Specifications and Drawings for Underground Electric Distribution

AGENCY:

Rural Utilities Service, USDA.

ACTION:

Final rule.

SUMMARY:

The Rural Utilities Service (RUS) is revising its regulations on Specifications and Drawings for Underground Electric Distribution, RUS Bulletin 50-6. This bulletin is currently incorporated by reference in RUS regulations and, will continue to be incorporated by reference. This revision is necessary to provide RUS electric borrowers with the latest specifications for constructing their rural underground electric distribution systems using state-of-art materials, equipment, and construction methods. RUS is renumbering and reformating the revised bulletin in accordance with the agency's new publications and directives system.

DATES:

Effective Date: June 26, 2000.

Incorporation by Reference: IBR approved by the Director, Office of the Federal Register, June 26, 2000.

FOR FURTHER INFORMATION CONTACT:

Mr. Trung V. Hiu, Electrical Engineer, Distribution Branch, Electric Staff Division, Rural Utilities Service, U.S. Department of Agriculture, 1400 Independence Avenue, SW, STOP 1569, Washington, DC 20250-1569. Telephone: (202) 720-1877. Fax: (202) 720-7491.

SUPPLEMENTARY INFORMATION:

Executive Order 12866

This rule has been determined to be not significant for purposes of Executive Order 12866 and, therefore, has not been reviewed by Office of Management and Budget (OMB).

Executive Order 12372

This rule is excluded from the scope of Executive Order 12372, Intergovernmental Consultation, which may require consultation with State and local officials. See the final rule related notice entitled “Department Programs and Activities Excluded from Executive Order 12372” (50 FR 47034).

Executive Order 12988

This rule has been reviewed under Executive Order 12988, Civil Justice Reform. RUS has determined that this rule meets the applicable standards provided in section 3 of the Executive Order. In accordance with the Executive Order and the rule: (1) All State and local laws and regulations that are in conflict with this rule will be preempted; (2) no retroactive effect will be given to this rule; and (3) in accordance with § 212(e) of the Department of Agriculture Reorganization Act of 1994 (7 U.S.C. 6912(e)), administrative appeal procedures, if any, are required, must be exhausted prior to initiating litigation against the Department or its agencies.

Regulatory Flexibility Act Certification

The Administrator of RUS has determined that a rule relating to the RUS electric loan program is not a rule as defined in the Regulatory Flexibility Act (5 U.S.C. 601 et seq.) and, therefore, the Regulatory Flexibility Act does not apply to this rule. RUS borrowers, as a result of obtaining Federal financing, receive economic benefits that exceed any direct economic costs associated with complying with RUS regulations and requirements.

Information Collection and Recordkeeping Requirements

This rule contains no reporting or recordkeeping provisions requiring Office of Management and Budget (OMB) approval under the Paperwork Reduction Act of 1995 (44 U.S.C. Chapter 35).

National Environmental Policy Act Certification

The Administrator of RUS has determined that this rule will not significantly affect the quality of the human environment as defined by the National Environmental Policy Act of 1969 (42 U.S.C. 4321 et seq.) Therefore, this action does not require an environmental impact statement or assessment.

Catalog of Federal Domestic Assistance

The program described by this rule is listed in the Catalog of Federal Domestic Assistance Programs under No. 10.850, Rural Electrification Loans and Loan Guarantees. This catalog is available on a subscription basis from the Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402-9325. Telephone: (202) 512-1800.

Unfunded Mandates

This final rule contains no Federal mandates (under the regulatory provision of Title II of the Unfunded Mandates Reform Act of 1995) for State, local, and tribal governments or the private sector. Thus, this rule is not subject to the requirements of section 202 and 205 of the Unfunded Mandates Reform Act of 1995.

Background

Pursuant to the Rural Electrification Act of 1936 (7 U.S.C. 901 et seq.), the Rural Utilities Service (RUS) is amending 7 CFR Chapter XVII, Part 1728, Electric Standards and Specification for Materials and Construction, by revising RUS Bulletin 50-6 (D-806), Specification and Drawings for Underground Electric Distribution. This revised bulletin is renumbered as RUS Bulletin 1728F-806. RUS maintains a system of bulletins that contains construction standards and specifications for materials and equipment which must be complied with when system facilities are constructed by RUS electric and telecommunications borrowers in accordance with the RUS loan contract. These standards and specifications contain standard construction units, material, and equipment units commonly used in RUS electric and telecommunications borrowers' systems.

