The samples were stored in polyethylene bags and shipped to previously assigned laboratories for further analysis. All concentrations and activities are expressed on a dry weight basis. 3.2. Laboratory analysis 210Pb analyses were carried out at Servicio Académico de Fechado (ICML-UNAM, Mexico), ...
Aggregate filled bags are easier to remove than a rock check dam and the aggregate can usually be spread along the channel bottom when the check dam is removed. Aggregate meeting the gradation requirements of 6A is recommended; use nothing finer than pea-stone. Maintenance Inspect check dams ...