Bldg 250 Parking Lot Lights SOW Rev A Jul 09.docx
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- FA4613-09-R-0016
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Bldg 250 Statement of Work
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SCOPE OF WORK
Install Parking Lot Lighting Bldg 250 F. E. Warren AFB, Wyoming Project #: GHLN 081088
Date: 1 Jul 2009
GENERAL REQUIRMENTS
High West Energy shall provide all labor, materials, equipment, transportation, and supervision necessary to install new parking lot lighting for building 250 south and east parking lots. The project will include but is not limited to the following principle items. Refer to the project plans for layout and configuration details:
· Installation of seventeen (17) new parking lot lights, single and dual luminaire with photocells
· Installation of bases to support the parking lot lights
· Installation of supply conductors from existing area light supply circuits-contractor to verify adequacy of existing supply circuits
· Installation of ground electrodes and ground bonds
· Poles and fixtures shall be powder coated black or equivalent
The south parking lot is being repaired and reconfigured, and the east parking lot is being repaired under a separate 90 CES contract. Installation of conduits under the paved approaches and between islands is included in the pavement repair contract as shown on the plans.
The contractor shall provide an installation schedule after notice to proceed is given.
The parking lot lights should be configured as shown or similar to the pole and fixture details included with the plans. Note that Pacific Lighting models have been used as annotated, but these have been prone to failure from wind loading. The luminaire detaches from the pole arm. Request a suitable fixture be identified that is not prone to failure and submitted for review by base personnel.
This is an FY09 American Restoration and Recovery Act (ARRA) economic stimulus plan project.
PERFORMANCE PERIOD:
· Site work hours shall be from 7:30 AM to 4:30 PM or as coordinated with the contracting officer. Workdays are Monday through Friday except federal holidays. Saturday and Sunday work may be arranged to minimize the impact of utility cut-over’s and outages.
· The performance period for this project is 180 calendar days after receipt of the Notice to Proceed.
EXISTING CONDITIONS
Field verify all existing conditions, existing construction, dimensions, quantities, other pertinent requirements and suitability for the intended use prior to starting work activities. Determine special requirements or precautions required for items or structures to be renovated, removed, shored, braced or supported.
Do not obstruct or close roadways, sidewalks or exit ways without authorization.
HISTORIC ARTIFACTS
If historic or prehistoric deposits are encountered, stop work at that particular location and notify the Contracting Officer immediately. A Notice to Proceed will be issued only after the find has been evaluated by a qualified archaeologist in accordance with Federal Law. No historic or prehistoric items shall be removed until the evaluation is complete. Items remain the property of the U.S. Government. Historic or prehistoric deposits include all items made or modified by man such as bottles, bricks, foundations, metal items, arrowheads, stone tools, etc. Individual items encountered during construction will not require a work stoppage but must be reported to the Contracting Officer. Notify 90 CES/CEVH before trenching so that trenching may be monitored. If archeological materials are found, work may be stopped until the find can be accessed.
WORK SITE ACCESS
Coordinate access to the Base and Project Facility for personnel and equipment with the Contracting Officer.
STORAGE, STAGING AND PARKING
When space is available at the project site, it may be used for the Contractor's storage, staging and parking areas. When no space is available at the project site or when additional space is required, it will be designated by the Contracting Officer.
No sodded or landscaped areas or exitways shall be used for storage, staging, or parking.
TEMPORARY FUELING FACILITY
It is preferred that a mobile fuel service be used for fueling vehicles and equipment. However, if the contractor desires to use a temporary fueling tank, the following conditions must be met.
Temporary fueling tanks must be vaulted to contain any leaks OR must have a secondary containment basin below the tank built per 90 CES/CEV requirements. Tank must have an alarm that activates when tank has reached 90% full. Tank shall also have a spill catchment box at fuel fill pipe to catch any spills and drain them back into the tank. Maximum tank size is 1,000 gallons. Valve must be locked in closed position except during fueling operations. Tank shall have signage indicating type of fuel and that it is "flammable".
Temporary storage of motor oils and hydraulic fluids must have secondary containment.
Contractor shall be responsible for proper clean-up of any spills. Coordinate with and provide appropriate documentation to 90 CES/CEV.
If used, the contractor shall remove temporary fueling facility upon completion of project and shall sample area to verify site is free of fuels, oils, and any other fluids that were stored at the facility. Provide documentation certifying that the site is clean to 90 CES/CECV.