RUS Bulletin 50-6 provides standard underground electric distribution construction drawings and specifications of 12.5/7.2 kV and 24.9/14.4 kV underground electric distribution lines. RUS is changing the bulletin number from RUS Bulletin 50-6 to RUS Bulletin 1728F-806. The change in the bulletin number and reformatting is necessary to conform to RUS new publications and directives system. This rule incorporates the bulletin by reference in 7 CFR part 1728.97.

Major changes in the bulletin are described below:

(1) Two new drawings, UC2-1 and UC2-2, have been added as alternative construction to existing drawing UC2.

(2) RUS has determined that the URD INSPECTION FORM and 23 drawings are no longer practical. Therefore, RUS has removed the following drawings: UC3, UC4, UG9A, UG23, UM3-47, UM3-48, UM8-3, UM12-1, UM12-2, UM-26, UM50, UX8 through UX10, and UX12 through UX26.

(3) Some of the specifications cited in the bulletin preface have been altered to comply with the latest codes and regulations and to improve field construction.

(4) The titles of the drawings in the Index of Drawings have been modified to have better descriptions.

Approximately 60 drawings have been revised with one or more of the following changes:

(1) Clearance distance B has been changed to be the distance between open vertical conductors (outer edge nearest to pole) and pole center in accordance to the latest codes.

(2) A B MINIMUM table has been added to appropriate drawings to show proper clearances corresponding to different voltages.

(3) Ground rods have been redrawn to proper grade.

(4) The installation of CAUTION, WARNING, and DANGER signs has been changed to meet the latest codes.

(5) In the material tables, item U hw, CAUTION sign, has been changed to WARNING sign.

(6) In the material tables, item U hp, elbow termination, has been added.

(7) Ground wires between ground rods and connectors have been redrawn as dotted lines.

(8) In boxes labeled B MINIMUM, the v in kv has been capitalized.

(9) Some notes below the DESIGNATE AS headings have been deleted where appropriate.

(10) In the material tables, (load break type) has been removed from item af, cutout descriptions.

(11) Several conductor routes have been redrawn for easier construction and increased performance.

(12) Devices, such as surge arresters, have been redrawn and relocated to reflect the improved designs and to meet the latest construction practices and safety codes.

(13) Crossarms, penta-head bolts, one-line diagrams, grounding pads, and pin insulators have been added to certain drawings where appropriate.

(14) Blowups have been added to several drawings to emphasize details.

(15) The notes on some drawings have been revised to remove ambiguity and to meet the latest safety codes and construction standards.

On April 8, 1998, RUS published a proposed rule in the Federal Register, at 63 FR 17128. RUS received numerous comments from several cooperatives and interested individuals. The followings are the submitted comments and RUS responses:

(1) Set all pad-mounted equipment on concrete vaults. The reinforcing steel in the base is tied to the ground rod. Tests have shown this scheme to provide a very good ground.

Response: RUS disagrees as this practice may not be practical and may not significantly improve grounding in most cases.

(2) Section 7.4: Requires “mechanical tamp for only 36 inches from major units”—suggests no tamping requirement for the remainder of the trench. Is that the intent?

Response: No. The 36 inches (0.9 meters) is mandatory and is a minimum requirement.

(3) Section 7.5: Does the term “hole” refer to ground sleeve, or vault? Should RUS change this term?

Response: Section 7.5 has been removed. This practice is not recommended by RUS.

(4) Section 11.2: The “not more than one splice per 2,000 feet” is not practical if conduits and ground sleeves are involved. Splice location markings can be helpful, but not needed as a “must”.

Response: RUS allows the borrower the option to specify. RUS intention is to limit the number of splices of multi (“scrap”) cables.

(5) Section 12.1: Would RUS consider reseal of the jacket?

Response: As a precaution and to maximize reliability, RUS borrowers must use heat or cold shrink sleeves accepted by RUS (Refer to items U hf and U hy in RUS Information Publication 202-1, List of Materials Acceptable for Use on Systems of RUS Electrification Borrowers).

(6) Section 14.4: RUS may want to consider dead front treatment of this type transformer.

Response: RUS does not accept enclosures such as sectionalizers and transformers unless they are of the dead front design.

(7) Section 25.1: Is it the intention to require testing or to recommend testing that would be helpful?

Response: Bulletin 1728F-806 requires that conductor continuity tests be conducted while it recommends that borrowers perform the high potential test. The term “shall” has been changed to “should” for the high potential test in section 25.1.b.

(8) Drawing UC2-2: Cutouts placed on the opposite side of the crossarm would not expel fuse material on the terminations.

