31_09_13.pdf

Isabella Lake DSMP - Dams and Spillways 1966 April 21, 2017

SECTION TABLE OF CONTENTS

DIVISION 31 - EARTHWORK

SECTION 31 09 13

GEOTECHNICAL INSTRUMENTATION AND MONITORING

PART 1 GENERAL

1.1 SUMMARY

1.1.1 Geotechnical Instrumentation

1.2 REFERENCES

1.3 DEFINITIONS

1.3.1 Vibrating Wire Piezometer (VW Piezometer)

1.3.2 Survey Measurement Points

1.3.3 Accelerograph

1.3.4 Open tube well.

1.3.5 Staff gage

1.3.6 Flume

1.3.7 Flow meter

1.3.8 Hour meter

1.3.9 MEMS Tiltmeter

1.3.10 Surge Protectors

1.3.11 Grounding System

1.3.12 Portable Readout Box

1.3.13 Automated Data Acquisition System

1.3.14 Guide Posts And Survey Measurement Point Station Markers

1.3.15 Restricted Pool

1.4 SUBMITTALS

1.5 QUALIFICATIONS

1.6 REQUIREMENTS

1.7 PROJECT/SITE CONDITIONS

1.8 DETAILED DRAWINGS

PART 2 PRODUCTS

2.1 GENERAL

2.1.1 Manufacturer's Product Data

2.1.2 Operation and Maintenance (O&M) Manual

2.2 COMPONENTS

2.2.1 Open Tube Piezometers

2.2.2 Vibrating Wire Piezometers

2.2.3 Survey Measurement Points and Survey Control Points

2.2.3.1 New Station Markers

2.2.3.2 Survey Measurement Point Markers

2.2.3.3 Guide Posts

2.2.4 Strong Motion Accelerographs

2.2.4.1 Outside Accelerograph Housing and Installation

2.2.4.2 Main Dam Tower Accelerograph and MEMS Tiltmeter housings

2.2.5 Staff Gage

2.2.6 Hour Meter

2.2.7 Two Inch Parshall Flumes at Main and Auxiliary Dam

2.2.8 MEMS TiltMeters

31 09 13 - 1 Amendment 0004

2.2.9 Cables

2.2.10 Grounding System

2.2.11 Surge Protection

2.2.11.1 Conduits, power, and communication

PART 3 EXECUTION

3.1 EXAMINATION

3.1.1 Access

3.1.2 Instruments And Installations

3.2 PREPARATION

3.2.1 Protection

3.3 INSTALLATION

3.3.1 Instruments

3.4 MONITORING

3.4.1 Survey Measurment Point Monitoring

3.4.2 Accelerographs, Seismic Alarm Device, and MEMS Tiltmeters

3.5 TESTS, INSPECTIONS, AND VERIFICATIONS

3.6 MANUFACTURER'S FIELD REPORTS

3.7 TEST REQUIREMENTS

3.7.1 Tests

3.7.2 Inspections

3.8 FINAL DRAWINGS

3.9 OPERATION AND MAINTENANCE (O&M) MANUAL

-- End of Section Table of Contents --

31 09 13 - 2

SECTION 31 09 13

GEOTECHNICAL INSTRUMENTATION AND MONITORING

PART 1 GENERAL

1.1 SUMMARY

This Specification section covers geotechnical instrumentation for monitoring the performance of the Isabella project.

1.1.1 Geotechnical Instrumentation

The instrumentation includes new instruments as well as existing Government instruments that are to be preserved during construction. Read existing instrumentations daily for pool elevations below Restricted Pool and twice a day for pool elevations above Restricted Pool. Make all instruments available for readings during construction. Some existing instruments will be abandoned per Section 33 29 13 EXPLORATION AND PIEZOMETER HOLE ABANDONMENT. Concrete manhole specifications are covered under Section 33 40 00 STORM DRAINAGE UTILITIES and the drawings. Refer to the drawings for the location and list of existing instruments to be abandoned or preserved and the list of new instruments. [Geokon manufacturer is specified here, but other manufactures such as Roctest, Campbell Scientific, RST, and Sutron may be acceptable if approved]. The entire instrumentation system, including seismographs, vibrating wire floats, vibrating wire piezometers, Micro Electro Mechanical Systems (MEMS) Tiltmeter, and associated dataloggers must be compatible and communicative. This is to resolve compatibility issues.

1.2 REFERENCES

The publications listed below form a part of this section to the extent referenced. The publications are referred to within the text by the basic designation only.

ASTM INTERNATIONAL (ASTM)

IEEE Std 142 (2007) Recommended Practice for Grounding of Industrial and Commercial Power Systems

- IEEE Green Book (Color Book Series)

U.S. ARMY CORPS OF ENGINEERS (USACE)

EM 385-1-1 (2014) Safety and Health Requirements Manual

EM 1110-1-1002 (2012) Survey Markers and Monumentation

EP 310-1-6a (2006) Sign Standards Manual, VOL 1

1.3 DEFINITIONS

The following is a description of terms and acronyms that are common to the instrumentation work:

31 09 13 - 3

1.3.1 Vibrating Wire Piezometer (VW Piezometer)

Electric vibrating wire Piezometer to measure water pressure in the dam embankment and foundation. This will be installed in an open tube well.

