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RESOLUTION NO. 84 49
OF THE
TRUCKEE DONNER PUBLIC UTILITY DISTRICT
APPROVING SPECIFICATIONS AND CALLING FOR
.� TREE TRIMMING PROPOSALS
WHEREAS, it is the desire of the District to obtain qualified per-
sonnel and operationally reliable equipment on a contract basis to trim,
cut and dispose of trees and brush on power line rights-of-way and along
and under the District's distribution and transmission lines;
NOW, THEREFORE, BE IT RESOLVED by the Board of Directors of the
Truckee Donner Public Utility District as follows:
1. That the specifications for tree work attached hereto are
hereby approved.
2. That the President of the Board of Directors is hereby
directed to issue a call for proposals based on the attached
specifications.
3. That the date and time established for the bid opening is
, 1984, at 4:00 P.M.
PASSED AND ADOPTED by the Board of Directors of the Truckee Donner
Public Utility District at a regular meeting thereof duly called and held
in the District on the 6th day of August 1984, by the fol-
lowing roll call vote:
AYES: Cooley, Corbett, Duffy, Hamilton and Maass.
NOES: None.
ABSENT: None.
TRUCKEE DONNER PUBLIC UTILITY DISTRICT
By N
-TAifies A. Maass, President
ATTEST:
Susan M. Craig, Deputy Distri t Clerk
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SPECIFICATIONS
TREE WORK
1. SCOPE OF BID
.� The purpose of this specification is to obtain qualified personnel and op-
erationally reliable equipment on a contract basis to trim, cut and dispose
of trees and brush on power line rights-of-way and along and under the Dis-
trict's distribution and transmission lines, as directed by the District's
designated representative.
2. LOCATION OF WORK
All work will be at various locations throughtout the Truckee Donner Public
Utility District.
3. CREW SIZE AND EQUIPMENT
For the purpose of evaluation, a crew shall consist of : A Foreman, a Tree
Trimmer, and a Head Groundman (Chipperman) ; and their equipment shall include
an operationally reliable lift truck, constructed and completely equipped for
tree trimming, with a minimum ground-to basket height of fifty feet. Aerial
lift trucks shall have over-center type upper booms with 360 degrees contin-
uous rotation. This truck shall be equipped with one gasoline-powered chain
saw.
Also included shall be an operationally reliable dump-type, chip haul truck
which is to tow an operationally reliable chipper. This chip haul (dump type)
truck and chipper shall be considered as one unit and shall be billed only for
actual hours used on the job as determined by the District's authorized repre-
sentative. _
The Contractor shall provide sufficient crews to meet the District's require-
ments. Contractor will be provided five working days' notice of the District's
need to utilize additional crews. Crew structure shall be as authorized by the
District's representative.
The Contractor shall provide Flagmen as required to meet existing laws.
4. CUSTOMER RELATIONS
It is understood that the Contractor does not represent the District and has
no authority to obligate the District for any payment or benefit of any kind
to any person.
5. BIDDING AND QUANTITY OF WORK
The total amount of work to be done under this contract shall be as noted in
the Special Conditions to this contract. No work may be done under this con-
tract after the termination date established in the Special Conditions.
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The labor and equipment costs which make up the Total for Proposal Comparison
and the alternate personnel and alternate equipment costs shall include: (1)
All mobilization and demobilization costs of the Contractor's plant, forces
and equipment including mobilization and demobilization required by suspen-
sions of work; (2) all operational and labor costs for fuel and fueling, oil,
grease and maintenance upkeep and repairs to the equipment; (3) all taxes
�^ (except sales tax) , deductions, overhead and profit. In most instances there
will be no sales tax; however, sales tax will be paid on such work as required.
The Contractor must provide separate invoices for all taxable work.
Approval by the District's representative will be required for any daily pay-
ment in excess of eight hours.
Except for the payment of the prevailing wages and working condition benefits as
set forth in the General Conditions and such other specific provisions set forth
in the contract documents which apply to the work, the Contractor shall be re-
sponsible for following the working rules of his agreement with his employees
and his unit prices shall so provide.
Bidders shall furnish the following information:
5. 1 Detailed description of manlift truck to include -
a) Manufacturer, model, year, and size of truck
b) Manufacturer and type of other equipment
c) Maximum height from ground to bottom of basket
d) Maximum reach from ground with air power trim saw
e) Air pressure carried?
f) Outriggers required?
g) Type of power for ladder and compressor operation
(P.T.O.? Separate engine?)