Response: RUS agrees and has made the modifications to accommodate the suggested comment.

(9) Drawing UC5 and UC6: Clarify underground source/or reverse switch. Also, jumpers from switch to overhead lines would not route to the pole like a ground wire. End view of equipment bracket needs to clarify separate phase connections; may need to exaggerate center phase offset.

Response: The center primary conductor has been redrawn to depict a primary conductor not a ground wire. The devices are in line when seen from the sideview.

(10) Drawing UG7: Position of primary bushings not typical of transformer supplied.

Response: RUS is more concerned with detailing how the electrical connections should be completed. The philosophy of electrical connections is important because the bushing layout design may change from time to time. The drawing shown depicts an ANSI Type I transformer. As a result of this connection, the neutral has been moved to the bottom bushing.

(11) Drawings UJ1 and UJ2: Dead front requirement is not clear.

Response: These drawings apply to secondary connector blocks. Dead front construction does not apply here. However, to minimize chances for confusion, a note stating “insulated cover removed” has been added to the drawings.

(12) Drawing UK6: Pentahead bolts on a below grade enclosure would seem unnecessary.

Response: Public access and safety concerns for accessible underground facilities are no different than above grade construction.

(13) Sections 10 and 11 Method of Calculating Minimum Conduit Size and Installation in Conduit or Duct: Should RUS provide an explanation of why these two sections were deleted and where a borrower can find information on the installation of wire in conduit?

Response: The previous RUS published method of calculating conduit size is not the best available method. RUS recommends that borrowers contact cable and conduit manufacturers for design and installation instructions.

(14) Drawing UG9A: Should this drawing be retained. It may be useful, as a reference, when retiring this unit from the field.

Response: This construction standard is no longer recommended and has been removed from Bulletin 1728F-806. RUS suggests borrowers refer to RUS Bulletin 1767B-2 for reference of retirement units.

(15) In general, the print size should be increased, especially item letters attached to drawings. It's easy to confuse e and c or a and o.

Response: The font sizes have been increased.

(16) On all terminal drawings, delete reference to parallel arresters. Those haven't been used since MOV arresters came into being in 1982-83. Maybe RUS should reinforce use of MOV's on underground in the material list under Uae surge arrester—MOV only.

Response: RUS agrees and has removed all notes referring to parallel arresters as they are no longer applicable to this RUS construction standard.

(17) Do not specify elbows as part of transformer drawings to be consistent with UM3 and UM33 drawings. If RUS would like to specify, UG7 needs 2 elbows not 1.

Response: RUS agrees to specify two elbows on drawing UG7 to be consistent with other drawings.

(18) On UM3-14 delete UM3-15 and UM3-16. Only difference between -14 and -16 is the pad, which is spaced separately. -15 is obsolete. Change drawing to UM3. Redraw UM3-14 now as UM3 and show a 3-point junction to reflect the real world way the inside of the cabinet would look. What's illustrated doesn't exist.

Response: Drawings UM3-15 and UM3-16 are obsolete and have been removed. For the ground connections to the enclosures, the ground wires are hidden. RUS changed the mounting arrangement to reflect field application.

(19) In drawing UX4, since we show loops in ground rod connections for transformers and pad mount equipment, shouldn't there be 2 connections to the ground rod?

Response: Two connections in an enclosure are required to provide additional mechanical protection and to complete the ground loop. Connections to ground rods should be isolated and, mechanically, should not be disturbed. Therefore, dual connections to the ground rods are not needed.

(20) On UX11 drawing, the note about 3 ft. max. is not needed. This connection has lead length of effectively 0 feet. The note is misapplied.

Response: The note has been removed for the reasons presented in this comment.

(21) Section 18: There is no reference to concrete vaults and their associated covers.

Response: Due to the wide variation of concrete vaults available, RUS does not have specific requirements for concrete vaults.

(22) Units UB1, UB3, UB2-1, UC2-1: The jumper between the top of the terminator and the top of the arrester crosses over the top of the crossarm. This will undoubtedly kill lots of birds.

Response: Due to limitations of what and how we can show details on drawings, jumpers in drawings are for demonstration purpose and may not reflect actual field installation. Usually raptors choose the highest point to perch in search of prey and rest. On the structure referred to in this comment, most raptors can be expected to perch on the pole top rather than the lower crossarm. However, in locations where there is a possibility that raptors may use the lower crossarm, borrowers may utilize insulated jumper wires for the connection cited by the commentor.