1.3.2 Survey Measurement Points

Surface mounted survey points installed to monitor potential movement.

Horizontal and vertical surveys are conducted using a combination of conventional optical surveys, light detection and ranging (LiDAR) or global positioning systems (GPS) methods.

1.3.3 Accelerograph

A self-contained electronic system that senses acceleration and records signals higher than a preset threshold for later recovery. The electronic system is housed in a sealed housing that is fastened to a solid base. The Accelerograph operates on 12 volt DC power provided by direct power supply with a backup grid charged battery. The accelerographs will be housed in a special enclosure at the locations shown on the drawings.

1.3.4 Open tube well.

A drill hole in the ground, sleeved with a pipe, influence zone, and cap that allows transmission of pore water pressure through the influence zone and up the standpipe. This measures groundwater levels. Vibrating wire piezometers are instruments placed in the well to measure the groundwater level.

1.3.5 Staff gage

Staff gage provides for measurement of depth of water at the stilling basin downstream of the Main Dam to NAVD88 elevation.

1.3.6 Flume

Flume is an overflow structure to measure the rate of flow of water based on staff gauge readings.

1.3.7 Flow meter

Flow meter monitors the amount of water being pumped.

1.3.8 Hour meter

Hour meter measures the duration that the pump is in operation.

1.3.9 MEMS Tiltmeter

Electric MEMS tiltmeter to measured the vertical tilt of the Main Dam Control Tower at two biaxial axis. The biaxial tiltmeter will be installed at three locations: the operation flood level, soil structure interface, and top of the tower.

1.3.10 Surge Protectors

Specially designed electronic components mounted on a printed circuit board and connected directly to electrical instrument leads at the first point of exit from the subsurface. The surge protectors detect transient electrical

31 09 13 - 4 currents in the sensor leads and short the currents directly to a ground system.

1.3.11 Grounding System

A system of copper cables and ground contacts to establish a positive path to the earth for transient electrical currents. The grounding system requirements will be determined at each location. Grounding systems are to be local, dedicated systems. Grounding of several separated locations to different ground points is not allowed since this produces ground loops that can transmit electrical transients.

1.3.12 Portable Readout Box

The manual readout box for use with MEMS Tiltmeter and vibrating wire piezometers. The readout box can store readings and can later be transmitted to a computer and imported into spreadsheet and database applications.

1.3.13 Automated Data Acquisition System

ADAS is described in Section 31 09 13.11 AUTOMATED DATA ACQUISITION SYSTEM.

1.3.14 Guide Posts And Survey Measurement Point Station Markers

Posts, signs, and markers to designate the location of flush mounted items, stationing, and indicate possible embankment movement.

1.3.15 Restricted Pool

Restricted Pool is the Isabella Lake reservoir pool at Elevation 2589.26 feet, NAVD88.

1.4 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for information only. "DO" stands for District Office. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. Submit all submittals for approval at least 35 days prior to installation. Submit the following in accordance with Section 01 33 00

SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Accelerograph Housing Locations and Power Plan; G, DO

Existing Instrumentation Preservation Plan; G, DO

Resume Of The Instrumentation Specialist; G, DO

Pre-Installation Test Of The Instruments; G, DO

SD-02 Shop Drawings

Detailed Drawings; G, DO

SD-03 Product Data

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List of proposed products; G, DO

Manufacturer's Product Data

Manufacturer's Calibration Sheet

SD-06 Test Reports

Field Monitoring Report; G, DO

Pre-installation Test Reports; G, DO

Video Inspect New And Existing Open Tube Piezometer Instruments;

G, DO

Daily Instrumentation Report; G, DO

SD-07 Certificates

Manufacturer's Qualifications; G, DO

List of proposed subcontractors; G, DO

Manufacturer's Calibration Data Sheets; G, DO

SD-08 Manufacturer's Instructions

Installation procedures and details

SD-09 Manufacturer's Field Reports

Manufacturer's Field Reports

SD-10 Operation and Maintenance Data

Operation and Maintenance (O&M) Manual

SD-11 Closeout Submittals

Final Drawings; G, DO

Manufacturer's Warranty

Contractor's Warranty for Installation

Initial Reference Surveys

Operation and Maintenance (O&M) Manual; G, DO

1.5 QUALIFICATIONS

Submit a list of candidate Manufacturer's Qualifications who can demonstrate the ability to supply the required instrumentation for approval by the Contracting Officer.

a. The manufacturer to supply the specified instruments must be a company specializing in the manufacturing of these specific types of instruments with a minimum of ten years of documented experience. The manufacturer must demonstrate the ability to supply the specified

31 09 13 - 6 instrumentation in the required quantities according to the project schedule.

b. Provide an Instrumentation Specialist with at least ten years of experience installing all instruments/types such as those specified herein. Submit resume of the Instrumentation Specialist for approval.

