140G0321Q0138_SOW.docx

Project Summary The U.S. Geological Survey (USGS) has a requirement for a contractor to build the site infrastructure for seismic stations throughout Northern and Central California, which will be used as part of the Earthquake Early Warning (EEW) system. The project scope consists of three elements:

1. Construction of the “basic” NCSN site which includes the installation of the equipment vaults, DC power system (including solar array), grounding system, telemetry infrastructure, and drainage system that comprises a seismic station.

2. Construction of the basic site above, with the addition of a shallow posthole.

3. Construction of a posthole at an existing NCSN site

In some cases, removal of existing seismic infrastructure will be required. Skills necessary include demolition, excavation, concrete, electrical (specifically DC and solar), general construction, and landscaping/site restoration.

Appendix A.1 is a map of possible sites, showing the geographical scope of the project. Appendix A.2 is the master list of possible sites. USGS reserves the right to change Appendix A.2 within the general scope of this effort in terms of geography and work requirements. Selection of sites to be built depends on acquisition of permits and access issues which are currently being worked on by the USGS. Appendices B.1-B.3 are schematic diagrams of the three different elements. Other appendices provide additional details.

The contractor will otherwise have wide discretion in scheduling work, subject to any specific limitations discussed herein.

Table of Contents

Statement of Work

Notes and Responsibilities

1) [Schedule] The Infrastructure Contractor shall provide deliverables in the form of a summary every 3 months to the USGS with a timeline of work to be completed and regular updates on progress throughout the project.

2) [Transportation] The Infrastructure Contractor shall provide transportation to and from the job site for personnel, materials, equipment needed for fabrication, drilling and installation, and debris disposal.

3) [Purchasing] The Infrastructure Contractor will provide all the needed parts for installation of seismic stations. The USGS provides the Infrastructure Contractor with a parts list and construction diagrams in the Appendices. Some additional materials will be needed for site completion that will not be explicitly listed on the parts list, such as nuts and bolts, zip ties, etc. The contract must adhere to the specific part numbers for items in the Bill of Materials; if the contractor cannot find the specific part, notify the USGS lead to discuss alternatives. The USGS will provide the following items: solar pipe mounts (not antenna pipes), battery/radio enclosures, instrument enclosures, “Do Not Disturb” stickers, and GPS antenna. It is the Infrastructure Contractor’s responsibility to pick these items up at the USGS warehouse in Menlo Park. The Infrastructure. Contractor will also need to provide the equipment needed to drill 1-3 meter depth postholes.

4) [Hardware] All nuts, bolts, screws, and associated hardware shall be either stainless steel or galvanized. If not specified, check with USGS lead.

5) [Training] All laborers must visit a seismic station with USGS staff to develop an understanding of what is required to install a seismic station. Additionally, any other required training by law must be completed before arriving at applicable sites.

6) [Crew contact] Each crew must declare a lead contact. It will be the lead contact's responsibility to coordinate with USGS staff and relay any scheduling, site information, etc. to all laborers on the crew. The lead contact must be on-site at all times during installation. The lead contact must possess and regularly consult the Scope of Work and Installation Guidelines documents. The lead contact must not be the employer.

7) [Scheduling] Crew contacts and general contractors will work with USGS staff to plan installation schedules. Installation work will be scheduled regionally when possible to promote efficiency. One USGS personnel shall be onsite during the installations to provide guidance to the contracting crew and ensure complete compliance to the statement of work. Communication between the lead contact and USGS staff will be needed to coordinate this arrangement.

8) [Work Hours] Some sites may have restrictions imposed by the landowner that limit or modify work hours.

9) [Equipment checklist] Each crew must develop an appropriate equipment checklist and provide USGS staff with copies before the commencement of work. Before departing for installation work, the crew must review their equipment checklist to ensure sufficient supply. If a crew arrives at a site with insufficient supplies all crewmembers must clean-up appropriately, leave the site, and prepare to return at a later date.

10) [Overnight Storage of Materials and Equipment] Crews shall check with the USGS lead for each site to determine what materials, equipment, and vehicles can be left overnight at the site. For sites on public lands, overnight storage is not recommended.

