A bill approved by the New Jersey Senate Environment Committee would reimburse the owners and operators of every child care center in the state for the cost of site assessments. The move comes in response to the Kiddie Kollege day-care center that was opened unwittingly on the site of a former thermometer factory, where children were potentially exposed to mercury contamination. The state Department of Environmental Protection estimates that the payments for site assessments will amount to between $6 million and $7 million. The bill will now be taken up by the Senate Budget and Appropriations Committee.