This extreme difference in unit weight compared to other materials makes EPS
geofoam an attractive fill material. Because it is a soil
alternative, EPS geofoam embankments can be covered
to look like normal sloped embankments or
finished to look like a wall (Humphrey and Maion
1992; Eldin and Senouci 1992; Humphrey and Sandford
1993; Frascoia and Cauley 1995; Humphrey and
Sandford 1993; Humphrey et al. 1998). Using modified
expanded polystyrene (MEPE) with sand as
retaining wall backfill or subbase has several potential
benefits.