After WAVING your webpage the following errors are related to Section 508f
ERROR: Image map missing alternative text
Alternative text is not present for an image that has hotspots.
Ensure the alternative text for the main image map
image is appropriate. The alternative text is typically empty (alt=""),
unless the image conveys content not conveyed in the hotspots. Ensure
that the linearized reading/navigation order and alternative text of
each hot spot is correct.
ERROR: Image map area missing alternative text
Alternative text is not present for an image map area (hotspot).
Supply alternative text that describes the function of the image map area (hotspot). Ensure that the linearized reading and navigation order of each hot spot is correct.