5.2 Chip haul (dump type) truck and chipper -
a) Manufacturer, make, year, and size of truck
b) Capacity of chipper bed
c) Hydraulic dump?
d) Manufacturer, model, year, and size of chipper
5.3 Other equipment furnished on the job
5.4 Name and experience of proposed Foremen and Tree Trimmers
5.5 List of other utility companies where now operating similar
crews and equipment
5.6 Name and experience of Supervisor who will be responsible for
crews under this contract
5.7 Date Contractor will be available to start work
5.8 List of other information which may be pertinent
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aye
6. GENERAL
All tree work shall be done so as to obtain maximum clearance with due regard
to current and future tree health and symmetry, and in conformity with permis-
sions obtained.
It is understood that the electric circuits of the District are to continue
in normal operation during this work, and the Contractor is to provide and use
all protective equipment necessary for protection of his employees and to guard
against interfering with the normal operations of said circuits. Contractor
agrees to secure from the District information as to the nature of the cir-
cuits involved in all cases before work is commenced.
All vehicles used under this work shall be equipped and marked to meet all
rules and regulations of the State of California, and all personnel shall be
trained and qualified as may be required by the State of California. All
work and equipment shall meet all OSHA requirements.
The Contractor's supervising representative shall become acquainted with the
District's work practices and procedures prior to commencing work.
All brush, chips and cut material shall be disposed of by hauling away and
dumping in areas designated or appropriate for disposal. The work area must
be left clear of any debris.
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T R E E T R I M M I N G G U I D E L I N E S
1.o TRIMMING AND REMOVAL GUIDELINES
The two main purposes for trimming trees are to deter someone climbing the
�^ tree and contacting high voltage lines, and to prevent tree/conductor con-
tact that may initiate forest fires or affect service reliability.
This must be kept in mind at all times when considering whether a tree
requires trimming and the type of trimming necessary.
i
1.1 Minimum Clearance Guidelines
The following are the minimum clearance guidelines that should be main-
tained between the conductor or energized part and all portions of the
tree.
Remember, the tree should be sufficiently trimmed beyond these clearan-
ces to not require additional cutting for at least two years.
Deciduous trees generally grow faster and require more trimming than
evergreens.
a . Radial clearance for any secondary conductor energized less than
600 volts to ground or bare neutral conductor . . . . 2 feet.
b. Radial clearance for any conductor energized line to line voltage
of 2,400 volts but less than 55.,000 volts . . . . 4 feet.
C. Radial clearance for any conductor energized line to line voltage
of 55,000 volts but less than 130,000 volts . . . . 6 feet.
d. Radial clearance for any conductor energized line to line voltage
of 130,000 volts but less than 250,000 volts . . . . 10 feet.
e. Radial clearance for any conductor energized line to line voltage
greater than 250;000 volts . . . . 15 feet.
Any exceptions to these clearance guidelines must be approved by the
authorized TDPUID supervisor.
1.2 Trees Under Line - Remove or Top
Trees directly under the line or whose trunks are within the following
distances from the outermost conductor should be removed or topped:
4 feet (2,400 volts to less than 55,000 volts)
6 feet (55,000 volts to less than 130,000 volts)
10 feet (130,000 volts to less than 250,000 volts)
15 feet (greater than 250,000 volts)
�877
.�- Small young trees within the above boundaries should be removed if
practicable.
Trees that cannot be removed should be topped, not side trimmed, to
the clearances specified in the guidelines.
Whenever possible, trees should be trimmed to maintain their charac-
teristic shape.
1.3 Trees Away from Line - Side Trim
Trees further away from the line than the boundaries shown in the
guidelines should be side trimmed to the guideline specifications.
Consideration should -be given to removing limbs above the conductor
to deter someone falling into the line. Flexible limbs that some-
one might swing on or that may otherwise come in contact with the
line should also be removed.
1.4 Trimming to Deter Climbing
Any tree that presents conductor/contact safety hazards may require
removal of the limbs from at least ten feet above the ground to de-
ter climbing.
Watch for buildings or walls that might provide access into the
tree. Remove all necessary limbs to deter climbing in these cases.
1.5 Dead Trees and Limbs
Dead or diseased trees and limbs that may break and fall into the
line should be removed.
