sand seeps through retaining wall
I have a wooden retaining wall, about 3 feet high, along a driveway. The sand from the soil behind it gradually seeps through and ends up on the driveway. Every half a year or so I have to remove a pile of sand from under the wall, while the soil behind the wall settles down. Is there a way to repair this? The wall itself is in good shape, I would not want to replace it.