Hey Paul,
here is the explanation:
www.simodal.com and www.simodal.com/index.htm are considered separate pages by google, although both are your sites "starting point". Some Content Management Systems (CMS) make thiis mistake, i.e. delivering the same page and not distinguishing between simodal.com/ and simodal.com/index.htm.
As said before, you should decide whether all your pages should be www.simodal oder just simodal.com. There is a great Whiteboard-Friday Video by Rand on this toppic. Then you should rewrite your URLs to either version.
Additionally you might want to add a rel canonical to your page, maybe just to your starting page. a
<link rel="canonical" href="http://www.simodal.com/" />
on your starting page would tell google to ignore the /index.htm and use /
But watch out, rel canonical is somewhat tricky...but there are good tutorials here.
To be honest: I know quiet a lot of pages, that make this mistake. Google should be able to correct this, so dont qorry about rankings. You should however do the redirect www. (or the opposite) as this will trigger googles DC filter. Also: if you plan to use SSL (https:// ) make sure that these pages are also not indexed, best by using rel canonical.