11) [Site meet] For each crew’s first visit to their first and second site, they must meet a USGS staff member at a predetermined off-site location to discuss site rules and access. They will follow USGS staff to the site and then discuss the site layout and duties when on site. No parties may access a site their first time without first participating in a site meet. After the first 2 joint site visits, the USGS Lead will decide if further site training is necessary. If no more joint site visits are deemed necessary, then the Infrastructure Contractor will be responsible for their actions while accessing the next sites. The USGS Lead should be consulted to ensure access has been granted by the landowner.

12) [Site Access Rules] When the contractor reaches the point at which they enter private property, several rules must be followed while working on the premises. Be aware that additional rules may be required by the landowner (see Appendix A.2, Stations List).

a. When required, make sure the USGS Lead contacts the landowner or manager 48 hours prior to entering their property.

b. Enter and exit the property by the same route every time. Do not wander off course.

c. Always leave gates as you find them, unless instructed to do otherwise. For example, if a gate is locked when you arrive, lock it behind you.

d. Use 4WD on unimproved dirt roads at all times, if available.

e. Do not drive on unimproved dirt roads within 24 hours of 0.1” of rain or more.

f. All vehicle drivers must have valid state drivers’ licenses.

13) [Environmental]

a. If at any time while working on the site the contractor digs up or discovers any foreign objects, work at the job site must stop immediately and the contractor must call the USGS lead. Foreign objects include bones, artifacts, historical items, buried pipes or wires, evidence of a historical site, and any other similar items.

b. Any piece of equipment the contractor brings to the work site should be as devoid as possible of foreign materials (e.g. dirt from another project) or possible invasive species (e.g. plants stuck to the undercarriage of a truck). Remove those items before arriving on the property and remove new debris before leaving the property.

14) [Remove existing infrastructure] Unless instructed otherwise, for construction of sites with new “basic” NCSN site infrastructure or new “basic” site infrastructure plus a shallow posthole, pull up old vault(s); remove antenna mount(s); remove all cabling; dispose of all materials and trash except the following items: VCO, radio transmitter, sum amp, and sensor (with cable—do not cut the cable). Return these items to USGS when convenient. Restore the area to a natural state that closely mimics the current conditions. The site list (Appendix A.2) shows which stations may require removal of old equipment. Details can be provided at site walk through.

15) [Site preparation] USGS staff will mark locations of battery/radio and instrument enclosures prior to or the day of the contractor’s first visit. Contractor shall notify Underground Service Alert as necessary. USGS will also mark the location of any other unusual site features, such as trees and plants to avoid, and/or additional components to install, such as fencing.

16) [Safety]

a. BE FIRE CONSCIOUS. Wildfires can easily be started any time of year. The Infrastructure Contractor crew shall have available at least three (3) class ABC fire extinguishers at all times with a minimum use time of at least 10 seconds and a dedicated water source to be used only for fighting fires OR three (3) Indian pumps or equivalent brand. All crew members shall know how to access and use this equipment. Contractors shall use a fiberglass fire blanket when CAD welding, or using other tools that have the potential to generate sparks.

b. Absolutely NO smoking while on site unless you are inside your vehicle. Cigarette butts must be extinguished and stored within the vehicle.

c. Use all appropriate Personal Protective Equipment and safety practices at the job site.

d. Do not disturb the wildlife and plant life (outside of the site footprint) while on private property. Do not disturb grazing animals.

e. WILDFIRES. The USGS safety protocols call for field operations to cease when fire approaches within 15 miles of a worksite. USGS staff will also cease field work when the AQI exceeds 200

f. COVID-19 – Contractor shall provide the USGS with COVID-19 safety protocols that their crew(s) will adhere to when engaged in travel and work pertaining to the USGS contract.

17) [Documentation] Photograph all specified installation actions (see “Infrastructure Contractor Checklist” for a complete list), particularly including conduit trench, ground ring, and concrete forms (before concrete is poured). Where depth or length is specified, photograph measuring tape showing required measurement.