TEMPORARY UTILITIES
The Government will furnish utilities (water, gas, electricity) to the Contractor when available at no cost from existing points of connections with-in 500 feet of the staging area. All costs of making connections and extensions shall be paid by the Contractor. If no utilities are available with-in 500 feet of the staging area, the contractor shall provide the necessary utilities at no cost to the government.
TEMPORARY SANITARY FACILITIES
Provide portable self-contained sanitary toilets at a location determined by the Contracting Officer or Authorized Representative (COAR)
TEMPORARY FIRE PROTECTION
Provide and maintain temporary fire extinguishers as determined adequate by the Base Fire Department.
FIELD OFFICE AND TELEPHONE
No Field Office is required.
PROJECT SIGN
No project sign is required.
PROJECT COORDINATION
The Contractor is solely responsible for construction means, methods, techniques, sequences, procedures, fabrication processes, safety precautions, safety programs and other necessary precautions during construction.
FIELD ENGINEERING
The General Contractor shall do construction staking and establish horizontal and vertical control elevations for construction including earthwork, paving, and concrete forming.
BARRICADES, FENCING, WARNING SIGNS AND RELATED DEVICES
Erect barricades, safety barriers, barrels, fencing, signs, warning lights, flagging, flag persons and devices as appropriate to control traffic and to warn and protect the workmen, users, occupants and the public. Comply with latest edition of MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES.
All roads, sidewalks, and walkways shall be open during winter exclusion periods.
Building parking lots must accessible. Open trenches which block access must have proper foot bridges constructed.
PROTECTION OF PROPERTY
Protect existing facilities, all materials and equipment to be incorporated therein, completed work, site improvements, trees, landscaping, utilities, public ways and other facilities. Promptly remedy all damage or loss thereto resulting from demolition or construction activities or operations under this contract and restore to equivalent original conditions.
When indicated on the drawings, protect trees to remain with a temporary 6-ft. high fence not less than 5 feet from the trunks.
SPECIAL ALTERATION AND RENOVATION REQUIREMENTS
Cut, move, remove, modify or prepare existing items, surfaces and finishes as necessary for completion of alteration and renovation work. Minimize damage to other work.
Make smooth, even and neat transitions between new and existing work.
Patch, repair, restore or replace disturbed or damaged surfaces and finishes to match original conditions in texture and appearance. When adjacent surfaces and finishes cannot be matched, refinish entire surface to nearest intersection.
Reinstall materials, equipment or items that are disturbed or removed temporarily. Comply with workmanship and other applicable provisions of technical specification sections for comparable new work. Use new screws and other fastening devices.
SPECIAL REQUIREMENTS FOR SITE UTILITIES
Place a color-coded plastic warning tape at least 4" wide within the trench above all buried utility lines. A continuous printed inscription on the tape shall describe the specific utility:
RED Electric.
YELLOW Gas, oil, dangerous material.
ORANGE Communications.
BLUE Water.
GREEN Sewer.
UTILITY SERVICE INTERRUPTIONS AND ROAD CLOSINGS
Notify the Government in writing at least two (2) weeks prior to the interruption of utility or communication services to or within the project site or to facilities used by others. No outage shall exceed four (4) hours. The Government will coordinate the time and duration of all outages with the Using Agency and others.
Roads may be closed one lane at a time with vehicular traffic allowed to pass through the construction area. If an entire street is to be closed notify the Government in writing at least two (2)weeks prior to the closing.
CONFINED SPACE ENTRY
Comply with OSHA (20 CFR 1910.146) and AFOSH STD 91-25 (Nov. 1994) for confined space entry. Manholes, vaults, tunnels and certain pits and other spaces with limited openings for entry/exit or with limited space and not meant for human habitation are considered confined spaces. All are to be considered "permit-required confined spaces" until they have been determined to be "non-permit-required confined spaces".
Prior to entry the Contractor shall notify and coordinate with the Base Fire Dept. and Bioenvironmental Agencies. Assume all emergency rescue responsibilities.
Contractor shall maintain a confined space program without reliance on AF personnel or services except that coordination shall be made with Bioenvironmental Services (BES) to obtain known hazard information and base instituted precautions or procedures. The Contractor shall notify BES of any problem encountered. The contractor permitting process shall provide for entry of necessary AF personnel.
