If you look at the tabletop shaker experiments on the website, the water is cloudy because it is not being refreshed. In an open-system such as on a beach with water constantly refreshing, that would not be an issue.
The olivine can be placed on any shoreline or coastal area. The "tropical shelf-sea beach" set up we constantly refer to is simply the optimal and preferential solution. The main effects we are utilizing the beach for are that (1) the tumbling motion of the waves causes a constant abrasion that breaks up a silica coating that rapidly forms on exposed olivine and (2) the collision of grains on the shoreline causes smaller slivers to chip off, that themselves rapidly weather.
We want shelf-seas because the grains will be pulled off the beach and will continue to be weathered through underwater shear stress forces on the sea bed. Other locations work as well, but the olivine may take longer to weather if there is less motion, colder water, etc.