SECTION 02781

SITE GROUNDING SYSTEMS

PART	GENERAL

SECTION INCLUDES

Electrodes.

Connectors.

Conductors.

RELATED SECTIONS

Section 02225 - Trenching.

Section 03300 - Cast-in-Place Concrete.

Section 16170 - Grounding and Bonding.

Section 16670 - Lightning Protection.

UNIT PRICE - MEASUREMENT AND PAYMENT

Rod Electrode:

Basis of Measurement: Per unit.

Basis of Payment: Includes purchase, delivery, and installation of rod electrode.

Active Electrode:

Basis of Measurement: Per unit.

Basis of Payment: Includes purchase, delivery, and installation of rod electrode.

Mechanical Connectors:

Basis of Measurement: Per unit.

Basis of Payment: Includes purchase, delivery, and installation of connector.

Exothermic Connectors:

Basis of Measurement: Per unit.

Basis of Payment: Includes purchase, delivery, and installation of weld.

Conductors:

Basis of Measurement: Per linear [foot] [meter].

Basis of Payment: Includes purchase, delivery and installation of wire.

REFERENCES

ANSI/IEEE C2 - National Electrical Safety Code.

ANSI/NFPA 70 - National Electrical Code.

IEEE 80 - Guide for Safety in AC Substation Grounding.

IEEE 142 - Grounding of Industrial and Commercial Power Systems.

SYSTEM DESCRIPTION

Multiple [vertical] [plate] [rod] electrodes buried [in [straight line] [[circular] [square] [rectangular] pattern]] [around perimeter of [building foundation] [________]] [in configuration as indicated] [at intersections of horizontal electrode grid] [________].

Multiple horizontal electrodes buried [in [straight line] [ring] [grid] pattern] [around perimeter of [building foundation] [________].

Single [vertical] [horizontal] [plate] [rod] electrode for local grounding at [utility transformer] [________].

DESIGN REQUIREMENTS

Conform to IEEE 142.

Substation Grounding: Conform to IEEE 80.

PERFORMANCE REQUIREMENTS

Overall Resistance to Ground: [5] [25] [____] ohms.

SUBMITTALS

Submit under provisions of Section [01300.] [________.]

Shop Drawings: Indicate layout of grounding system and installation details.

Product Data: Provide for grounding electrodes and connectors.

Test Reports: Indicate overall resistance to ground [at each system].

Manufacturer's Instructions: Include instructions for storage, handling, protection, examination, preparation and installation of exothermic connectors.

PROJECT RECORD DOCUMENTS

Submit under provisions of Section [01700.] [________.]

Accurately record actual locations of electrodes and connections.

QUALIFICATIONS

Manufacturer: Company specializing in manufacturing Products specified in this Section with minimum [three] [________] years [documented] experience.

REGULATORY REQUIREMENTS

Conform to requirements of [ANSI/NFPA 70] [ANSI/IEEE C2].

Furnish products listed and classified by [Underwriters Laboratories, Inc.] [testing firm acceptable to authority having jurisdiction] as suitable for purpose specified and shown.

FIELD SAMPLES

Provide under provisions of Section [01400.] [________.]

Provide sample installation of [[vertical] [horizontal] electrode] [, grounding well] [, active electrodes] [and] [exothermic connector].

COORDINATION

Coordinate work under provisions of Section [01039.] [________.]

Coordinate work with site excavating, backfilling and final grading.

PART	PRODUCTS

ROD ELECTRODES

Manufacturers:

[________________________________] Model [_________].

[________________________________] Model [_________].

[________________________________] Model [_________].

Substitutions: Under provisions of Section [01600.] [________.]

Material: [Copper] [Copper-clad steel].

Diameter: [1/2] [3/4] [____] inch ([13] [19] [____] mm).

Length: [5] [8] [10] [____] feet ([1.5] [2.4] [3] [____] m).