DIGGING PERMITS AND EXCAVATION
A “Digging Permit: is required for all types of excavation, digging, and borings regardless of depth. Requests are submitted via the government Construction Inspector to 90 CES Customer Service in bldg 318. Permit requests should be submitted no more than 14 calendar days prior to the planned excavation date. Permits must be renewed every 30 days. Permits are processed using an Air Force Form 103.
The contractor is responsible for providing the following to the government Contract Inspector when planning an excavation.
1. A drawing of the area of digging.
2. State the purpose of the digging.
3. Provide name, phone number, and organization of the contractor point of contact.
4. Indicate the required start date.
5. Physically mark the actual digging site with white paint or flags. For trench excavation paint or flags at intervals necessary to clearly identify the trench lines is required. For large areas such as parking lots the perimeter of the area to be excavated should be clearly defined with white paint or flags.
Customer Service will hand carry the AF FORM 103 to the appropriate agencies on base for coordination. These agencies include:
| Electric Shop | Communications Squadron |
| Heat Plant | Engineering Flight |
| Utilities Shop | ATT Cable Television |
| Environmental Flight | U.S. WEST Communications |
| Pavements & Equipment Shop | Cheyenne Light, Fuel, and Power |
| Cathodic Protection Shop | Cheyenne Board of Public Utilities |
| EMCS (Alarms) Shop | Grounds Maintenance Quality Assurance |
| Security Police | Evaluator |
| Wing Safety | BNSF (if within Railroad right-of-way) |
Areas, which are clear of utilities, will simply be annotated “Clear” and signed by the locator. Areas, which do have utilities, will be annotated “Utilities in area – call ext. to coordinate an on-site locate with the requestor”, and will be highlighted in fluorescent yellow. The Contract Inspector will coordinate on-site with each shop highlighted and get the locator’s signature. Once all required areas are signed, the Contract Inspector will return the permit to Customer Service, building 318, for approval signature. Once this is accomplished, the permit is valid and excavation may begin. The contractor will not begin excavation until an approved digging permit is received from the Contract Inspector.
Notify the Contract Inspector prior to digging. If ground water is encountered, suspend digging and notify the Contract Inspector.
Exploratory digging by hand or vacuum is required within 5 feet of marked underground utilities. Hand digging or vacuum excavation is required when crossing underground utilities. If digging is required parallel and within 10 feet of an existing utility, exploratory digging must be performed by hand or vacuum excavation until the location of the utility is physically confirmed. After the location is physically confirmed digging may be performed by machine.
ENVIRONMENTAL COMPLIANCE REQUIREMENTS
The Contractor shall comply, and their subcontractors comply, with the most stringent environmental federal, state, and local laws and regulations; and Air Force policies, instructions, and plans.
The Contractor shall comply with all environmental regulations pertaining to all activities performed on WAFB that are subject to federal, state, and local laws and regulations including, but not limited to: National Environmental Policy Act (NEPA); Endangered Species Act; National Historic Preservation Act (NHPA); Archaeological Resources Protection Act (ARPA); Resource Conservation and Recovery Act (RCRA); Hazardous and Solid Waste Amendments; Pollution Prevention Act; Clean Water Act (CWA); Clean Air Act (CAA); Safe Drinking Water Act; Emergency Planning and Community Right to Know Act (EPCRA); and Toxic Substances Control Act (TSCA). The federal Government is not exempt from compliance with environmental regulations.
The Contractor shall coordinate all environmental regulatory agency environmental issues through the 90th Civil Engineer Squadron, Environmental Management Flight, 90 CES/CEV. The 90 CES/CEV office is the single point of contact for all environmental regulatory agency issues for activities on F. E. Warren Air Force Base (WAFB).
The Contractor shall comply with all environmental permit conditions and consultation requirements. The agencies typically involved in WAFB activities include, but not limited to: U.S. Fish & Wildlife Service (USFWS); State Historic Preservation Officer (SHPO); Regional Water Quality Control Board (RWQCB) and Certified Unified Program Agency (CUPA).
REFERENCES
The publications listed below form a part of this specification to the extent referenced. All references listed in these specifications are intended to be the current version or edition, unless specifically identified otherwise. The Contractor shall conform to the Occupational Safety & Health Act, Environmental Protection Agency, Wyoming Dept. of Environmental Quality, U.S. Air Force and all other Federal, State and Local environmental regulatory requirements.