(23) Drawings UG17 and UG17B: Shows only one ground rod. Note that UM 48-2 shows two (2) ground rods which will help get below 25 ohms.

Response: The ground rods on the drawings referred to by the commentor are not part of the cited drawings as is intended by their dotted appearance on these drawings. The ground rods are shown on these drawings only for reference perspective purposes. Grounding is required but for details on the grounding, borrowers would refer to the applicable RUS standard drawings on which grounding and ground rod use are included as part of the unit and included in the materials list. The applicable grounding drawings include notes that advise borrowers that depending on the condition and type of soil, installation of multiple ground rods may be necessary to attain a desirable ground resistance. These drawing notes also advise that, because use is site specific, numbers and type of ground rods are to be specified separately by the engineer.

(24) Drawings UM 3-44 and UM 3-45: Live bushing equipment in this type of enclosure is not a good safety practice. Suggest it not be allowed.

Response: The drawings were not shown as intended. As can be seen from the material listings for “be” and “el”, these items are to be supplied with bushing wells and thus the drawings need to be shown using elbows. The drawings were changed to agree with materials used.

(25) Drawing UM6 Page 5 of 8: In the Notes, items Uhf are referred to for resealing concentric neutral wires. What are they?

Response: Item U hf is a cable sealing kit. A note has been added to the drawing to better explain this item and its use. RUS accepted U hf products of various manufacturers are included in RUS Informational Publication 202-1, List of Materials Acceptable for Use on Systems of RUS Electrification Borrowers.

(26) Drawing UA1—UC6: RUS Bulletin 50-6 recommends, p connectors as required, where as, RUS Bulletin 50-3 required, p compression connectors. It would be desirable to maintain a consistent standard in the type of connector required in making the connection from the primary neutral to the pole ground.

Response: RUS requires compression connectors be used for grounding connections on underground construction. Many connector options may be use for overhead connections where conditions will generally be less adverse than underground construction. Compression connectors improve the chances for more permanent connections in underground construction.

(27) Drawing UM48-2: This drawing previously required #2 copper for the grounding wire. This requirement does not seem to be clearly spelled out in the current drawing.

Response: The minimum size of grounding wire to use is specified in the National Electrical Safety Code (NESC). As the size of grounding wire required will vary, RUS no longer includes wire size in the drawing and leaves determination and specification to the design engineer. RUS does not object to using wire sizes which exceed the minimum NESC requirements.

(28) Section 6.4 and 17.1: The two inches of sand is not recommended by the cable manufacturers. Sand serves as a thermal insulator and de-rates the cable ampacity. Also, for cable runs of a 1/4 mile or more, a potential galvanic action problem may be created for grounding the cable as required by NESC.

Response: Normally, good soil removed during digging of a trench is used as backfilling material. Sand is used as backfill in situations where removed soil is not suitable backfill material and consists of large rocks and/or sharp objects that could damage the buried cable. Sand may not be the ideal substitute as backfilling material. However, in most rural low load factor circuit use situations sand availability and economic feasibility make it a choice backfilling substitute.

(29) Drawing UK5: Locking mechanism should have provisions for company pad lock.

Response: NESC Rule 381G. requires enclosures to be either locked or otherwise secure against unauthorized entry. RUS requires and accepts enclosures that include the standard penta-head bolt, which provides the NESC intended security. Borrowers wishing to also use padlocking facilities in addition to having and using the required penta-head bolt may do so.

(30) Can a note be included on some drawings (such as UB1 where the neutral is so high) allowing the neutral to be lowered to get it down out of the primary?

Response: The neutral may be moved as long as the resulting installation meets proper clearances and does not violate safety codes.

(31) Several sections state that it is the responsibility of the borrower to ensure that the Contractor and the Owner. Is the borrower not the owner? Maybe this needs to be clarified.

Response: The commenter is correct in that the “Owner” and “Borrower” are generally the same entity. The “Owner” is the term used in RUS standard contracts to refer to the RUS borrower that executes the contract with the contractor. Borrower refers to a RUS borrower that has obtained financing assistance from RUS and has executed a loan contract with RUS. For accuracy purposes, specific bulletin sections deliberately refer to the contract terminology noted.

(32) Several sections state that it is the responsibility of the borrower to ensure. This needs to be changed to include the contractor as well.