18) [Excavation] Some sites may not allow for heavy equipment and may require all excavation be done by hand. Consult site list in Appendix A.2 for site-specific requirements.

19) [Finish] Ensure site is free of trash, microtrash, debris, rubble or other foreign or objectionable material. All construction trash and trash collected from the removal of existing infrastructure must be removed from site and properly disposed of. Rake area to level out any ruts or berms and restore a natural appearance to the site.

Work requirements

1) Preparation

a) Remove weeds, grass, and small brush (up to 5 ft tall and diameter) from the footprint of the new or upgraded site.

b) Unless otherwise instructed, remove and properly dispose of all existing seismic infrastructure at the work site. Consult with the USGS lead to understand if there are any portions of the existing site to not remove.

c) It is the infrastructure contractor’s responsibility to contact Underground Service Alert if required.

2) Construction The infrastructure consists of six main components: battery/radio enclosure; instrument enclosure; DC power system (including solar panel(s), solar mounting brackets, solar controllers, batteries, surge protection device (SPD), and associated cabling); grounding system (including ground rod, ground wires, bus bars, and a ground ring); telemetry system (including antenna, coaxial cables, and SPD); and drainage system. The enclosures shall be placed according to locations marked by the USGS lead prior to installation.

a) [Battery/Radio Enclosure]

i. Dig an appropriately sized hole to fit a 2x6 concrete form with a nominally flat bottom. The top of the battery/radio enclosure form should be level in all directions and sits at grade. The orientation of the rectangular hole should have the side with the solar/antenna pipe oriented roughly east-west, thus facing south.

ii. Use one steel mesh reinforcing mat. Center the mat top to bottom and side to side in the form, making sure that nowhere the steel extends to daylight.

iii. Use a reproducible template/jig to set bolts in place at specified points (See Appendix B.4). These bolts will be used to attach the enclosure and solar mounts.

iv. Pour concrete. Use a high-early-strength concrete such as Quikrete5000.

v. Use a trowel to smooth and flatten the top of the concrete.

vi. Let cure before removing the forms and continuing work around the enclosure.

vii. Bolt the enclosure to the concrete pad.

viii. Install conduit connectors and conduit to the outside of the box.

ix. Install foam insulation. Use Rockwool Comfortboard 110.

x. Install latches and “A389” USGS locks and apply a “Do Not Disturb” sticker.

b) [Instrument Enclosure]

i. Dig an appropriately sized hole to fit a 2x6 concrete form with a nominally flat bottom. The top of the enclosure form should be level in all directions and sits approximately 16-20” below grade. The orientation of this hole is not critical and can be oriented in whatever direction is most convenient. However, with this hole it is critical for the bottom of the hole to be undisturbed and not contain any loose soil. We recommend digging the last several inches by hand if possible, to avoid disturbing the bottom of the hole. Remove any loose soil so that coupling between the concrete and dirt/rock is optimal.

ii. Dig additional holes, proceed with a or b, depending on whether a posthole is required:

a) At Basic NCSN sites (with no posthole), at each inside corner of the main hole, dig an additional 6” diameter hole (“pier”), 10” deep (total of 4 more holes). For 2’x3’ instrument enclosure only.

b) At sites with postholes: Posthole to be centered within the concrete pad and instrument enclosure. If bedrock is present within the first half meter of the surface, the posthole must be a minimum depth of one meter. If bedrock is reached between 0.5 and 3 meters depth, the posthole must extend into the bedrock a minimum of 0.5 meters. If no bedrock is present, posthole depth will be the maximum of 3 meters. The posthole shall be 10” in diameter. Ensure that the 6” PVC casing is set to +/-1° of 90° vertical. PVC should extend above the concrete pad 6-8”. Once the PVC is set to vertical, the PVC should be grouted into place. When the grout is set, the contractor may continue onto the pouring of the concrete pad.