29 CFR Occupational Safety and Health Administration Code of Federal Regulations
40 CFR Environmental Protection Agency Code of Federal Regulations
49 CFR Department of Transportation Code of Federal Regulations
90th CES/CEV Affirmative Procurement Plan
90th CES/CEV Integrated Hazardous Material Contingency Plan
90th CES/CEV Hazardous Material Management Plan
AFl 32-7080 Air Force Instruction (Ozone Depleting Chemicals)
PERMITS AND FEES
No separate payment will be made for work covered under this section. The Contractor shall be responsible for payment of fees associated with environmental permits, application, and/or notices obtained by the Contractor. All costs associated with this section shall be included in the contract price. The Contractor shall be responsible for payment of all fines/fees for violation or non-compliance with Federal, State, Regional and local laws and regulations.
The Contractor shall be responsible for obtaining and complying with all environmental permits and commitments required by Federal, State, regional, and local environmental laws and regulations.
AIR QUALITY
Equipment operation, activities, or processes performed by the Contractor shall be in accordance with all Federal and State air emission and performance laws and standards.
The Contractor is not allowed to burn material on base.
Particulates - The Contractor shall not operate a construction site or demolition project unless reasonable precautions are taken to control emissions of particulate matter. Such emissions of airborne particulate matter shall not exceed 20% opacity as defined in 40 CFR 60 Appendix A.
Sound Intrusions - The Contractor shall keep construction activities under surveillance and control to minimize environment damage by noise. The Contractor shall comply with the provisions of the State of Wyoming rules.
Ozone Depleting Chemicals (ODCs)
The Contractor shall ensure activities performed under this contract are in compliance with the Air Force Policy on ODCs. The Contractor shall not purchase, use, nor specify the use of any Class I ODC in the production, design, or maintenance of the end item. Class II ODCs may be used or specified only with the written approval of the . ODCs are identified and classified in Air Force Instruction (AFl 32-7080).
WATER RESOURCES AND STORM WATER DISCHARGE
The Contractor shall monitor construction activities to prevent pollution of surface and ground waters. Toxic or hazardous chemicals shall not be applied to soil or vegetation unless otherwise indicated. The Contractor shall monitor all water areas affected by construction activities. For construction activities immediately adjacent to impaired surface waters, the Contractor shall be capable of quantifying sediment or pollutant loading to that surface water when required by State or Federally issued Clean Water Act permits.
The Contractor shall not discharge any contaminated materials into the storm drain system on Base. EPA authorizes the following non-storm water discharges: fire fighting activities; fire hydrant flushing; potable water sources; irrigation drainage; lawn watering; routine building wash-down without detergents; pavement wash-waters where spills/leaks of toxic or hazardous materials have not occurred and where detergents are not used; air conditioning condensate; springs; uncontaminated groundwater; and foundation/footing drains where flows are not contaminated with process materials such as hydrocarbons/solvents.
Sanitary Sewer - The Contractor shall not dump any restricted materials down the sanitary sewer or wastewater disposal system without approval of the Air Force. All discharges to the sewer shall meet Federal, State, and Local regulatory requirements and shall meet the permit requirements limiting FEW AFB discharges. The base sewer discharge is tested weekly by the City of Cheyenne for conformance requirements.
Restricted waste water materials include those that create a fire or explosion hazard; are toxic or poisonous; waters or wastes having a pH lower than 5.5 or higher than 9.0; solid or viscous substances that can obstruct the sewer flow; interfere with the biological activity of a treatment plant; inhibit biological activity by increasing the temperature; any fats, wax, grease, or oils in excess of 100 mg/I, total petroleum hydrocarbons in excess of 25 mg/I, noxious or malodorous liquids; contain metals in excess of iron-0.03 rog/I, chromium-5.676 mg/I, copper-4.985 mg/I, cyanide-0.505 mg/I, zinc-1.019 mg/I, arsenic-0.462 mg/I, cadmium-3.551 mg/I, lead-0.946 mg/I, mercury-0.028 mg/I, nickel-4.782 mg/I or silver-0.531 mg/I, FEW AFB's industrial permit allowable limits; contain phenols or dyes; are radioactive; that contain over 100 lbs per day of total suspended solids (TSS) or five day biochemical oxygen demand (BOD) or cause the Base waste water discharge to exceed 200 mg/I BOD or 250 mg/I TSS.