Submit resumes of all instrumentation personnel who will be handling, installing, and reading of instruments for approval. Instrumentation Specialist substitution will not be allowed without prior written approval. This applies to all electronic instrumentation installation and open tube piezometer installations.

1.6 REQUIREMENTS

a. Provide the instrumentation at the main dam and auxiliary dam embankments, including vibrating wire piezometers, accelerographs, MEMS TiltMeter, staff gage, hour meter, flow meter, survey measurement points, Parshall Flumes, open tube piezometers, portable readout devices required for manual operations, and connections and/or terminations of the instrumentations to the appropriate readout panels and the Automated Data Acquisition System (ADAS) described in Section

31 09 13.11 AUTOMATED DATA ACQUISITION SYSTEM.

b. A California Licensed Land Surveyor must perform reference surveys of all the survey measurment points required on the Drawings and specifications and survey all instrument locations as installed. The survey must be done pre construction and post construction. Results of the reference surveys must be provided to the Contracting Officer for review as part of the Closeout Submittals. The survey datum must be NAVD 1988 and NAD 1983.

c. Drilling of new instruments in the embankment or foundation must follow Section 31 09 15 EARTH EMBANKMENT AND EARTH FOUNDATION DRILLING

REQUIREMENTS.

1.7 PROJECT/SITE CONDITIONS

The geotechnical instrumentation shown and described is based on currently available information. Conditions encountered during construction may require additions or deletions.

1.8 DETAILED DRAWINGS

Submit detailed drawings for approval by the Contracting Officer. The working Drawing must show all details, dimensions, specific instruments, materials, and any other details necessary to produce an installation that meets the requirements in the drawings and specifications.

PART 2 PRODUCTS

2.1 GENERAL

Submit a list of proposed products including instruments with the full required cable lengths. Where model numbers are given in this section, they represent models selected on the basis of past factory specifications and project experience demonstrating that the equipment, including stipulations herein, will meet the performance objectives of this work.

Verify with any selected manufacturer that the designated model, or the updated version, or approved equivalent, meets the design performance

31 09 13 - 7 outlined by these specifications.

2.1.1 Manufacturer's Product Data

Submit Catalog cut sheets and manuals, list of proposed products, ,detailed drawings, manufacturer's calibration data sheets, manufacturer's field reports, pre-installation test reports, (including recommended spare parts list) for all instrumentation. Provide complete and legible catalog cut sheets, product data, installation instructions, operation and maintenance instructions, warranty, and certifications for products and equipment for which final material and equipment choices have been made. Indicate, by prominent notation, each product that is being submitted including optional manufacturer's features, and indicate where the product data shows compliance with the Contract requirements.

2.1.2 Operation and Maintenance (O&M) Manual

Submit Operation and Maintenance (O&M) Manual as supplied by the instrument manufacturer for the installed instruments.

2.2 COMPONENTS

2.2.1 Open Tube Piezometers

a. New Instruments: See drawings for locations, depth, and details for new instruments. Provide all materials for constructing 2-inch internal diameter open tube piezometers. The screen and casing must be schedule 80 PVC pipe or better, flush coupled PVC. The screen must be five feet to ten feet in length (see drawings) with three rows of 0.01 inch wide slots equally spaced around pipe, slot lengths as required to leave

0.25 inch between rows, longitudinally spacing of slots within a row of 62 slots per linear foot. The tube must be furnished with plug in bottom, reducing bushing in top, preassembled by manufacturer. Provide 1/4 inch bentonite pellets and zone 2A filter sand and ASTM C33 #67 coarse aggregate (3/4" minus), for installation as shown on the drawings.

b. For new instruments: Place and compact a 1 foot depth of saturated zone 2A filter in the hole below the piezometer tip prior to placing the slotted pipe and riser pipe. After piezometer has been placed in the hole, place and compact sand (granular filter) all the way around the piezometer and up above the top of the slotted pipe (screened) influence zone. Place the bentonite seal above the sand pack. Use the bentonite seal within 5 feet of Zone 2A filter sand, Zone 2B drain rock, and Zone 3 Transition material. Bentonite seal must be 1/4" bentonite pellets. The bentonite seal must be at least 5 feet thick as measured immediately after placement without allowance for swelling.

Directly measure and record the final depth to the top of the bentonite seal. Do not estimate the final depths. If bentonite seal is placed in a dry zone, add water to the bentonite for proper hydration. In this condition, place the bentonite seal in 1 foot lifts with each lift hydrated for a period of 30 minutes. The elevation of the slotted pipe (screen) is approximate and the final location will be determined by the Contracting Officer after the borehole is drilled and the borehole log has been examined. Final location of the slotted pipe (screen) will be based on the soil materials and layering encountered from the borehole.

c. Existing instruments: Preserve existing piezometers shown on the

31 09 13 - 8 drawings. Protect and read these piezometers during construction.