iii. Use one steel mesh reinforcing mat. Center the mat top to bottom and side to side in the form, making sure that nowhere the steel extends to daylight. Using bailing wire, tie on 8” long J-bolts (or bent rebar) to the mesh such that the J-bolt dangles freely in the pier hole (see Appendix B.5).

iv. Photograph the hole such that the USGS lead can sign off for compliance.

v. Pour concrete up to the level of the steel mesh. Use a high-early-strength concrete such as Quikrete5000. Make sure the concrete fills the piers and that the reinforcing J-bolt sits such that it is not touching the edges of the pier holes. The water-to-concrete mix is particularly important for this enclosure. Cracking (after curing) is not acceptable.

vi. Carefully set enclosure on steel mesh and concrete making sure it is centered in concrete forms and that the top is level.

vii. Continue pouring concrete until the form is filled. Make sure the inside is at the same level as the outside.

viii. Use a trowel to smooth and flatten the top of the concrete. The inside should be particularly smooth and level.

ix. Let concrete cure before removing the forms and continuing work around the enclosure.

x. See Appendix B.6, D.6, and D.7 for special instrument enclosure/shallow borehole instructions.

xi. Install foam insulation. Use Rockwool Comfortboard 110.

xii. Install latches and locks and apply a “Do Not Disturb” sticker.

c) [DC Power System]

i. Install the powder-coated 3” pipe to the Battery/Radio Enclosure concrete pad. This pipe holds the solar panels and radio antenna as described in Appendices B.8.

ii. Mount the solar panel(s) to the pipe. Point the solar array due south (within +/- 3 degrees) with an angle of [latitude + 15] degrees up from horizontal (see figure below). Solar mounting brackets should be U type or equivalent type that guarantee maximum connection to the mast and must prevent movement during high wind events.

iii. Install and secure ½” Electriflex Type-LA conduit from the solar panel junction box(es) to the battery/radio enclosure. Secure conduit to the pipe mounts using stainless steel hose clamps at a minimum of 18” intervals. Use ½” conduit to connect solar panel junction boxes if more than one solar panel is called for.

iv. Dig a 12” deep trench in as straight a line as possible between the two enclosures. Install 1.5” Electriflex Type-LA conduit in the trench.

v. Install conduit connectors and conduit to the outside of the box. All conduit connections to the enclosures shall be made at least 3” above grade (in the Instrument Enclosure, that usually means the connection is just below the lid). Backfill the trench with native soil and compact with feet or a tamping tool.

vi. Run 2-conductor cable, LMR-240 coax (GPS), Cat 6, and 6AWG ground wire through the conduit between the Battery/Radio Enclosure and the Instrument Enclosure. The cable should be long enough to leave 6’ extra in both enclosures. Coil the ends and tape up the cut ends using Super 33+ electrical tape to protect the ends.

vii. Install Nixalite bird deterrent spike strip to the top of the top-most solar panel.

viii. Clean glass on solar panel(s).

d) [Grounding System]

i. Install bus bars in both the Battery/Radio Enclosure and in the instrument enclosure as specified in the Grounding System Detail diagram from Appendix B.10.

ii. Dig a minimum 12” deep trench around battery/radio enclosure foundation (may use space created when removing concrete forms). Install a 2AWG tinned copper ground wire ring around the enclosure. Exothermically weld both ends to the ground rod. Remember to use fiberglass fire blanket when exothermically welding. Backfill trench with native soil and compact.

iii. Drive an 8-foot, 5/8” ground rod into the ground within 2 feet of the battery/radio enclosure and exothermically weld it to the ground ring. If the ground rod cannot be driven vertically, it can be driven in at an angle of no more than 45 deg. from vertical. DO NOT CUT ground rod. If ground rod cannot be driven in completely, drive ground rod to refusal, then dig a 12” deep trench adjacent to it and bend the ground rod into an “L” and place the horizontal section in the trench. Then, exothermically weld the horizontal end of the ground rod to the ground ring.

iv. Install other grounding components and make electrical connections as per Appendix B.10. All ground wires shall have a green insulating jacket (except for ground ring).

e) [Telemetry System]

i. Antenna mounting:

1. For yagi-style antennas, with azimuth between 276 and 84 (northern semicircle):

a. Install a 3” to 1.5” pipe reducer to the top of the threaded solar pipe.

b. Install a 2ft long pipe (1.5” galvanized) to the pipe reducer. Tighten with a pipe wrench. Add a 1.5” fence pipe cap to the top of the pipe.

c. Mount antenna to the top of the pipe mount, horizontally polarized. Ensure that no antenna element is directly above the solar panel(s).

d. Align the antenna to the listed azimuth (Appendix A.2). Do not overtighten the stainless steel U-bolts.

