sitemap Jumpmenus and SEO

is too many links on a page good or bad for seo?

[spliffy]

On a site that i am working on a scientific site that has a pretty deep tree structure about 8 - 10 directories deep across 6 sections so it's a good 50+ links. I was thinking about using a jump menu. ALA style, based on simple unordered lists. ie.
standards compliant, minimal js.

<code>
<ul>
<li>topic 1
<ul>
<li>topic1a</li>
<ul>
</li>
<li>topic 2</li>
</ul>
</code>

i am also planning on using a breadcrumb trail, and submenu with subdirectory listings and the content will have links to the next subdirectory content as well as it is referred to through out the current topic level.
So with this formula at the most a single link could come up 4 times on the same page with the max 60 - 70 navigation links.

one thing is that the mondo jump menu would be written below the content of each page in the mark up and absolutely positioned in divs to be above.

so my question is, is this a really good thing for SEO? or a really bad thing? will this just look like some link farm? even if my code is perfectly semantic with good (but far less) content?