Method and apparatus for sampling low-yield wells

An apparatus for collecting a groundwater sample from a low-yield well comprising:

• a reservoir substantially devoid of air;
• a pump for removing water from a well in a low-yield aquifer and providing the water to the reservoir;
• at least one sensor;
• a controller for activating and deactivating the pump, the controller activating the pump at a flow rate less than about 500 ml/mm in response to signals received from the sensor;
• wherein the controller activates the pump when the water level in the well reaches a first level as indicated by the at least one sensor, and the controller deactivates the pump when the water level in the well reaches a second lower level as indicated by the at least one sensor.

An apparatus for collecting and storing a sample from a low-yield well for subsequent analysis comprising:

• a sample reservoir substantially devoid of air for receiving a volume of liquid for subsequent monitoring;
• a pump for removing liquid from a low yield well and providing the liquid to the sample reservoir;
• a controller for automatically activating the pump to fill the reservoir;
• at least one fluid level sensor adapted to sense the level of liquid in the well and output at least one signal;
• at least one reservoir sensor to sense the volume of liquid in the reservoir;
• wherein the controller sequentially activates and deactivates the pump in response to the at least one signal until the reservoir is filled with a predetermined volume of liquid as indicated by the at least one reservoir sensor.

An apparatus for collecting a sample from a well comprising:

• a sample reservoir for receiving a volume of liquid for subsequent monitoring;
• a sample bypass conduit;
• a pump for removing liquid from the well and providing the liquid to the sample reservoir;
• a multiway valve having a first position placing the pump in fluid communication with the sample reservoir and a second position placing the pump in fluid communication with the bypass conduit;
• a controller for automatically activating the pump and the multiway valve;
• at least one fluid level sensor adapted to sense the level of liquid in the well and output at least one signal;
• wherein the controller sequentially activates and deactivates the pump in response to the at least one signal until the reservoir is filled with a predetermined volume of liquid.

An apparatus for collecting a groundwater sample comprising:

• a reservoir;
• a pump for removing water from a well and providing the water to the reservoir;
• at least one sensor operable to sense the level of water in the well;
• a controller for activating and deactivating the pump in response to signals received from the at least one sensor wherein the controller activates the pump when the water level in the well reaches a first level as indicated by the at least one sensor and the controller deactivates the pump when the water level in the well reaches a second lower level as indicated by the at least one sensor;
• and
• a multiway valve in fluid communication between the pump and the reservoir and controlled by the controller for selecting between purging the well and providing the water to the reservoir.