As requested, identification, a complete description as well as a standard and modified Proctor Test for the supplied material, mostly sand has been completed.  The sample material was tested for a proposed subgrade using the Standard Proctor Test at a 98% compaction rate for a landfill site.  The Ministry of the Environment supplied the material.

A complete description of the material identified can be found appended to the memo on the material identification work sheet to follow.  An analysis was made for the sample and it was based on the Standard Proctor Test at a 98% compaction.  The Standard Proctor Test indicates the soil density or the degree of compaction that must be achieved in order for the fill to be considered satisfactory.  The requirements are based on the results of laboratory compaction tests.   Such tests determine the maximum density a soil can be compacted without crushing the soil particles.  The maximum density occurs at a certain moisture content called the optimal moisture content.  The most widely used procedure for moisture and density testing consists of compacting the soil in layers in a cylindrical mold by use of a drop hammer which will deliver a compacting force on the material.  In order to establish a moisture and density relationship for a soil, separate samples are each compacted at different water contents.  The compacted dry density and water content is then determined.  A complete detailed procedure for performing the standard proctor test is presented in the American Society for Testing Methods (ASTM) under the D-698 designation.  The modified Proctor test is also outlined in the D-1557 designation.
A 98% compaction was used for the standard proctor test for the subgrade. Results of this testing procedure, as well as a detailed graph displaying the optimum moisture content, can be found on the appended compaction test worksheets.  (These tests met or exceeded the 98% compaction specified.) If the moisture content range is more than 10%,  it is too saturated, and therefore would not be suitable for compaction.  The actual range of moisture content is between 6% - 10%.  Between the values of 6% AND 9% moisture content, maximum density should be at its peak.  From the graph shown on the appended sheet, the maximum dry density is about 2.2 tonnes/m3  and the optimum water moisture content is about 8.0%.  At each test a drop hammer was used to establish a uniform density that has been achieved for each lift of compaction fill.

The soil compaction provides the foundation support for many different types of structures such as a landfill site.  Properly placed and compacted the resulting soil mass has strength and support capabilities good and often better than many saturated soil formations.

The material, mostly sand, was identified and a standard and modified proctor test analysis was completed.  It was found to be a suitable material for the proposed  subgrade as a liner in a landfill site.
If further testing or information is required, please contact me.

Yours truly,
 

Karla McDonald