Group 1 - The investigation around the environment of the Brownstone Peixin Kindergarten found no lead pollution in the surrounding area, with all tested samples meeting relevant environmental quality standards [1][2] - Air samples showed lead concentrations ranging from 0.006 μg/m3 to 0.026 μg/m3, significantly below the limits set by the National Ambient Air Quality Standards [2] - Groundwater samples did not detect any lead, and soil samples contained lead levels of 24.6 mg/kg and 27.6 mg/kg, both below the risk control standards for construction land [2] Group 2 - Surface water from the water source showed a lead concentration of 0.92 μg/L, which meets the Class I (excellent) standard of the Surface Water Environmental Quality Standards [2] - Historical satellite imagery indicated that the site of the kindergarten was previously an agricultural vineyard with no lead-related activities prior to its development in 2017 [2]