Quail Hollow Utility Trench Sand

This technical note and the following data were developed from tests conducted by Graniterock’s Research Technical Services group, Soil Control Lab and Kleinfelder, Inc.

Major utility companies have written specifications concerning trench fill sand applications. These specifications establish acceptable limits concerning gradations, organic impurities, sand equivalents, pH, chloride content, sulfate content, and compaction.

These utilities rely on several suppliers, including Graniterock, to provide sand meeting their specifications. Below you will find the typical utility requirements as well as Graniterock’s Utility Trench Sand results.

Sand color is a significant issue. The trench fill material must be lighter than normal soil color so that a sudden color change will alert contractors they are working in a utility trench. The goal is to avoid damage to buried utilities.

The correct pH and low level chloride and sulfate concentrations are extremely important to maintain the integrity of critical transmission components. The goal is to minimize corrosive attack on the utility’s equipment to extend service life. Extended service life will reduce operating costs, reduce service interruptions and reduce the possibility of potential leaks.

Utilities are very selective about their sand sources. Before Graniterock was designated as an acceptable trench fill sand supplier, we were required to submit our technical information for review. After a successful review, the utility then dispatched its own laboratory technicians to our Quail Hollow facility for a site visit. They explored our deposit and took samples for analysis in their laboratory. Only after the utility verified our test data through its own testing were we approved as an acceptable source.

For more information, please contact Mike Munn at 408.487.3112 or mmunn@graniterock.com.


Percent Passing (Maximum Dry Density is 108. 0 pcf with an optimum water content of 4.0%)

Additional Criteria Typical Utility Specification Quail Hollow Utility Trench Sand
Organic Impurities No Darker Than Plate 3 Lighter Than Plate 3
Sand Equivalent ≥ 20 70
PH ≥ 4.5, but <9 7.8
Chloride Content ≤ 500 ppm 2.2
Sulfate Content ≤ 150 ppm 9.6
Compaction 95% 95%

Percent Passing:

Sieve Typical Utility Specification Quail Hollow Utility Trench Sand
½″ 100 100
#4 75-100 99
#8 70-100 99
#16 65-100 93
#30 60-100 61
#50 40-70 42
#100 0-30 13
#200 0-15 6.5