2. For yagi-style antennas, with azimuth between 85 and 275 (southern semicircle)

a. Install an offset antenna mount to the solar pipe (see Appendix B.8).

b. For 900MHz-style antennas, install a pipe (1.5” x 3’ galvanized steel pipe) to the end of the offset mount. Make sure the pipe extends to at least 1ft above the top of the solar pipe.

c. For 165MHz-style antennas, the solar array will have to be installed in a higher position than normal and above the antenna. A 9ft tall solar/antenna pipe will be required. Install the solar array such that the bottom of the lowest solar panel is no lower than 7.5ft above ground level. This may require the addition of a pipe extension. Install two pipe standoff brackets to the solar/antenna pipe at a level such that the 165MHz yagi will have at least 18” separation to the solar array and about 6’ above ground level. Space the brackets a minimum of 18” apart and mount a 1.5” x 2’ galvanized steel pipe to the ends of the brackets to hold the antenna mount. See Appendix B.8.

d. For 900MHz-style antennas, mount the antenna to the top of the 1.5” pipe mount, horizontally polarized. Ensure that no antenna element is directly above the solar panel(s).

e. Align the antenna to the listed azimuth (Appendix A.2). Do not overtighten the stainless steel U-bolts.

f. Add a 3” fence pipe cap to the top of the solar pipe.

3. For cellular antennas:

a. Install a 3” to 1.5” pipe reducer to the top of the threaded solar pipe.

b. Install a 2ft long pipe (1.5” galvanized) to the pipe reducer. Tighten with a pipe wrench

c. Mount a right-angle bracket to the top of the 1.5” pipe. Face the bracket away from the solar panel(s).

d. Mount the antennas to the angle brackets.

ii. RF and GPS Coax – Install 1” Electriflex Type-LA conduit to protect each coax cable (total of 2). One end should terminate at a point 1ft below the respective antennas and the other on the side of the battery box. Secure conduits to the solar pipe and mounts using stainless steel hose clamps at a minimum of 18” intervals.

iii. Mount the appropriate frequency (DC-6Ghz) surge protection devices (SPDs) to the main bus bar inside the battery box.

iv. Run LMR400 coaxial cables in the 1”conduits and attach one end to the antenna connector and one end to the SPD (for both GPS and 900MHz).

v. Seal the antenna/coax connection with this method: first layer, starting on the end with the connector, tightly apply 3M/Scotch Super 33+ electrical tape in a continuous wrap to at least 3 inches back onto the cable jacket; second layer, starting on the end with the connector, tightly apply 3M Butyl Mastic Tape 2212 or Scotch Rubber Mastic Tape 2228 in a continuous wrap to at least 2 inches back onto the jacket; top layer, starting on the end with the connector, tightly apply 3M/Scotch Super 33+ electrical tape in a continuous wrap to completely cover the second layer.

vi. Apply a thick plug of clear GE SiliconII caulking to the open ends of the 1” conduits near the antenna such that is seals moisture out of the conduit.

vii. Run CAT6 Ethernet cable with molded connectors through the 1.5” conduit between the Battery/Radio Enclosure and the Instrument Enclosure. The cable should be long enough to leave 6’ extra in both enclosures. Coil the ends and tape up the molded connectors using Super 33+ electrical tape to protect the connectors.

f) [Drainage System]

i. For Battery/Radio Enclosure:

1. Grade soil away from the enclosure

ii. For Instrument Enclosure:

1. Install a perforated 3” drainage pipe around the enclosure below grade as illustrated in Appendix B.9. Wrap with a soil cloth.

