After applying Perma-Zyme, you can test your soil to ensure that it cured properly, using either a nuclear density gauge or the coring method.
Nuclear Density Gauge
A nuclear density gauge is a device that measures the soil's density on-site by inserting a rod into the soil. This test is often very effective and easy, and oftentimes geotechnical laboratories will perform this test for you.
If significant time has elapsed since the Perma-Zyme treatment, the soil is often too hard to perform this test.
Coring
With this method, a coring drill obtains a core sample of the cured soil. A geotechnical laboratory core can then test the soil for compressive strength in a lab setting.