These instruments must be available and accessible for data collection during construction by the Government. Extend these instruments with the new embankment. Replace damaged piezometers at Contractor's expense within 2 weeks of destruction. Damage includes cracking, shearing, blockage from material, or any other physical prevention of reading the piezometric influence zone or effective readings values.

Existing instruments must be finished with the same protective housing as the new instruments. Each housing must have a plastic engraved plaque installed on the side of the housing. The plaque must be a minimum dimension of 2-inch by 4-inch, with the correct instrument name engraved on it in white, minimum font size of 12, with a dark background.

d. Provide protective housing for the open tube piezometers with hinged locking cap and padlock. Protect, automate, and read existing instruments during construction. Also, make the open tube piezometers continuously available for Government inspection or reading by the Government. Keys for the locks must be provided to the Government during construction. Each housing must have a plastic engraved plaque installed on the side of the housing. The plaque must be a minimum dimension of 2 inch by 4 inches, with the correct instrument name engraved on it in white, minimum font size of 12, with a dark background.

e. The final finished housing must be 18 inch internal diameter galvanized schedule 40 Steel pipe, installed to have a minimum of 2 foot extension from the finished ground surface as shown on the drawings. The piezometer must have an 8 inch internal diameter schedule 80 PVC protective riser installed around it, with a 3.5-foot by 3.5-foot concrete slab around the 18 inch diameter steel pipe protective casing as shown on the drawings. The top of the housing must be hinged and lockable, with a watertight port for wireless connectivity of the ADAS automated system. See drawings.

2.2.2 Vibrating Wire Piezometers

a. Provide new vibrating wire (VW) piezometers in all piezometers and flumes. Test and verify that the VW piezometers are functional. Test and verification procedure as recommended by the manufacturer.

b. Vibrating wire piezometers must be sealed (non-vented) stainless steel or titanium-bodied cylindrical sensors with an internal welded bulkhead seal in addition to the seal at the cable jacket exiting the transducer housing. The sensors must include a low air entry stainless steel filter tip to prevent fines migration into the diaphragm area. The transducers must have a thermistor included in the sensor body to measure temperature. The vibrating wire piezometers must be models 4500 ALV as manufactured by Geokon Inc., Lebanon, NH or approved equivalent.

c. Provide vibrating wire piezometers with pressure range of at least 700 kpa or 100 psi at the locations shown on the drawings.

d. Provide sufficient cable length required for ADAS connection with an additional 10 feet of cable at finished grade. The cables must be shielded. Field splices are not allowed in wet or damp conditions.

This includes all open tube piezometers and flumes.

31 09 13 - 9

e. Provide two vibrating wire portable readout boxes from the same manufacturer as the vibrating wire piezometers and MEMS tiltmeters and 2 vibrating wire analyzers. Provide these devices for testing and quality control purposes. The portable readout box must be capable of reading a variety of vibrating wire sensors, including the pressure transducers (vibrating wire piezometers), MEMS tiltmeters, and storing manually collected readings in memory for later recovery. The portable readout box must be Field PC, Model FPC-2 manufactured by Geokon, Incorporated with all necessary accesseries or approved handheld equivalents that can read Vibrating Wires and MEMS Titltmeters instrumentation are acceptable. The vibrating wire analyzer must be Campbell Scientific's VwAnalyzer, as manufactured by Campbell Scientific, Logan Utah. All readouts and analyzers must be set up to read all applicable instruments in feet, NAVD88 datum, and with a time-plot graph of readings.

f. Keep six extra vibrating wire piezometers, lightning arrestor cards, and communication devices onsite in reserve. If a vibrating wire piezometer is destroyed or taken out by lightening, replace it with a tested and verified vibrating piezometer wire setup within the next 3 days.

2.2.3 Survey Measurement Points and Survey Control Points

a. Provide all materials for constructing the surface mounted survey points as shown on the drawings. Survey control points must be Type G monuments. Survey Measurement points must be 1 inch stainless steel rebar with a punch mark on center.

b. Survey Control Points: Set survey control points in soil, rock, or existing concrete on either end of the dam. Install the survey control points in a minimum 16-inch diameter by 36 inch deep, concrete filled hole. Drive or drill the 5/8 inch (#5) stainless steel rebar 5 feet into the fill or rock. If installed at the edge of the road, replace asphalt to make a smooth surface for all points. The Contracting Officer will determine the final placement of the control points with the contractor. Control Points must be in line with the measurement points.

The control points must be standard USACE survey disk with the label shown on the drawings. The survey control points must conform to Type G monument per EM 1110-1-1002, or better.

c. Survey Measurement Points: Drive or drill and drive 1 inch stainless steel rebar 5 feet into the ground or rock surface, and concreted down 3 feet, minimum 16 inch diameter around the measurement point. The finished grade of the rebar and concrete must be at the finished grade level. Install the survey points as shown on the drawings. Install in locations shown on the drawings and as directed by the Contracting Officer.