For discharge of ground water, the Contractor shall [surface discharge in accordance with the requirements of the NPDES or State Storm Water Discharges From Construction Sites permit.]
Storm Water Discharge Permit
Construction Activities-Storm Water Discharge Permit – WYPDES (Wyoming Pollutant Discharge Elimination System) General Permit for Storm Water Discharges Associated with Construction Activity is required for construction activity in which clearing, grading and excavation will result in disturbance of 1 acre or more of land.
1. For construction projects that disturb at least 1 acre but less than 5 acres, the contractor shall obtain and comply with all requirements of a general small construction Wyoming Pollution Discharge Elimination System (WYPDES) permit (WYR10-A000). To obtain this permit, a site specific Storm Water Pollution Prevention Plan (SWPPP) shall be signed by an approved company official (as per Part 11.7 of the General Permit) and submitted to Civil Engineer Squadron Environmental Flight (90 CES/CEV) 30 days prior to construction start date for approval. All Best Management Practices (BMPs) listed in the SWPPP shall be installed prior to construction. The contractor shall comply with all permit requirements until the site has reached final stabilization, which is determined by 90 CES/CEV, which includes, but is not exclusive to the following:
The Storm Water Pollution Prevention Plan (SWPPP) plan must meet the basic requirements provided in Part 8 of the General Permit.
The SWPPP must be maintained on the construction site as per Part 8.5 of the General Permit.
The Contractor shall perform and document inspections as per Part 9 of the General Permit until site has reached final stabilization.
Upon final stabilization of site, the contractor shall submit copies of all inspection logs to 90 CES/CEV.
2. For construction projects that disturb five or more acres, the contractor shall obtain and comply with all the requirements for the general large construction WYPDES permit (WYR10-0000). Forty (40) days prior to construction start date, the contractor shall submit a Notice of Intent (NOI) and the site specific SWPPP signed by an approved company official (as per Part VII G of the General Permit) to 90 CES/CEV for approval. The contractor shall submit the approved NOI to Wyoming Department of Environmental Quality (WDEQ) at least 30 days prior to construction start date. The contractor shall submit a copy of the WDEQ signed permit to 90 CES/CEV. All BMPs listed in the SWPPP shall be installed prior to construction. The contractor shall comply with all permit requirements until the permit has officially been terminated, which includes, but is not exclusive to the following:
The SWPPP must meet the basic requirements of the SWPPP provided in Part IV of the General Permit.
The SWPPP must be maintained on the construction site as per Part IV E. of the General Permit.
During construction, the Contractor shall perform inspections as outlined in Part III of the General Permit.
The contractor shall pay WDEQ all fees associated with the permit.
After the site has achieved final stabilization, as determined by 90 CES/CEV, the Contractor shall submit a Notice of Termination (NOT) to 90 CES/CEV and WDEQ; and the Contractor shall submit copies of all inspection logs to 90 CES/CEV.
The Contractor should reference the Wyoming Department of Environmental Quality's website at http://deq.state.wy.us/wqd/index.asp?pageid=125 for forms, instructions, SWPPP information, and other guidelines for complying with Wyoming storm water requirements.
EROSION, SEDIMENT CONTROLS, AND WETLANDS
Wetlands - The Contractor shall not enter, disturb, destroy, place fill into, or allow discharge of contaminants into any wetlands except as specifically authorized herein. The Contractor shall be responsible for the protection of wetlands on F. E. Warren AFB. Authorization to enter specific wetlands identified shall not relieve the Contractor from any obligation to protect other wetlands within, adjacent to, or in the vicinity of the construction site and associated boundaries. Maps showing locations of wetlands within F. E. Warren AFB can be obtained from the 90 CES/CEV.
The Contractor shall be responsible for providing erosion and sediment control measures in accordance with Federal, State, and local laws and regulations. The erosion and sediment controls selected and maintained by the Contractor shall be such that water quality standards are not violated as a result of the Contractor's construction activities. The area of bare soil exposed at any one time by construction operations should be kept to a minimum. The Contractor shall construct or install temporary and permanent erosion and sediment control best management practices (BMPs). BMPs may include, but not be limited to, vegetation cover, stream bank stabilization, slope stabilization, silt fences, construction of terraces, interceptor channels, sediment traps, inlet and outfall protection, diversion channels, and sedimentation basins. The Contractor's best management practices shall also be in accordance with the Base Storm Water Pollution Prevention Plan (SWPPP), which may be reviewed at the F. E. Warren AFB Environmental Office. Any temporary measures shall be removed after the area has been stabilized.
