Welcome To Whitehall Township Whitehall Township is located in the center of the Lehigh Valley. The Township is one hour north of Philadelphia and an hour and half from New York City.
SALINITY OVERVIEW Salinity is the concentration of dissolved salts in water, usually expressed in parts per thousand (ppt). Objects float higher in salt water than fresh water because salt water is denser (heavier per unit of volume).
So you can now understand what is a part per million. ppm in this context probably means parts per million. This is the concentration of a chemical or element in something like food or drink. for example 8 milligrams of mercury in 100 grams of fish would result in a mercury concentration of 0.8 ppm (parts per million)