Align the crest survey measurement points just downstream from the guide posts as to not interfere with the posts. Install the Main Dam Instrumentation Bench measurement points on the downstream side of the bench , along the bench , not on the slope of the dam. After installation, perform an Initial Reference Surveys of the new points and submit to the government.

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2.2.3.1 New Station Markers

a. New Station Markers must be staggered on every other guide post on the upstream and downstream sides of the crest of the dams. The must also be placed on the toe on the dam, as shown on the drawings. The Marker must be at least 8 inches wide by 24 inches tall, aluminum or steel, mounted vertically and centered on the guide post with stainless steel fittings. The markings must be porcelain enamel, resistant to rust or discoloration over time, with black lettering with a white background, similar to water staff guages. Station Markers must have the stationing clearly visible from the downstream and upstream direction.

2.2.3.2 Survey Measurement Point Markers

a. Carsonite CIC markers must be installed next to all measurement points and meet EP 310-1-6a USACE signage standard requirements.

2.2.3.3 Guide Posts

a. Guide Posts must be 2.875 inch O.D. Schedule 40 galvanized steel pipe guide posts, with a galvanized round steel cap. Must be installed every 20', on the even, new dam stationing. Every 100' on the 100' even stationing, Guide posts must have stations identifed per EP310-1-6A USACE signage standard, visible both downstream and upstream. See 2.2.3.1. Must be installed in a 16 inch concrete filled steel pipe dug 3.0 feet into the ground.

2.2.4 Strong Motion Accelerographs

a. The Contractor must provide site access to the USGS for removal of existing accelerograph instruments and installation of new accelerograph instruments. After the existing accelerograph instruments have been removed by the USGS, the Contractor must remove the accelerograph housing, concrete pad, solar panels security enclosures, power feed, and fencing at each accelerograph site. After the Contractor has constructed and installed the new accelerograph housing, concrete pad, power feed, and fencing at each accelerograph site the Contractor must notify the Contracting Officer who will in turn will notify the USGS that all necessary preparations have been made for installation of new accelerograph instruments. USGS will remove and install all accelerographs on the job site.USGS will remove and install all accelerographs on the job site. The contractor must provide access to USGS.

b. The power supply for the accelerograph recorders must be directly connected with backup grid charged storage batteries of minimum 400aHr capacity.

2.2.4.1 Outside Accelerograph Housing and Installation

a. Accelerograph Concrete Pads and preparation: Install Accelerograph pads to the dimensions shown on the drawings.

b. Install Accelerographs housings pads on both abutments of the Auxiliary and Main Dam prior to construction at the approved locations for monitoring during construction. Prepare the concrete pads and subgrade according to the accelerograph manufacturer's instructions and drawings.

31 09 13 - 11

c. Accelerograph housing: Install the Model NE412000 WA20500 enclosure manufactured by Hubbell Power Systems or similar in locations as shown on the Drawings. Submit Accelerograph Housing Locations and Power Plan It must have two locking swing doors with vents as shown on the Drawings. Each housing must have 110/120v power and Cat 6 ethernet cable running through a separate 2" rigid aluminum conduit to the housing, with the appropriate power and ethernet receptacle installed in the housing. The 2" rigid steel conduit must be buried or encased in concrete with 6 inches of cover on all sides of conduit. Each housing must have a plastic engraved plaque installed on the side of the housing. The plaque must be a minimum dimension of 2 inch by 4 inches, with the correct instrument name engraved on it in white, minimum font size of 12, with a dark background.

d. Accelerograph batteries: Furnish and install 12 Volt batteries with a minimum capactiy at 100 degrees celsius of 84.5 Amp hours, 20 degrees celcius of 73.6 amp hours, and an approximate weight of 52 pounds.

Lead calcium batteries with posts made of forged terminals and bushings are acceptable.

e. Battery Box: Furnish and install commercial grade battery boxes with four corner fastening system, large cable entry holes for heavy gauge wire (up to 2/0 AWG), meets United States Coast Guard (USCG) Code of Federal Regulations 183.420, similar to NOCO Incorporated model HM426 Commercial Battery Box. Minimum internal dimension of 14.6 inch Length by 10.5 inch width by 11.5-inch height.

2.2.4.2 Main Dam Tower Accelerograph and MEMS Tiltmeter housings

a. General - All cabinets and enclosures must be watertight, with watertight conduit connections. 2" aluminum rigid conduit must connect all cabinets on all levels to each other and main power and communication. The smaller cabinets must have fast operating clamps, similar to Hoffman Model AC23SS.

b. Top of Tower Elevation approximately 2654 - Main cabinet must be a minimum of 72"x36"x18" 12 gauge type 304 stainless steel, similar to Hoffman A72361855FSN4. The cabinet must be mounted on a siesmic mounting plate kit, similar to Hoffman ASMP12SS. This cabinet must have 3 shelves. The top 3 shelves must have 2 power and category 5 receptacles and wiring per shelf. The bottom of the cabinet must have a power receptacle. Plugged or wired LED lighting must be installed on the inside of the cabinet. There must be a wall-mounted cabinet, minimum of 16"x14"x6" type 304 Stainless Steel, 14-gauge, similar to Hoffman A1614CHNFSS, with fast operating clamps, similar to Hoffman Model AC23SS.

c. Mid Floor - Install near elevation 2547.76 ft, 3-feet above the stair floor on the wall, vertically mounted, upstream side. This cabinet must be a minimum of 24" x 20" x 10", type 304 Stainless Steel, 14 gauge, similar to Hoffman A24H2010SSLP3PT.

d. Bottom Floor - Install near elevation 2484, there must be two cabinets.

