Signup for Hanford sitewide tours starts today at 6 p.m. on the internet.

Seats could go quickly since fewer tours are being offered this year.

Seats also remain available for tours of Hanford's historic B Reactor, after signup for those tours started at noon Saturday. However, the weekend tour seats available by phone and the internet have all been taken for 2013.

The Hanford sitewide bus tours include a briefer look inside B Reactor plus a tour of environmental cleanup work across the nuclear reservation. Tours are available from April 9 to Sept. 12.

Participants must be U.S. citizens and at least 18 years old for the sitewide tours. For B Reactor tours, available April 1 to Sept. 21, there is no citizenship requirement and participants must be at least 12 years old.

To sign up for a sitewide tour, go to www.hanford.gov and click on "Hanford Tours" under "Quick Links" on the right-hand side of the page. Information to sign up for B Reactor tours is available there also. No telephone signup for sitewide tours is available, but B Reactor tour reservations are available by calling 509-376-1647.Y