Same formula using drop spreader - 2-4 oz per 10 sq ft. I do the math and figure out the correct spreader setting if applying to entire basin. If one is spot treating I disregard the formula and apply heavy since I'm focused on a much smaller area and using significantly less. I don't want to take a chance on gravel/sand veins so I really nuke it then plate with high plasticity clay in 6" lifts. The localized treatment has been very effective for me so far, but the trick is having a dry basin and access to the problem areas - 99% of issues are realized following construction and deal with full ponds which inhibit our ability to identify suspect material areas and localize the treatment.

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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