July 21 (Bloomberg) -- Cleanup work is accelerating this weekend to restore traffic and commerce in midtown Manhattan, where a steam pipe blast left one person dead and 45 injured.

Lighter traffic in the mostly commercial district will ease access by crews, Christopher Olert, a spokesman for utility owner Consolidated Edison Inc., said in an interview yesterday. New York City aims to reopen 42nd Street, a major crosstown thoroughfare and bus route, for the start of the workweek, Deputy Mayor Edward Skyler told reporters.

Con Edison must stabilize live electrical cables and remove a tow truck that plunged into the 25-foot (7.6-meter) crater caused by the explosion at 41st Street and Lexington Avenue, said Bill Longhi, senior vice president for operations. The utility will then begin assessing how to restore the site, he said at a press conference.

``We essentially have to rebuild our electric system and steam system within that entire intersection,'' Longhi said. ``That's going to be a pretty massive effort.''

The explosion occurred during the evening rush hour on July 18 a block from Grand Central Terminal, sending plumes of steam and debris into the air. Traffic in midtown Manhattan was snarled during the next day's rush hour, subway service was interrupted and thousands of Manhattan office workers were kept from their jobs.

Crews were hosing down buildings today to remove mud and debris from the explosion and collecting the water for disposal, said Martha Liipfert, a spokeswoman for Con Ed. The tow truck will be removed from the site later today.

Cause Remains Unknown

While subways were operating normally by the end of the work week, streets surrounding the blast site remained closed in a ``frozen zone'' that city officials said would shrink as cleanup progresses.

The cause of the explosion remains unknown, Longhi said. Utility workers repaired routine steam leaks near the site in recent weeks and had inspected the intersection for signs of steam problems about six hours before the blast, he said.

The city expects to complete safety inspections along 42nd Street so that small businesses may begin reopening July 23, Skyler said. Officials also aim to reopen Lexington Avenue to pedestrians, he said. Third and Vanderbilt avenues have reopened.

About 125 storefront shops were closed by the blast, and city officials will go door-to-door offering interest-free loans as large as $10,000, said Robert Walsh, commissioner of the city's Department of Small Business Services. Businesses also can file claims with Con Edison.

The Department of Small Business Services said it had no estimate of losses suffered by companies in the frozen zone, which police have blocked off to everyone but utility workers, police and emergency management officials.

Cost to Businesses

Kathryn Wylde, president of the New York City Partnership, an organization of corporate chief executives that promotes commerce in the city, estimated that at least $30 million had been lost, mostly to the retailers in the area.

``If it goes into Monday and Tuesday, these numbers will ratchet up into hundreds of millions,'' she said. ``The frozen zone surrounds the transportation hub of the nation's busiest central business district so it has to be expensive when you shut it down.''

Steam service, used by large buildings for hot water and sometimes cooling, may be restored to all buildings in the next couple of days, Longhi said. Of 18 buildings initially shut from steam service, 13 have been restored, he said.

Air sampling has found no trace of cancer-causing asbestos, once used as insulation on steam lines, Skyler said. Mayor Michael Bloomberg said officials took 76 samples of debris and found 20 with asbestos. Eighteen of these were trace amounts and two were whole pieces of the mineral that had been used as insulation wrapping the pipes.

The mayor is founder and majority owner of Bloomberg News parent Bloomberg LP.

To contact the reporters on this story: Jim Polson in New York at jpolson@bloomberg.net; Henry Goldman in New York at hgoldman@bloomberg.net

Last Updated: July 21, 2007 11:37 EDT