I'm building a retaining wall from concrete blocks. The foundation will be 8 inches of 3/4 inch gravel compacted with a plate compactor. The trench is dug, but it has rained a good bit the last two weeks, and while not soggy things are wet. (There are no puddles in the trench, all the rain has been absorbed into the ground. I can walk in the trench and hardly leave footprints.) How much should I allow the ground to dry out before adding my gravel and compacting? Is it bad to compact onto ground that is wet but not soggy?