2. Connect ends with a wye. Install non-perforated 3” drain pipe in a trench from the wye on a downward grade out to “daylight”. Cap end of drain pipe with a perforated end cap to keep critters out.

3. Backfill trenches around all drain pipe with ¾” crush drain rock. Fill to a level to completely cover drain pipe and up to grade. Cover the drain rock with soil filter cloth.

4. Backfill native soil around the enclosure to a level about 4” below the bottom of the enclosure lid. Ensure that the backfill completely covers the drainage system and also grades away from the enclosure. Compact the backfill soil with feet or a tamping tool. Do not bury any condulets.

3) Finish, Clean Up, and Documentation

a) In a few cases a fence may need to be installed around the Battery/Radio Enclosure and solar panels to keep livestock out. See Appendix A.2, Special Considerations, for any sites where a fence is required. The 4-sided fence will consist of:

i) 4 pressure-treated 6”x6” posts, 1 in each of the 4 corners, sunk a minimum of 2.5’ deep.

ii) 3 (three) 12’L x 64”H powder-coated steel fence panels with appropriate hardware to attach to the fence posts.

iii) 1 (one) 12’L x 52”H powder-coated steel gate panel with appropriate hardware such that it can swing open (outward) to at least 45deg. and then latched closed (no lock is necessary).

iv) It should be installed so that no fence panel shades the solar array and so that there is enough room for a person to work in front of the enclosure.

b) All construction debris shall be cleaned up and removed from the site.

c) Concrete wash out shall be contained and removed from the site.

d) All disturbed ground shall be graded to match surrounding landscape as best as possible. Break up large dirt clods and avoid piles of rocks.

e) Cut vegetative debris shall be either dispersed (in the case of grasses) or stacked neatly in a manner that does not present a significant eyesore on the landscape.

f) Digital photographs shall be taken during site construction to properly document work completed and so that non-visible (e.g. ground ring) components can be verified as being completed. At least 3 additional photographs shall be taken after completion to document the main infrastructure of the site: the Battery/Radio/Solar system; the Instrument Enclosure; and one that shows the entire site.

4) Acceptance Testing

After the site is installed by the Infrastructure Contractor, the USGS lead will visit each site and use the infrastructure contract checklist to determine the completeness of job. If the job is determined to be incomplete, the USGS lead will notify the contractor of specific deficiencies. The contractor will determine a day in which to complete the tasks at the site and complete them in a timely manner.

Appendices List

APPENDIX A.1 – Stations Map

APPENDIX A.2 – Stations List See attached spreadsheet

APPENDIX B.1 – “Basic” seismic station schematic

APPENDIX B.2 – “Basic” seismic station with a posthole schematic

APPENDIX B.3 – “Basic” seismic station with a posthole retrofit schematic

APPENDIX B.4 – Solar/Battery Concrete Pad

APPENDIX B.5 – Seismic Enclosure Pad

APPENDIX B.6 – Posthole Schematic

APPENDIX B.7 – Backfilling Around the Enclosure

APPENDIX B.8 – Construction of Solar/Antenna Mast

APPENDIX B.9 – Drainage Detail

APPENDIX B.10 – Grounding Detail

APPENDIX B.11 – Battery Enclosure Power System and Wiring

APPENDIX B.12 – Seismic Enclosure Cabling

APPENDIX B.13 – Battery Enclosure Foam Detail

APPENDIX B.14 – Seismic Enclosure Foam Detail

APPENDIX C.1 – NC.LWPB

NC.LWPB – West Prospect Peak (40.59412, -121.37974) 2’x3’ seismic instrument enclosure with posthole build. Contractor is responsible for installing seismic enclosure, posthole, 80’ buried conduit connecting the enclosure to the USFS lookout, the NEMA box where the USGS will enter the building, as well as all drainage and grounding infrastructure. See drawings for details. Refer to Appendices B.5, B.6, B.7, B.9, B12, and B.14 for seismic enclosure installation.

