Major developments in the aftermath of Hurricane Katrina: —Tests show the putrid air rising from New Orleans' slowly receding floodwaters is not overly polluted. Mayor C. Ray Nagin says the clean bill of health for the city's atmosphere would allow the tourist- friendly French Quarter and central business district to reopen as early as Monday. The floodwaters still contained dangerous levels of sewage-related bacteria.
—In Washington, Senate Republicans scuttle an attempt to establish an independent, bipartisan panel patterned after the 9/11 Commission to investigate what went wrong with the response to the hurricane. Separately, a Senate committee opens a hearing on the disaster, with the panel's Republican chairwoman saying that changes instituted after Sept. 11 in the government's emergency preparedness failed their first major test during Katrina.
—Authorities say at least two of the Katrina refugees scattered around the country have committed suicide, and 55 others have died as well, most of them sick and elderly people whose conditions may have been worsened by their stress.
—The Army Corps of Engineers expects to award $1.5 billion in government contracts by the week's end to fully clear debris from the city.
—Lights flicker on in many New Orleans neighborhoods. About 168,000 customers were still without power, mostly in places still flooded, but that number had gone down 10,000 in a day.
—Full mail service resumed in more than 80 percent of the post offices affected by the hurricane.