Response: RUS does not have a regulatory relationship that allows establishment of requirements for contractors. Thus, RUS requires the borrower to ensure that the contractor complies with contract provisions. Borrowers are able to do so easily by use of RUS construction contracts which both the borrower and the contractor sign. RUS contracts make the design specification (RUS Bulletin 1728F-806 in this case) an integral part of the contract under which the contractor is contractually obligated to comply with the specification provisions.

(33) Section 17: Need to define what proper compaction is.

Response: Proper compaction provisions vary greatly and depend on local conditions. Compaction provision should be established by the borrower and completed in accordance with the borrower's satisfaction.

(34) Section 17.1: Is one inch too large for having in backfill?

Response: Backfill with pieces of less than one-inch (25 millimeter) size is recommended.

(35) Section 18.1: Gravel or sand is not needed under pads in all cases. This should be optional.

Response: RUS agrees and the term “shall” has been changed to “may.”

(36) Drawings UB2 and UC2: Why is the crossarm shown on a different side of the pole on these two drawings as compared with UB1 and UC1? Why are left side terminals and cutouts not out to end of arms to balance construction?

Response: Drawings UB1 and UC1 detail construction utilizing crossarm mounting arresters while drawings UB2 and UC2 detail construction utilizing bracket mounting arresters. Brackets mount on opposite sides of the pole to provide for accessibility and clearances. Equipment and hardware on the structures have been redrawn to depict balanced construction as suggested.

(37) Drawings UC5 and UC6: Intermediate arresters are shown (we guess that is why they are so large). Most cooperatives use riser pole arresters.

Response: We agree that the arrester size is confusing and revised the drawings to depict pole arrester use.

(38) Drawings UG6, UG7, UG17, UG17-2 and UG17-3: No slack is shown in primary cable. Most cooperatives loop the primary over from the secondary side to give slack so that cables can be parked or switched. Bulletin 50-6 showed the cable this way.

Response: We agree with the utility suggestion in this comment and revised the drawing by adding a note to allow slack in the primary cable installation.

(39) Drawing UG17: Requiring three phase switches as implied by note 6 should be optional.

Response: Note 6 on Drawing UG17 advises that three phase switching “should” be installed where ferroresonance may occur. The note is cautionary to help avoid equipment damage on three-phase installations where ferroresonance is a possibility. Because the word “should” is used and not “must”, three-phase switching would not need to be installed in situations where a borrower's engineer determined that ferroresonance would not occur.

(40) Drawing UJ1: A note is needed on the drawing stating that the connector blocks must be insulated to have a “dead-front” unit.

Response: These are drawings depicting various types of secondary connector blocks. It is not the intent of the bulletin to show dead front in this drawing. To help dispel possible confusion, the drawing includes a note that states “insulated covers are not shown”.

(41) Drawing UK6: If this handhole is metal, how is it to be grounded? Sign should be a warning not danger.

Response: RUS accepted metal pedestals must have grounding lugs available on the inside wall. A note has been added advising that all pedestals shall be grounded in accordance with the NESC. The placement of the safety sign has been relocated to the pedestal side (with the penta-head bolt lock) that opens. Both DANGER and WARNING signs have been added to the drawing's material listings. A WARNING sign should be placed on the outside of the enclosure where there is a potential hazard. A DANGER sign should be placed on the inside of the enclosure where there is an imminent hazard.

(42) Drawing UM1-6C: Having three or four different size pads might fit these size transformers better. Note #1 requires 4000# concrete, but most use 3000# which would be adequate for this.

Response: RUS agrees and has amended Note 1 of the drawing to specify the minimum at 3000 pounds per square inch (20 megapascals).

(43) Drawings UM3-44 and UM3-46: This is a dangerous installation since it is not dead front. A bushing insert can be installed in the recloser and then primary cable run to it to make everything deadfront.

Response: The drawings were not shown as intended. As can be seen from the material listings for “be” and “el”, these items are to be supplied with bushing wells and thus the drawings needs to be shown using elbows. The drawings were changed to agree with the materials used.

(44) Drawing UM6-27: Needs to be omitted.

Response: RUS agrees and has deleted this obsolete drawing.

(45) Drawing UM8-2: Ground rod connector has to be above grade as per code. Does the post need to be a minimum size, such as 4 x 4 inches?

Response: Section 250-52(c)(3) of the National Electrical Code requires that the upper end of a driven ground rod be flush with or below ground level unless the rod end and the grounding electrode conductor attachment are protected against physical damage. The RUS drawing shows the top of the rod well beneath grade to depict greater protection for the rod end and the grounding attachment.

RUS has included a note to require a minimum post size of 4 inches (10 centimeters) square or diameter.