One floor mounted and one wall mounted. They must be a minimum of 16"x14"x6" type 304 Stainless Steel, 14 gauge, similar to Hoffman A1614CHNFSS, with fast operating clamps, similar to Hoffman Model

AC23SS.

e. Battery Charger - Furnish and install battery chargers at all locations

31 09 13 - 12 with a 10 Amp, 115V on board capacity. Input Voltage 100 to 130 volts AC, 50 to 60 Hz, Output voltage 12 volts. Output cables must fit furnished battery above. Recovery time for charging must be 6 to 8 hours.

2.2.5 Staff Gage

a. Provide staff gage with black on white markings at the stilling basin downstream of the main dam. The staff gage must be heavy 16-gauge iron metal core covered with a baked-on durable porcelain enamel finish for corrosion and discoloration resistance. The staff gage must have marks at a minimum of every tenth of a foot. The size of the marks must be at least Style E staff gage by Stevens Water Monitoring Systems, Inc., Portland, Oregon, or approved equivalent.

b. The staff gage must have number plates to show the depth of water at every foot to NAVD88 elevations. The number plates must be a minimum of two inches wide and three inches high each and must be black on white. The number plate must be durable porcelain enamel finish for corrosion resistance.

2.2.6 Hour Meter

a. Supply a digital hour meter compatible for each sump pump at the downstream of the Auxiliary Dam. The hour meter must have at least a minimum 8-digit LCD display. The hour meter must be able to record and display up to 99,999.9 hours, rollover and continue timing. It must have memory to retain data for at least 25 years. The hour meter must require little to no maintenance.

2.2.7 Two Inch Parshall Flumes at Main and Auxiliary Dam

a. Furnish a 2 inch Parshall Flumes similar to Open Channel Flow's Manufactured Stainless Steel 2 inch Parshall Flume. The flume must have two staff gages. Install the flume in the manholes, as shown in the drawings.

b. The flume must have two stilling wells, capable of utilizing a float and automated reading equipment. The automated equipment must be Geokon Model 4675LV or approved equivalent. Wiring must be enclosed in the manhole in a conduit and connected to the automation equipment outside of the manhole in the same type of enclosure as the piezometers.

c. The flume must have visual staff gages denoted down to 0.01-foot increments, installed per manufacturer's instructions.

d. Flume installed at main dam to be a rectagular, stainless steel, locking enclosure with 2 float wells, and the same automation equipment as the other weirs. It must have a 6 inch thick concrete base for the entire enclosure to rest upon. Each housing must have a plastic-engraved plaque installed on the side of the housing. The plaque must be a minimum dimension of 2-inch by 4-inch, with the correct instrument name engraved on it in white, minimum font size of 12, with a dark background.

e. Flume flow tables, equations, and manufacturer's maintanence instruction must be provided to the government.

31 09 13 - 13

2.2.8 MEMS TiltMeters

a. Supply biaxial MEMS tiltmeters and install at approximately the following elevations: 2484.95 ft (operating flow above the gate chamber and conduit), 2547.76 ft (rock and embankment soil interface), and

2654.00 ft (top of new tower) in the main dam control tower for monitoring tilt of the control tower. Geokon MEMS tiltmeter 8003D-2, with a geoNet Wireless Network Model 8800 or equivalent to provide wireless connection, with antenna, and mounting bracket. These must be mounted on the biaxial mounting bracket which is affixed to the structure. The purpose of these instruments is to measure instantaneous tilt during siesmic events.

b. Supply field datalogger (FDL) with flexible input and output capabilities suitable for interfacing to the MEMS tiltmeter sensors, transducers, relays and other control devices. The FDL should be located in the upper cabinet, upper level of the control tower and communicate and collect all data from the 3 MEMS Tiltmeters in the tower. An FDL must be capable of executing its specific tasks autonomously, without intervention of control from a computer or laptop. All FDL system software and application-specific programming must be in non-volatile memory. Any measurement data queued for transmission to another network node must be stored in battery-backed memory or flashcard memory cards integrated with the ADAS FDL. The FDL must interface directly with the MEMS tiltmeter sensors and provide user programmable sensor excitation and warm-up. This includes, but is not limited to, MEMS excitation milliamperes and DC resistance. In addition, digital input channels must be available to measure discrete inputs or provide event counting and time interval measurement capabilities.

c. Field datalogger must operate utilizing power supplied by direct power supply. Power supplies must be sufficiently sized to supply the FDL with the necessary current such that the FDL can operate.

