Chapter 4 of 821% of exam

Subsurface, Surface, and Elevated Piping Work

This is the largest section of the exam at about 21%: shoring and sloping, erosion control, tunneling and boring, installing pipelines, connecting and testing systems, and connecting dry utilities. Cal/OSHA's excavation rules and California's 811 law supply many of the numbers. The PrepPass CSLB General Engineering (A) Study Guide covers this section in depth, with worked examples, named traps and a chapter quiz.

Excavation protection

Cave-in protection is required at 5 feet and deeper (unless in stable rock), chosen by a competent person from soil classification.

Maximum slopes
Type A 3/4:1, Type B 1:1, Type C 1-1/2:1 for excavations under 20 feet.
Cal. Code Regs. tit. 8, 1541.1 App. B
Egress
Ladders or ramps in trenches 4 feet or deeper, within 25 feet of lateral travel.
Cal. Code Regs. tit. 8, 1541
Spoil
At least 2 feet back from the edge.
Cal. Code Regs. tit. 8, 1541

Pipelines

Pipe is laid to line and grade on uniform bedding, restrained at bends, tested before burial, and kept away from sewers.

Tolerance zone
24 inches each side of the marks; expose facilities by hand or approved vacuum before machines dig there.
Gov. Code 4216, 4216.4
Water main separation
10 feet horizontally and 1 foot above parallel sewers; 4 feet from storm drains.
Cal. Code Regs. tit. 22, 64572
Pressure test
Caltrans Method A: 125 psi for 1 hour with no more than 5 psi drop.
Caltrans Standard Specifications 2025, 20-2.01A(4)(b)

Erosion and tunneling

Sites of an acre or more need stormwater permit coverage; bores of 30 inches or more are tunnel work.

Stormwater
Construction disturbing one acre or more needs Construction General Permit coverage.
State Water Board, Order 2022-0057-DWQ
Tunnel Safety Orders
Apply to boring and pipe jacking 30 inches or larger and shafts over 20 feet.
Cal. Code Regs. tit. 8, 8403

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