cumulative 50 gpm and MH17 at 75 gpm. Both of these manholes connect to a 36” RCP outfall system beginning at MH18. Given these inflows, access to drainage pipes may require pumping and diversion of drainage flows. Document pre-existing water level and the pumping effort (rate, duration) utilized to achieve a dry condition for pipe inspections.

Manhole Observations. Prior to pumping, flushing, or other activities that would alter the existing condition of the pipe, document at each manhole a description the flow from the pipe segment above. For the powerhouse, use the descriptors “dry” (0 gpm), “light flow” (<10 gpm), “flow” (10 gpm).

Flushing and Sediment Measurement. The Contractor’s Work Plan submittal will describe the intended cleaning equipment, flow rate, and water pressure, with care towards limitations for vitrified clay pipes as described in Section 4.4 and Table 6. The Contractor’s Work Plan submittal will describe the intended method to best capture and measure flushed sediment. Note any change in the discharge from the pipes before/after the flushing. It shall be assumed that all pipes are approximately 20% filled with sediment and require hydro-flushing for complete and thorough inspection.

Pipe Camera Inspection. This work shall consist of remote camera inspection of all powerhouse drainage segments.

Section 4.4 provides more detailed specifications for the camera equipment and methods.

Reporting. Reporting will include the conditions and findings from the flushing, sediment measurement, and camera inspection. Section 4.4 provides more detailed specifications for the reporting requirements.

Performance Requirements. Section 4.4 and Table 7 “Performance Requirements Summary” summarize the primary criteria by which the success of the work will be evaluated, referencing the “Inspection Requirements for Remote Inspections” stated in USACE Engineer Manual 1110-2-2902. Criteria include the quality of cleaning, care of jetting pressure in clay pipes, camera capabilities and lighting, and completeness of reporting.

4. Contractor Requirements

4.1 Submittal Register and Schedule

Government quality assurance review and approval is required for all submittals. Unless otherwise noted, allow for 15 calendar days for Government review of submittals. Rejected submittals shall be resubmitted for approval. The approval of submittals shall not be construed as a complete check and will not relieve the Contractor of the responsibility of quality control and providing satisfactory services in accordance with this PWS.

4.1.1 Submittal list and schedule

See table and sections below for more details about required submittals.

Table 5: Submittal Register Submittal Type Submittal Name Schedule PWS

Ref Pre-Field Work Submittals Included in Task 6 – All Other Work Pre-work meeting minutes – contract kickoff 7 days after award 4.3 Work Plan / Quality control plan 14 days after award 4.2 Site safety and health officer 14 days after award 4.5.2 Activity Hazard Analysis (AHA) 14 days after award 4.5.3 Accident prevention plan (APP) including:

fall protection plan, confined space plan, crane lift plan

14 days after award 0

Environmental Protection Plan (EPP) 14 days after award 4.5.5 E-verify and security documentation 30 days after award 4.6.4 Pre-work meeting minutes – pre-mobilization 30 days after award 4.3 Pre-work meeting minutes – on-site kickoff 45 days after award 4.3 Milestone Fieldwork kickoff 45 days after award - In-Progress Submittals Included in Task 6 – All Other Work Weekly progress meeting minutes - 4.3 Milestone All fieldwork complete 105 days after award* - Final Submittals Included in Inspection Tasks 1, 2, 3, 4 ,7 Draft camera inspection report 135 days after award* 4.4 Final camera inspection report 165 days after award* 4.4 Milestone All work complete 195 days after award*

*Up to 30 additional days if including Task 7 (Option 1) – resulting in fieldwork complete at 135 days and contract duration at 225 days.

4.1.2 Submittal form

Submittal form ENG Form 4025-R shall be used for transmitting the submittal. This form may be reproduced by the Contractor and shall be properly executed by filling out all the heading blank spaces and identifying each time submitted. Special care should be exercised to ensure proper listing of the specification paragraph or sheet number of the contract drawings pertinent to the date submitted for each item. The Contractor shall provide copies for each submittal to the locations stated below.

4.1.3 Means of approvals

Action Codes will be as indicated on the back of ENG Form 4025-R. The Contracting Officer’s Representative will mark an Action Code on each submitted ENG Form 4025 prior to returning a copy to the Contractor. The approval of a submittal by the Contracting Officer shall not be construed as a complete check but will indicate only that the general method of prosecution and detailing is satisfactory. Approval will not release the Contractor from responsibility for any error that may exist, as the Contractor is responsible for satisfactory prosecution and detailing of all work.

All submittals related to performance of work must be approved before work begins. No work can begin without approved submittals. If a submittal is E coded (disapproved), the KTR must address comments and resubmit to the Government for approval prior to work. Resubmittals also are allowed 20 days for review.

4.1.4 When not approved

Action Codes will be as indicated on the back of ENG Form 4025-R. The Contracting Officer’s Representative will mark an Action Code on each submitted ENG Form 4025 prior to returning a copy to the Contractor. The approval of a submittal by the Contracting Officer shall not be construed as a complete check but will indicate only that the general method of prosecution and detailing is satisfactory. Approval will not release the Contractor from responsibility for any error that may exist, as the Contractor is responsible for satisfactory prosecution and detailing of all work.

4.1.5 Submittal delivery contacts

The Contractor shall provide an electronic copy of ENG Form 4025-R with each submitted item to the COR and the Primary and Alternate Technical Points of Contacts listed in Section 8.0, Coordination.