2.2.9 Cables

a. Provide cables compatible with the vibrating wire open tube piezometers, floatwells, and MEMS tiltmeters for installation as required. Cables must be sealed and affixed to the instrument at the factory with sufficient length so that splices will not be required.

Lengths required must include lengths in drill holes, and an additional ten feet must be provided to allow for slack in the cables. All cables must be free of holes, blisters, or other imperfection.

b. Each cable must be permanently labeled with the serial number, model number,open tube piezometer or MEMS tiltmeter number as specified in the drawings, and manufacture date of the associated instrument. The label must be placed at every five-foot interval for the initial and last 20 feet. The label must be factory attached where it is manufactured. If a label cannot be affixed to the cable, a label must be created of weatherproof material and affixed to the individual instruments, giving the same information as above.

c. All cables must be enclosed and protected in galvanized steel conduit.

No part of the cable must be exposed to the environment.

31 09 13 - 14

2.2.10 Grounding System

a. The grounding system must consist of 5/8 inch standard copper grounding rods driven into the ground. The grounding system must satisfy the IEEE minimum grounding requirements for sensitive electronic equipment as presented in IEEE Std 142. Grounding rod must be installed inside the enclosure with enough grounding cable slack to pull surge protector and data logger out of the security closure without disconnecting.

b. Transient protection must be used with the grounding system. Provide surge protection for all the vibrating wire piezometers and MEMS tiltmeters.

2.2.11 Surge Protection

a. Batteries must be fuse protected. AC input must be fuse protected and surge suppressed for transients. All ancillary electrical devices must be surge protected, including radio transmitter outputs. At a minimum, surge protection module must be located where the instruments daylight from a drill hole or open tube piezometer and at any junction box.

2.2.11.1 Conduits, power, and communication

a. All accelerograph housings outside of the main dam tower must have 2 conduits to each housing. These conduits must be 2 inch rigid galvanized steel. One conduit is for power 110/120V, the other is for communication, cat 6 line. Piezometers on the crest of either dam or along power lines shown in the drawings must have 110/120v power supplied as well.

PART 3 EXECUTION

3.1 EXAMINATION

3.1.1 Access

Access will be made available to Government geologists or other representatives during all drilling, backfilling/grouting, and/or instrumentation installations within boreholes through or near the embankment.

3.1.2 Instruments And Installations

The Contracting Officer will examine all instruments and installations immediately following completion of that subpart of the project. The Contracting Officer will prepare a written report documenting the instruments inspected, their functional state and any action items required for progress of the works.

3.2 PREPARATION

3.2.1 Protection

Submit before construction begins an Existing Instrumentation Preservation Plan Provide adequate security and protection of the instrumentation during the entire period of construction, including proper grounding and lightning protection. Measures must be taken to ensure that no instrument or component of the instrumentation system is damaged, vandalized or otherwise destroyed. These measures must be submitted to the Contracting

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Officer for approval prior to execution. Any instrument, sub-system, or system that is damaged, vandalized, or otherwise non-operational prior to the construction project's completion, must be replaced, reinstalled, and calibrated, within 2 weeks of destruction at no additional cost to the Government.

3.3 INSTALLATION

3.3.1 Instruments

a. Install each instrument in strict accordance with the instrument manufacturers' installation specifications. The instrument manufacturer must be on-site to provide installation instructions to the Contractor and the Contracting Officer prior to installing any instruments. Submit a List of proposed subcontractorsbefore installation. The instrument manufacturer must be present for the installation of the first of any given instrument type. The Contractor is responsible for the instrument manufacturer's total costs for providing a field representative at the project site including hourly labor rates, travel, and lodging costs.

b. Use extreme care when handling sensitive instruments. Contact the instrument manufacturer for handling precautions.

c. Perform and document calibration and operational checks on each instrument prior to and after installation. The Contracting Officer may perform seven day burn-in and endurance tests on any instrument.

Manufacturer's Calibration Data Sheets, Manufacturer's Warranty, and Contractor's Warranty for Installationmust be submitted to the government. Installation procedures and details must be submitted to the government.

d. Make all terminations and initial readings of the instruments in the presence of the Contracting Officer. Survey the exact installed location of each instrument immediately after installation. Submit the initial readings and other installation details within one week of installation. A standard form documenting the installation must be prepared for each instrument and submitted to the Contractor and Contracting Officer. The survey datum must be NAVD 1988 and NAD 1983.

e. Maintain all instrumentation installations in progress and immediately repair or replace, as deemed necessary by the Contracting Officer, any damage to installations in progress, or installations completed, at no cost to the Government.

