A New York federal judge on Friday scuttled a proposed settlement of lawsuits filed by more than 10,000 Ground Zero workers seeking compensation for health problems triggered by their exposure to ash and dust spewed into the air after the 9/11 terror attacks. Judge Alvin K. Hellerstein, who has presided over the often bitter litigation for eight years, ordered the parties to renegotiate a deal, complaining that it provided too much money for attorneys and insufficient information for plaintiffs.