An investigation into the cause and extent of chemical contamination in Vermont compost has been hampered by conflicting test results. The results have frustrated state and local officials, who had hoped to have more answers by now about what's caused some commercial compost to damage garden plants.

Gardeners who saw their crops destroyed by contaminated compost may be eligible for a refund and compensation.

Newscast: Saturday, July 7, 2012, 8:35 a.m.

The Vermont Agency of Agriculture is trying to determine the source of trace levels of two herbicides found in some compost used by gardeners that has damaged some vegetable plants but is not suspected to be a threat to human health.