Joint Trench Installation
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SPECIFICATIONS FOR APPLICANT PROVIDED TRENCH
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- Trenches are to be excavated according to The Gas Company
- Trenches shall be sized to provide a minimum vertical clearance of twelve inches above power conductors of any size or type, and a minimum separation of six inches from all other substructures, vertically or horizontally.
- All gas Main and Service piping shall have a minimum of thirty inches cover below finished grade and flow line. Permit issuing agency may require additional cover to comply with local or state regulations. All trenches must be level and free of debris at the time gas lines are to be installed.
- All joint Trench and "Gas Only" trench will be backfilled with sand to maintain a minimum of twelve inches of cover over all gas main and service pipe in normal soil and a minimum of eighteen inches in rocky soil, included in joint trench reimbursement. (Actual depth to be determined by The Gas Company representative).
- Joint Trench or "Gas Only" trench shall have a minimum six inch sand pad in rocky soil conditions, included in joint Trench reimbursement. (Actual depth to be determined by The Gas Company representative).
- The Developer is responsible for supplying rock-free sand or Gas Company approved native soil (see Note below) to the job site prior to installation -of gas main.
- Trenches shall have a minimum of two foot spoil setback from side of excavation. Any excavation five or more feet shall be shored to The Gas Company specifications by trench subcontractor.
- Refrain from pouring cross gutters and curb returns until it is verified there will be no conflict with gas main installation.
- All offset trenches are to be at 90° angles. All service-to-main connections are at 90° angles. All main-to-main connections are to be installed at 90° angles. No roping of gas piping is allowed.
- If Developer chooses to install base lift paving prior to installation of gas main, natural gas casings will be installed per The Gas Company specifications; i.e. size, location, etc. by developer.
- Casing installation is approved for street crossings only.
- Developer is responsible for marking the riser location and finish grade if house lines are not installed at time of gas installation.
- Gas meter locations must be a minimum of three feet from any source of ignition.
- Branch service tie-ins should be excavated between right-of-way and garage foundations.
- Developer is responsible for installation of all other dry & wet utilities prior to gas installation.
- Once installed, Developer will be responsible for cost of repair or relocation costs of any gas facility which has been tampered with inside the project limits.
- Developer's subcontractors are to notify Underground Service Alert of Southern California, A.K.A. Dig Alert at 1-800-227-2600 prior to excavating and are required to hand dig over any Gas Company facility.
NOTE
Backfill material used for bedding and shading of the gas pipe shall consist of natural sand, manufactured sand, or a combination of both and shall conform to the physical properties listed below.
Property |
Test Method |
Specification Requirements |
Organic Impurities |
ASTM C-40 |
Supernatant shall not be darker than Plate 3 when compared to standard Gardiner Color Series |
Sand Equivalent |
ASTM D-2419 |
20 minimum |
Compaction Characteristics |
ASTM D-1557 |
When material is compacted to a relative compaction of 95% or greater as determined by ASTM D-1557, the material shall not slough when cross trenched. |
Graduation |
ASTM C-136 & ASTM C-117 |
Sieve Size |
Percent Passing (By Weight) |
|
3/8"< |
(9.5MM) |
100 |
|
No. |
4 (4.75MM) |
95-100 |
|
No. |
8 (2.36MM) |
90-100 |
|
No. |
16 (1.18MM) |
80-100 |
|
No. |
30 (600MM) |
65-100 |
|
No. |
50 (300MM) |
40-70 |
|
No. |
100 (150MM) |
0-30 |