4.1.6 Submittal delivery means

Provide the submittals listed in the subparagraphs below to the Government for review. Provide electronic deliverables for the submittal packages that are electronically bookmarked. Transmit deliverables to the Government using DoD SAFE (https://safe.apps.mil/). Physical hard drives may be required for individual files larger than 8 gigabytes (GB). Electronic files shall be in a complete and useable format by the Government. Provide the original electronic file types when requested by the Government and at the conclusion of this contract. All documents shall be fully compatible with software programs identified in the narrative below without any changes required of the Government.

Provide electronic files meeting the following requirements:

a) Meeting Minutes

a. Size: Letter, 8.5-inches by 11-inches.

b. File type: Microsoft Word.

c. Deliverable type: Portable Document File (PDF).

b) Reports

a. Size: Letter, 8.5-inches by 11-inches.

b. File type: Microsoft Word.

c. Deliverable type: Portable Document File (PDF) and Microsoft Word.

4.2 Work Plan, Quality Assurance and Control

The Contractor shall implement a comprehensive quality assurance/quality control (QA/QC) program to ensure that all work is conducted in accordance with the PWS and associated requirements. This program shall cover all aspects of work covered under this PWS to include field activities, data collection and reduction, and reports. The

Contractor’s Project Manager is responsible for the development and implementation of the QA/QC program. A QA/QC Plan will be included in the Work Plan as indicated below.

The Work Plan submittal is to include the Inspector Operator Qualifications, baseline schedule, description of cleaning and camera equipment; planned procedures for drainage access, safety, cleaning, and camera-inspection;

template reporting documents, and QA/QC plan for all aspects of work. Include specifically which equipment will be lowered into the spillway chute, how sediment will be removed from the manholes and delivered out of the spillway chute to the disposal location. The presentation of the schedule is to include a Gantt chart presenting development, submission, and review dates for submittals; kickoff and duration for specific field activities, and final submittals.

4.3 Pre-Work Meetings

The Contractor shall participate in three pre-work meetings for different phases of the project following award of the requirement and prior to commencement of major work activities to coordinate with the COR and Technical Points of Contact. The Contractor is required to submit meeting minutes for each meeting.

a) Contract kickoff meeting: Prior to commencing any activities, the Contractor shall participate in a virtual Kickoff Meeting. The COR will review contract requirements as part of the meeting. The Government will host the meeting and develop the agenda. The Contractor shall take and distribute meeting minutes for the kickoff. This meeting will cover topics including work requirements, scheduling, submittal process, and material procurement lead times. The Contract Kickoff meeting will be planned for four (4) hours.

b) Pre-mobilization meeting: This virtual meeting shall be conducted two weeks prior to mobilization to the site. This meeting ensures all necessary on-site coordination has been completed and include review of the pre-submittals. The Pre-Mobilization meeting will be planned for two (2) hours.

c) On-site kickoff meeting; Following mobilization and prior to the start of drilling, a formal on-site meeting will be held with Garrison Dam project staff and QA staff, the Contractor, and QC staff. The Government and Contractor shall review the QCP and plan for ongoing communications. Government and KTR will review status of all submittals to ensure they are approved before work begins during this meeting. KTR will present QCP/APP/EPP/schedule to the Government for full understanding of work. The Contractor shall document and distribute meeting minutes. The On-Site Kickoff meeting will be planned for two (2) hours.

d) (In-Progress Submittal) KTR shall schedule a weekly meeting with the Government COR to discuss project progress once work begins. KTR to send meeting minutes to the Government after each meeting.

4.4 Performance Requirements Summary

The Contractor service requirements are summarized into performance objectives that relate directly to mission essential items. The performance threshold briefly describes the minimum acceptable levels of service required for each requirement. These thresholds are critical to mission success.

To ensure the Government receives the services for which it contracted, the COR will only pay for services received. The Performance Requirements Summary (PRS) determines whether the Contractor meets the performance standards set forth in the PWS and lists guidelines for how and when surveillance will be performed. It ensures timeliness and effectiveness and ensures that the Contractor is delivering the results specified in the PWS and resulting contract. COR contract quality assurance will be performed per the PRS surveillance schedule. No partial payments will be authorized for work performed that does not meet PRS.

Surveillance. Periodic inspections by the COR will serve as the surveillance methods. If the COR discovers deficiencies or receives complaints, the COR will alert them on to the Contractor for correction.

Unacceptable Performance. When performance is determined unacceptable, as defined in the Performance Requirements Summary, the COR will inform the Contractor that performance is unacceptable and furnish written documentation by use of the Form DD 2772, Contract Discrepancy Report. By initialing and dating the form, the Contractor is only acknowledging notification of unacceptable performance. Disputes in surveillance should be referred to the Contracting Officer (KO).

The COR will notify the KO of less than acceptable performance. If any of the services do not conform to Contract requirements, the Government may require the Contractor to perform the services again in conformity with Contract requirements, at no increase in Contract amount. When the defect(s) in services cannot be corrected by re-performance, the Government may:

• Require the Contractor to take necessary action to ensure future performance conforms to Contract requirements.

• Reduce the Contract price to reflect the reduced value of the services performed.

• If the Contractor fails to promptly re-perform the services, or to take the necessary action to ensure future performance in conformity with Contract requirements, the Government may take corrective actions to mitigate risk to the government.

Requirements for Remote Inspections and Documentation

Inspection Requirements for Remote Inspections stated in EM 1110-2-2902 - 6.6.2.

• 6.6.2.1 - Inspector Operator Qualifications o The Operator is familiar with the system and the features to be inspected ahead of time so in the field key points to check are already known. For example, the KTR should be familiar with the anticipated distance from a given MH that a Relief Well inlet will be encountered, so these features are not accidentally overlooked.

o The individual performing the inspection is required to demonstrate their qualifications by providing training and experience records. Individuals operating the remote inspection equipment must be trained and certified by the NASSCO PACP, or an organization with equivalent standards.