ACTIVE ELECTRODES

Manufacturers:

[________________________________] Model [_________].

[________________________________] Model [_________].

[________________________________] Model [_________].

Substitutions: Under provisions of Section [01600.] [________.]

Description: Metallic salt filled copper tube electrode.

Shape: [Straight.] [L-shaped.] [As indicated.]

Length: [8] [10] [12] [20] [____] feet ([2.5] [3] [4] [6] [____] m).

Connector: Provide [U-bolt pressure plate.] [connector for exothermic welded connection.]

MECHANICAL CONNECTORS

Manufacturers:

[________________________________] Model [_________].

[________________________________] Model [_________].

[________________________________] Model [_________].

Substitutions: Under provisions of Section [01600.] [________.]

Material: Bronze.

EXOTHERMIC CONNECTIONS

Manufacturers:

[________________________________] Model [_________].

[________________________________] Model [_________].

[________________________________] Model [_________].

Substitutions: Under provisions of Section [01600.] [________.]

WIRE

Material: Stranded copper.

Horizontal Electrodes: [4/0] [2/0] [2] [____] AWG, minimum size.

Connections to Electrodes: [2/0] [2] [____] AWG, minimum size.

Bonding Other Objects: [2/0] [2] [____] AWG, minimum size.

GROUNDING WELL COMPONENTS

Well Pipe: 8 inch (200 mm) diameter by 24 inch (600 mm) long [clay tile] [concrete] pipe with belled end.

Well Cover: Cast iron with legend "GROUND" embossed on cover.

Treatment Well Liner: 8 inch (200 mm) diameter [clay tile] [concrete] perforated pipe.

PART	EXECUTION

EXAMINATION

Verify completion of site backfill under provisions of Section [01039.] [________.]

Verify that final backfill and compaction has been completed before driving rod electrodes.

Verify that trenching is completed before installing horizontal electrodes.

INSTALLATION

Install Products in accordance with manufacturer's instructions.

Install rod electrodes in vertical position with bottom at least [5] [____] feet ([1.6] [____] m) below frost line.

Install rod electrodes [________].

Install interconnecting wire [[2] [____] feet ([0.6] [____] m) below finished grade level] [below frost line].

Provide grounding wells [as indicated] [at each electrode] [at [________] electrode].

Provide cast-in-place concrete well under provisions of Section 03300. Construct as indicated.

CHEMICAL TREATMENT

Provide chemical treatment [where indicated] [at each vertical electrode site.] [________.]

Use magnesium sulfate (epsom salts) [, copper sulfate (blue vitriol)] [, calcium chloride] [or] [________].

****** [OR] ******

Use suitable ion-producing treating chemicals that are non-corrosive and non-toxic.

Trenching: Dig circular trench centered on electrode. Make trench 12 inches (0.3 m) deep with 18 inch (0.5 m) inside diameter. Uniformly distribute 50 pounds of treatment material in bottom of trench and cover with topsoil.

****** [OR] ******

Direct Treatment at Grounding Well: Fill 12 inches of treatment material in bottom of 24-inch deep well.

****** [OR] ******

Treatment Wells:

Location: Provide four uniformly spaced wells along 4 foot radius from vertical electrode.

Lining: Provide to depth of [5] [____] feet ([2.7] [____] m).

Well Pipe and Cover: Provide flush with finished grade.

Treatment: Fill each well to 12 inches (30 mm) below grade with treatment material.

Saturate treatment chemicals with water following application.

INTERFACE WITH OTHER PRODUCTS

Interface with lightning protection system installed under Section 16670.

Interface with grounding and bonding provided under Section 16170.

FIELD QUALITY CONTROL

Make final grounding system measurements three or four days after chemical treatment.

Test Procedures: IEEE 142, fall of potential method.

DEMONSTRATION

Provide systems demonstration under provisions of Section [01650.] [________.]

Demonstrate location of each accessible grounding connection and each chemical treatment well.

END OF SECTION