APPENDIX C.2 – NC.LWPB, Site Layout

APPENDIX C3 – NC.GWKB

NC.GWKB – Walker Ridge (39.052609 -122.492332) Complete site build. Contractor is responsible for installing seismic enclosure, posthole, battery/radio enclosure, solar mast, buried conduit connecting the enclosures, as well as all drainage and grounding infrastructure. Approximately 40’ separation between the enclosures. 300W of solar and 4 SunXtender 100AH batteries. See drawings for details. Antenna will need offset mount (not pictured) to prevent the antenna from overhanging the solar panel (consult USGS for preferred offset mount). Contractor responsible for the purchase of all materials except for those indicated in the bill of materials. Layout/mockups of the site are below.

APPENDIX D.1 – NC.BTV

NC.BTV – Topo Valley (36.45528 -121.05797) Install a 2’x2’x2’ enclosure adjacent to the existing seismic enclosure. The enclosure to be partially buried leaving 6-8” or less of the top visible. In the center of the enclosure, a 6” PVC casing to be set and grouted in a 10” diameter x1-3 meter deep borehole. Borehole depth will be determined by the presence or absence of bedrock. If bedrock is discovered at, or close to the surface, the minimum depth of the borehole is 1 meter. The borehole shall not exceed 3 meters if no bedrock is present. If bedrock is found with 1-3 meters of the surface, the borehole shall extend at a minimum one half a meter into the bedrock. The borehole shall be within 1 degree of vertical. The enclosure will be connected to the existing seismic enclosure with 1.5” conduit. This will be duplicated at NC.GHGB, NC.GRT, NC.GSX. and NC.LTC.

APPENDIX D.2 – NC.GHGB

NC.GRT—Roundtop (38.93867 -122.67110)

APPENDIX D.3 – NC.GRT

NC.GRT—Roundtop (38.93867 -122.67110)

APPENDIX D.4 – NC.GSX

NC.GSX – Six Sigma Winery (38.84980 -122.52254)

APPENDIX D.5 – NC.LTC

NC.LTC – Tuscan Springs (40.20842 -122.12548)

APPENDIX D.6 – Posthole Enclosure Concrete Pad

APPENDIX D.7 – Posthole Schematic (Side View)

APPENDIX D.8 – Joining the Enclosures

APPENDIX D.9 – Seismic Enclosure Foam Detail

APPENDIX E - Bill of Materials

16-18 bags = LWPB 8-10 bags = BTV, GHGB, GRT, GSX, LTC

Grounding

Battery/Radio + Seismic Enclosure

Solar Mast / Antenna Mount

900MHz yagi antenna standoff: NC.GWKB

Miscellaneous

Provided by the USGS

Quantity may vary by site, see site specific notes

NC.GWKB

NC.GWKB and NC.LWPB

NC.BTV, NC.GHGB, NC.GRT, NC.GSX, NC.LTC

All Sites

APPENDIX F - Infrastructure Contractor Checklist To be used by USGS personnel following site build “Notes” provided after each section for missing items, incomplete task explanation, etc.

Battery/Radio Enclosure

Enclosure level

1 ½” conduit connections to enclosures at least 3” above grade

Oriented nominally east-west

Batteries installed, on wood blocks

Top of concrete smooth

Foam installed

Forms removed

Latches and locks in place

Enclosure bolted to concrete

“Do Not Disturb” sticker in place

Conduit to instrument enclosure buried min. 6” deep, backfilled completely, and compacted

No excess holes/water sealed

Notes:

Instrument Enclosure

Enclosure level

Posthole Vertical

Enclosure at correct height above grade

Posthole extends 6-8” above concrete pad

Top of concrete smooth with no cracks

Latches and locks in place

Top of concrete level

“Do Not Disturb” sticker in place

Forms removed

No excess holes/water sealed

Foam installed

Notes:

