Page 710 - skylineranchfeiraddendum1216

Qal #1
(from terminus of Alluvium-clean sand 85
Canyon Crest Drive)
Qal #2
(from terminus of Alluvium-sand 64
Canyon Crest Drive)
Tmc #1
(from terminus of Mint Canyon Fm. – Silty 30
Sandstone
Canyon Crest Drive)

Durability, Specific Gravity, and Absorption Testing

Samples of the oversize rock present within the alluvium, Saugus Formation, and

Mint Canyon Formation were collected and crushed into 1” diameter or less fragments

for determination of their quality for various on-site construction material uses. The

majority of these oversize rocks consisted of subrounded cobbles and boulders of granite,

granodiorite, syenite, gabbro, and gneiss. The crushed material was submitted to BTC

Laboratories for testing, the result of which is presented in the following table.

Sample Durability Percentage Wear Apparent Absorption
Index ASTM C 131 Specific California Test
California Test 100 Rev. 500 Rev. Gravity Method No. 206
Method No. 229 ASTM C127
Alluvium Oversize
Rock 65 9.5 37 2.67 0.6%
Saugus Fm. 70 14.1 50.5 2.65 1.1%
Oversize Rock
Mint Cyn Fm.
Oversize Rock 75 11.9 44.7 2.64 0.9%
2006 Greenbook 45
Criteria for Rip Rap 52 Minimum -- Maximum 2.5 Minimum 4.20 Maximum
2006 Greenbook
52
15
Criteria for Crushed -- Maximum Maximum -- --
Aggregate Base

Based on these test results, the oversize rock from the alluvium and Mint Canyon

Formation would pass the 2006 Standard Specification for Public Works Construction

(Greenbook) criteria for Durability, Percentage Wear, Apparent Specific Gravity, and

Absorption for use as rip rap. The durability results indicate that the rock from all three

A-557