1.6 Pruning Compound
Pruning compound shall be used to retard sucker growth, deter in-
sects, and prevent infections when required.
r is TOP TREE IF MAIN TRUNK
IS WITHIN RADIAL CLEARANCE
�!��-�►/�� RADIAL CLEARANCE
�,•• 1 • SI , TRIM SUFFICIENTLY
OEYOND CLEARANCES
FOR AT LEAST 2 YEARS
GROWTH
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BEFORE AFTER
TREES UNDER LINES - TOP OR REMOVE
"D? TO C-EARANCE
REMOVE IF
PRAcrICAOLE
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r
. \
SMALL YOUNG
L<' TREES
DEFORE AFTER
REMOVE FLEXIBLE AND
_ DE AO LIMBS ABOVE CIFMANCC
ZONE THAT MAY CONTACT LINE.,
OAANCNE3
i REMOVED -
f TO TREE
` I TRUNK.
i
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1
I
TRUNK 013TANCE
GREATER THAN
RADIAL DIST-
ANCE
BEFORE AFTER
TREES AWAY FROM LINE - SIDE TRIM
j I MAINTAIN RADIAL DISTANCE
REMOVE ALL BRANCHES
1 THAT MAY PROVIDE
ACCESS INTO TREE
1
i 1 /
REMOVE ALL
BRANCHES 10 I
IOr FROM GAO.
TO DETER
CU USING.
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BEFORE AFTER
/ POWER LINES SURROUNDED BY
A LARGE NUMBER OF TREES .
i �►
MMN TRUNK M WITHIN I i
CLEARANCE ZONE
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REMOVE ALL
DRANCHES 10 REMOVE All BRANCHES
TO DETER I IN RADIAL CLEARANCE
CLIMBING. -
TREE TRUNK MUST FI'!
To STRONG ENOUGH
TO J`(
RESIST SWAYING
INTO LINES
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END VIEW DETAIL
EXCEPTION FOR EXISTING TREES AND FACILITIES
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F
RUCTIONS FOR OUTLYING AREAS
eas away from man's influence (deserts, forests, canyons, etc. ) , it is
tial that as little flora as possible be disturbed. Leave ground cover
ched, except when "feathering" greatly improves appearances, or when
ing around poles to prevent fires.
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�~^ � ^ter�y....v
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Feathered edges of R/W.
,- On hillsides and in canyons, remove trees which might fall or slide into the
line, a pole, or a structure. Only the uphill side shall be disturbed.
Leave trees and brush on the downhill side; they will not inter-fere with the
line. It is especially important that all brush and ground cover be left on
the uphill side of poles and structures. Removal could result in erosion,
which is to be avoided.
3.0 INSTRUCTIONS FOR TRIMMING AROUND TRANSMISSION LINES
In construction of large transmission corridors, there are several methods
for disguising the existence of the corridor. When a corridor crosses a
well defined boundary between timber and clearing or between timber and a
road, only those trees which directly interfere with the structures or lines
should be tr=-nmed or removed. Brush, shrubs, saplings, and grass should be
left in the corridor opening. In addition, access roads should be cut
diagonally to the direction of the corridor in order to prevent the
appearance of a long swath through the trees.
Cod
AA
Transmission corridor crossing a road.
AL
Channelized transmission corridor - avoid.
The "channeled effects" should be avoided; instead, the right-of-way should
follow the terrain. On a flat, the corridor should reach its greatest
width, while in steeper areas it should become more narrow. As a general
rule, the corridor should not stay the same width for more than a few
hundred feet; curving or scalloping the edges is much less unsightly.
n� r)
Curved and scalloped corridor - preferred.
a�4'
4.0 MINIMUM WORKING DISTANCE
During the tree trimming process, all safe minimum working distances for
energized conductors shall be observed
Voltage Range
Phase to Phase * Minimum Working
Kilovolt Distance
2. 1 to 15 2 ft.
15.1 to 35 2 ft. 4 in.
35.1 to 46 2 ft. 6 in.
46.1 to 72.5 3 ft.
72.6 to 121 3 ft. 4 in.
138 to 145 3 ft. 6 in.
161 to 169 3 ft. 8 in.
230 to 242 5 ft.
345 to 362 7 ft.
500 to 552 15 ft.
*No conductive object, except with approved devices shall be taken any
closer to unprotected energized circuits than the distance shown in the
table.