f. Open tube Piezometers: Install instruments at the elevations shown on the drawings. The piezometer tip and screen must be installed at the intended layer (i.e. filter, drain, foundation, etc). The proposed open tube piezometers through the embankment must be installed and brought up as backfill material (i.e. filter, drain, rock fill, random fill) is placed. Regardless of installation or drilling method, the casing must be straight and plumb. The backfill material must be compacted with a hand tamper to achieve the required relative compaction in accordance with Section 31 00 00 EARTHWORK and 35 73 13 EMBANKMENT FOR EARTH DAMS. To avoid twisting of the casing by compacting around the riser alternating with clockwise and counter clockwise directions. Replace any casing or open tube piezometers that are damaged by the compaction or construction equipment during construction. Construct access to all open tube piezometers. A

31 09 13 - 16 mechanism on the website must allow USACE to automatically retrieve data. The access must conform to all safety requirements outlined in the most recent version of EM 385-1-1.

3.4 MONITORING

Begin taking hourly readings of all existing instruments and proposed instruments as soon as they are installed, with the exception of survey monuments and seismic instrumentation. Submit all manufacturer's calibration sheet installation zero readings elevation and coordinate of the instrument, and any as-built Drawings within two business days after the installation of an instrument in a Field Monitoring Report. Submit all instrument readings weekly in an Instrumentation Report in electronic tabular form. The Daily Instrumentation Report must be made available on a secure website for download at 0900 hour each day. A notification must be sent to a list of contacts provided by the Contracting Officer when the Daily Instrumentation Report is ready for download. All instrumentation readings taken during the contract must be available on the same secure website for download. Submit the Daily Instrumentation Report after quality control review of the readings. Dewatering pumping must meet separate requirements as outlined in Section 31 23 19.13 Dewatering.

3.4.1 Survey Measurment Point Monitoring

a. Perform a monitoring survey at all survey measurement points post crest construction completion. Survey accuracies must be at a level needed to identify movements to a hundredth of a foot in horizontal and vertical directions. Survey points must be given in NAVD 88 and NAD 83 coordinates and new station and offset.

3.4.2 Accelerographs, Seismic Alarm Device, and MEMS Tiltmeters

a. Perform status check of all strong motion instruments weekly during construction of the dam safety project. At least one accelerograph and associated alarm must be operational at any given time during construction. Once accelerographs, Seismic Alarm Device, and MEMS tiltmeters are installed, perform status check weekly.

3.5 TESTS, INSPECTIONS, AND VERIFICATIONS

Proper function and continuity of all instruments must be confirmed upon delivery and immediately after installation. A field check and calibration of vibrating wire piezometers and flume for function and accuracy must be conducted by the Instrumentation Contractor and verified by the Contracting Officer, prior to installation and after installation for the duration of the contract, as needed.

Manual Readings must be taken from each installed vibrating wire piezometers, vibrating wire floats, SAD, MEMS tiltmeter, accelerographs, and staff gages every 7 calendar days for the duration of the contract, unless otherwise noted.

All piezometers must be inspected pre construction and post construction with a video camera recorder. The footage must be submitted to the government.

Submit the pre-installation test of the instruments and manufacturer's calibration sheet before installation.

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3.6 MANUFACTURER'S FIELD REPORTS

Submit manufacturer's field reports and Manufacturer's Warrantyfor work done by the manufacturer. Submit field reports within five days within the completion of installation of each vibrating wire piezometers and vibrating wire float well. The first field report for each instrument must include at a minimum manufacturer's calibration datasheet, stationing, offsets, elevation, and coordinates of instrument, pre-installation test reports, readings in tabular format and graphical format, and any installation or as-built drawings. Subsequent field test reports of the installed instrument must include at a minimum weekly readings in tabular format and graphical format, graphical format must be in NAVD elevation with instrument names clearly identified, date of readings, and all calculations. A password protected internet site is the preferred method of data submittal and plotting.

3.7 TEST REQUIREMENTS

3.7.1 Tests

Test all systems and sub-systems as completed and ready for service before final payment for this product is made. Video inspect new and existing open tube piezometer instruments to ensure proper installation prior to payment.

3.7.2 Inspections

The Contracting Officer will inspect completed sections of the work. Give a minimum of ten business days notice prior to installation of any instruments.

3.8 FINAL DRAWINGS

Submit final drawings including data sheets showing the exact installed location, the instrument identification number, the instrument type, installation date and time, station, offset, and coordinates. The survey datum must be NAVD 1988 and NAD 1983. The drawings must include details of installed instruments, accessories and protective measures including all dimensions and materials used. Amend drawings during construction to show changes in instrumentation installations, as approved by the Contracting Office.

3.9 OPERATION AND MAINTENANCE (O&M) MANUAL

Prepare and submit a complete Operation and Maintenance (O&M) Manual for all instrumentation installed as part of the work. The Operation and Maintenance (O&M) Manual must include a detailed explanation of how to operate the combined systems installed as part of the work. Include manufacturer's manuals as appendices in the Operation and Maintenance (O&M) Manual. Provide the Operation and Maintenance(O&M) Manual for review and approval 90 days prior to completion the project.

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