That doesn't seem correct. No matter how good your content was I don't think it would happen very often or even at all. Having a bounce rate of under 5% and then having an average time on site rate of under 1 min does seem like it would happen. Maybe 1 in every million sites. The only way I think this may be possible, but not 100% sure is that if your traffic is from Stumbleupon as I noticed I get 2 hits per visitor even if they are just on the one page, making it not increase the bounce rate, there could also be some other sources of traffic that may do this as well. I went to your site and caused another bounce rate increase as I just went on the one page to look at it. I must say that you have done a great job with it as it does look very good and attractive. Truthfully it's very hard to get a bounce rate of under 10% if you advertise your site all over the web, the reasons for this is because many people will click on your link to find the information that they are looking for, but once they hit your site they may then find that your sites content was not what they were quite looking for and will then go to the next site straight away.
Bounce rate (sometimes confused with exit rate) is a term used in web site traffic analysis. It essentially represents the percentage of initial visitors to a site who "bounce" away to a different site, rather than continue on to other pages within the same site. The formula used to calculate bounce rate is: Bounce Rate = Total Number of Visits Viewing One Page / Total Number of Visits Good a bounce rate under 20%, anything over 35% is cause for concern, 50% (above) is worrying.
low bounce rate is always good. low the bounce rate means for more is the time visitor stays on the page.