9 POLYTETRAFLUOROETHYLENE (PTFE) PIPE; POLYVINYL CHLORIDE (PVC) MONITORING SCREENS AND CASINGS; PTFE MONITORING SCREENS AND CASINGS; STAINLESS STEEL MONITORING CASINGS; PVC AND POROUS MEDIUM PIEZOMETERS; VARIABLE CAPACITY BAILERS MADE OF PVC, PTFE, LEXAN OR STAINLESS STEEL AND ASSOCIATED ACCESSORIES; PVC AND PTFE AIR OR GAS LIFT SAMPLERS AND ASSOCIATED EQUIPMENT; PVC, PTFE AND STAINLESS STEEL BLADDEER PUMPS; ELECTRICALLY OPERATED MODULAR SEQUENCE TIME CONTROL UNITS; PVC AND PTFE TRANSFER VESSELS; PTFE DISK LYSIMETERS; VACCUM PRESSURE, SLEEVE AND CASING LYSIMETERS MADE OF PVC OR PTFE; MONITORING WELL CENTRALIZERS; SILICA FLOUR FOR LYSIMETER INSTALLATION; PVC WASHDOWN VALVES; ALL FOR USE IN THE CREATION AND OPERATION OF GROUND WATER QUALITY MONITORING WELLS