NUCLEAR DEVICES AND RADIOACTIVE MATERIALS
Comply with AFI 40-201 (July 1994), Managing Radioactive Materials in the USAF, regarding posting Notices to Workers, proper use of equipment and other requirements therein.
Submit written request on company letter head to Base Environmental Engineering Services (90 AMS / SGPB, Attention: Base Radiation Protection Officer) prior to bringing onto the Base or using any nuclear devices or radioactive materials. Include description, location and estimated dates of proposed activities; applicable specification pages; copy of current NRC or Agreement State license; name, address and telephone number of responsible local representative and radiation safety officer (RSO) named on the license; and an acknowledgment that the RSO can make periodic checks to ensure Contractor compliance and suspend operations deemed unsafe.
WELDING, CUTTING AND BRAZING PERMITS
A permit is required for any welding, torch cutting, sweating, brazing or similar operation using an open flame. Make application on AF Form 592 through the Base Fire Department (90 CES / CEFT), Bldg. 324. Permits must be renewed each month. Fire extinguishers must be on hand during these operations.
Comply with AFOSH STD 91-25 (Nov. 1994).
SPILL PREVENTION AND RESPONSE
Develop a plan for spill prevention and for spill detection, reporting, containment, cleanup and disposal. The Base Fire Department and the Environmental Flight shall be immediatly notified when a spill occurs so proper reporting and cleanup can be accomplished. A spill resulting in generating a hazardous waste must be properly disposed. Manifesting of hazardous waste must be signed by a proper authority in the Environmental Flight IAW Federal State and local laws addressing EPA, DOT, and OSHA requirements.All workers shall be familiar with this plan.
Submit copy of this plan to the Base Contracting Officer on AF Form 3000 for approval. Copies of all disposal manifests (hazardous and non-hazardous) shall be returned to Environmental in 35 days.
DISPOSAL AND CLEANUP
Remove all debris, waste and surplus materials from the immediate work areas each day and from the premises at suitable intervals. Disposal shall be at an off-Base location at an established landfill or other site approved for the type of material being removed. Burning or burial at the project site are not acceptable disposal methods.
Upon completion of the project, leave site and streets in a clean, sanitary, odor-free, acceptable condition, ready for operation .
Hose down and broom all concrete slabs, walks, and paved areas.
Rake clean other exterior ground surfaces.
SYSTEM DEMONSTRATION AND TRAINING
Each Installer of equipment and systems shall meet with Government personnel (Project Inspector, Engineer, User and Maintenance Personnel) and provide complete instructions and demonstrations regarding proper operation including start-up and shut-down, safety procedures, adjustments and maintenance. This service shall be provided by manufacturer's representatives if installers lack sufficient information or experience.
RECORD DRAWINGS
Upon completion, submit to the Contracting Officer a complete set of clean, undamaged record (as-built) drawings. Mark a set of the contract blueprints in a neat orderly manner as the work progress, showing changes in installation or project conditions including those changes resulting from amendments and contract modifications. Use waterproof red pen or pencil. Give particular attention to concealed elements that would be difficult to measure and record at a later date. Give dimensions to fixed points. As-Builts shall include civil, architectural, structural, mechanical and electrical actual conditions.
MATERIAL AND EQUIPMENT DISPOSAL
All equipment and material removed by the Contractor shall become the property of the Contractor and be disposed of off base. Oil Filled Switches shall be disposed in accordance with IAW EPA guidelines, PCB sample test reports are available from the Base Civil Engineer.
TRENCHING AND TUNNELING REQUIRMENTS
Avoid trenching near trees to minimize root damage. Where possible, stay beyond the drip line of trees but in no case shall trenching be closer than 15 ft. from center of large trees (36” diameter or larger measured at 4 ft. above the ground), 12 ft. from 24” to 36” diameter trees, 10 ft. from 18” to 24” diameter trees, 8 ft. from 12” to 18” diameter trees, and 6 ft. from trees under 12” in diameter.
In general, stop trenching when roots 2 inches or larger are encountered. When roots 2 inches or larger are accidentally severed, make a sharp cut with a hand saw a couple of inches beyond the ragged end.
If necessary, tunneling at least 24 inches below the surface and away from the trunk as far as possible shall be used instead of trenching in order to comply with the above requirements.
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