(46) Drawing UM8-4: Why not show conduit coming in bottom of meter base to eliminate the elbow?

Response: RUS agrees and has revised the drawing to show cable entering from the base instead of from the side of the meter.

(47) Drawing UM8-6: Why cannot a meter be mounted to transformer? Utilities do this all the time.

Response: RUS does not believe such installations to be prudent. Mounting metering equipment onto the wall of padmounted transformers will require some cutting and drilling which will expose untreated transformer metal surfaces. These surfaces overtime will corrode prematurely and may cause serious problems.

In addition, vibrations from the transformer may affect the meter operation. Also, anytime a transformer is changed out, the meter has to be changed as well.

(48) Drawing UM12: Should this sign meet ANSI Z535 standards also? Would it be a Notice or a Warning or a Caution?

Response: RUS agrees there may be confusion with this drawing and revised the drawing by adding the signal word “WARNING” to the label. A note was also added requiring the sign to comply with ANSI Z535.

(49) Drawing UM26: Needs to be omitted. Nobody uses these anymore.

Response: RUS agrees that this drawing depicts outdated construction and removed the drawing.

(50) Drawing UM48-3: Is anode needed for jacketed cable?

Response: The sacrificial anode (Item U si) shown as a hidden line is optional. Some RUS borrowers prefer to install anodes at all ground points because gophers might chew through the jacket and expose the copper neutrals. The sacrificial anode will provide corrosion protection to such exposed neutral wires preventing a loss of neutral integrity.

(51) Drawing UX5: Need to show a minimum distance between ground rods as are done on other drawings.

Response: RUS agrees and has revised the drawing to show a minimum spacing of 6 ft. (1.8 m) between multiple ground rods. (As a general rule, RUS recommends that separation of ground rods be no closer than the length of the ground rods used. When rods are closer to one another than their length they will magnetically influence one another and degrade grounding effectiveness.) A note was also added to advise that multiple rods may not fit inside the enclosure. Where spacing inside an enclosure does not allow the 6 ft. (1.8 m) separation between multiple ground rods, one rod is to be installed inside the enclosure and the other outside. The ground loop has been redrawn to show a complete loop with a conductor feed from the loop down to the ground rod.

(52) Drawing UM7-1: There is no minimum ground clearance shown on any pole structures. If RUS does not want to show minimum clearances, perhaps a note regarding the source for clearance information would be in order.

Response: RUS agrees there is possible confusion here. Clearances were omitted purposefully because alternative working methods may be implemented along with appropriate alternative working clearances as a means of providing safety. To allay concerns of this comment, RUS revised the drawing by adding a note which states that clearances must meet NESC requirements.

(53) Certain existing drawings (UC5) are a different design from the proposed drawings. Certain materials used are different and the specification will also have different record units.

Response: RUS agrees and has changed the drawing numbers to the applicable drawings.

(54) When RUS changes a construction specification, maybe RUS should add a suffix to indicate that change (example: UC5 change to UC5A or UC5-1, or UC5-98)

Response: RUS agrees and has changed the drawing numbers to the applicable drawings.

(55) Drawing UM48-2: The drawing shows the use of two ground rods in the elevation view, however, the quantity of rods is left open in the material list. I and a number of fellow workers and clients feel that it would be helpful to add a note 3 stating that the quantity of rods is to be determined by the specifier and that the use of two rods rather than one at a multi-phase transformer or enclosure is not a standard or a requirement by RUS.

Response: RUS agrees. Depending on the condition and type of soil, installation of multiple ground rods may be necessary to attain a desirable ground resistance. Thus, ground rods need to be specified separately.

In response to this comment, RUS added the following note to the drawing: “The quantity of rods is to be determined by the specifier. The use of two rods rather than one at a multi-phase transformer or enclosure is not a standard or a requirement by RUS.”

List of Subjects in 7 CFR Part 1728

• Electric power
• Incorporation by reference
• Loan programs-energy
• Rural areas

For reasons set out in the preamble, RUS is amending 7 CFR part 1728 as follows:

PART 1728—ELECTRIC STANDARDS AND SPECIFICATIONS FOR MATERIALS AND CONSTRUCTION

1. The authority citation for part 1728 continues to read as follows:

Authority: 7 U.S.C. 901 et seq., 1921 et seq., 6941 et seq.

2. Section 1728.97 is amended by revising paragraph (a) and by adding, in numerical order, the entry for Bulletin 1728F-806 to paragraph (b). The revision and addition read as follows: