Tag: sediment

Acid Rich Soils in Englishtown, NJ

Check out these pics from June 16, 2016 water quality monitoring in the Englishtown area of the LRW. Waters were bright orange in color with very low pH (3.8):

OLYMPUS DIGITAL CAMERA

Upstream was an eroding bank with charcoaled, black wood:

Englishtown - black wood, acidic soils 6.16.16

What’s going on here? This is an acid-producing deposit from the Englishtown Geologic Formation. According to Stephanie Murphy, Director of Rutgers Soil Testing lab: “When deposits are buried (not exposed) the mineral is iron sulfide and pH is not “unusual”. It can have black color. When exposed, the extreme acidity results from certain microbes oxidizing the sulfide to sulfate with H+ produced. Same process with acid coal-mining spoils. Acidity makes iron soluble, and when it re-deposits/precipitates, you get the orange hues.”

Also see the NJ Geological Survey’s Figure 1-1. NJ sedimentary units with potential to produce acid:

http://www.state.nj.us/dep/njgs/geodata/dgs09-2.htm