Solar/DC Power System

Pipe installed plumb, with proper bolts securing it to battery/radio enclosure

Power cable run through 1 ½” conduit

Solar panels with correct mount

6’ of extra power cable in both enclosures

Bird spike strip installed on top

Power cable coiled up at both ends

Solar array installed facing south

Terminal strip, solar controller, and solar SPD installed

Solar array installed with proper angle

Batteries are connected in parallel and wing nuts tightened

Solar panel(s) glass clean

Battery jumper cable between solar controller and batteries secured

½” conduit installed between solar panel and battery enclosure

Wiring is correct

Conduit secured to pipe with zip ties

Solar array values within specs:

Panels (if more than 1) have junction boxes connected with ½” conduit

Measured volts:

Power cable run between solar array and solar controller, and between panels if more than 1

Measured amps:

Notes:

Grounding System

Bus bars, standoffs in both enclosures

Ground rod no more than 45deg. from vertical and driven in completely

No hard kinks or bends in any wires

For ground rods that can’t be driven completely, alternative trench/bend method is followed

Proper lug connections throughout (one- or two-hole depending on the application)

Ground ring at least 12” deep

Connections to box and pipe have powder coat ground off

Ground ring is exothermically welded to ground rod

Correct gauge wire for each connection, all with green insulating jacket

Exothermic welds are clean and secure

Solar and coaxial cable SPD’s are mechanically connected to ground bar in battery enclosure

Ground wire to solar pole wing bracket

Ground wire runs through the 1 ½” conduit and is connected to each bus bar

Ground wire to solar panel frame (and between frames if more than one panel)

Conduit running to ground bar, and sealed with silicone caulking

Ground wire to bus bar in battery enclosure

Copper paste at all lug connections outside of the enclosures

Notes:

Telemetry System

Antenna mount

Conduit secured to solar pipe stainless steel hose clamps

GPS Antenna and Antenna Mount

SPDs are correct frequencies

Antenna azimuth and polarization:

Coax run through 1” conduit and secured at both ends

Measured azimuth:

Connection of coax to antenna is sealed properly

Polarization:

CAT6 run through the 1 ½” conduit between the 2 enclosures

2 Conduits (RF and GPS) with coax runs up to 1ft below antenna and the end sealed with silicone caulking

6’ of extra Ethernet cable in both enclosures, coiled up, and taped off

Notes:

Drainage System

For battery/radio enclosure:

Soil graded away from enclosure

For instrument enclosure:

3” perforated drainage pipe around enclosure

Trenches around drain pipe backfilled with ¾” drain rock

Drainage pipe wrapped in soil cloth

Drain rock covered with soil filter cloth

Ends connected with a wye

Native soil is backfilled covering drainage system, and is about 4” below enclosure lid

3” non-perforated drain pipe is trenched, on a downward grade

Backfill grades away from enclosure and is compacted

End has a perforated cap

Notes:

Overall Site

Site clean, no trash due to install

All nuts on brackets and mounts tight

Disturbed ground graded back to natural appearance

Old site equipment removed (if applicable)

Brush properly disposed

Distance between enclosures:

Notes:

Pictures Taken and Supplied

Battery/Radio enclosure excavation showing foundation preparation before concrete pour

Drainage system before native soil burial

Instrument enclosure excavation showing foundation preparation before concrete pour

Conduit trench between the enclosures

Ground ring trench

Overall view of battery/radio enclosure with solar array and antenna

Ground rod(s) and exothermic weld(s) to ground ring

Overall view of instrument enclosure

Drainage system before crush rock burial

Overall view of entire site image2.tiff image3.jpg image4.jpg image5.jpg image6.jpg image7.jpg image8.jpg image9.jpg image10.jpg image11.jpg image12.jpg image13.jpg image14.jpg image15.jpg image16.jpg image17.jpg image18.jpg image19.jpg image20.jpg image21.jpg image22.jpg image23.jpg image24.jpg image25.jpg image26.jpg image27.jpeg image28.jpg image29.jpeg image30.jpg image31.jpg image32.jpg image33.jpg image34.jpg image35.jpg image36.jpg image1.emf

Solar

Panel(s)

Pipe θ θ θ=Latitude°+15°

Typical 4-ch Freefield Installation.vsdx

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