Abstract: A core catcher comprising: a cap configured to be secured to a first end of a core liner such that when the first end of the core liner is inserted into sediment a sample sediment core enters the core liner through the cap; a cross-beam coupled to the cap and mounted across the first end of the core liner such that a cross-section of the first end of the core liner is divided into two openings; a flexible member secured to the cross-beam such that the flexible member, the cross-beam, and the cap form a dual-flap valve designed to allow the sediment core to enter the core liner through the two openings and to prevent the sediment core from escaping the core liner through the cap.

Abstract: A core catcher comprising: a cap configured to be secured to a first end of a core liner such that when the first end of the core liner is inserted into sediment a sample sediment core enters the core liner through the cap; a cross-beam coupled to the cap and mounted across the first end of the core liner such that a cross-section of the first end of the core liner is divided into two openings; a flexible member secured to the cross-beam such that the flexible member, the cross-beam, and the cap form a dual-flap valve designed to allow the sediment core to enter the core liner through the two openings and to prevent the sediment core from escaping the core liner through the cap.

Abstract: A system includes a plurality of chamber holders having openings therein, and an exposure chamber positioned in each chamber holder. Each exposure chamber includes a mesh portion and a top end cap. One exposure chamber contains a mesh bottom and one contains a closed bottom. Each chamber holder is positioned within an opening contained within a base portion. One exposure chamber may extend beyond the lower boundary of the base portion. A top portion may be secured to the base portion to contain the chamber holders. A pump, with connected supply hose, may be coupled to the top portion. The supply hose is routed through the chamber holders such that a supply hose opening is adjacent to each chamber holder. The system may include a water quality sensor and a passive sampling device coupled to the base portion. A deployment system may be connected to the top portion.