1. Glauconite (Greensand)
A Peculiar Soil Constituent
Fred H. Bowers, Ph.D., Princeton Soil Institute

2. What is Glauconite? Called Greensand Marl
Sand-size particles or pellets (See figures below)
Normal sand sized particles consist of discrete minerals such as quartz, orthoclase, calcite, etc.
Glauconite sand-size particles are made up of relatively stable pellets of clay-size mica (Clay).
The pellets generally range from about 0.5 to 0.05 mm in diameter with some being as much as 4 mm cemented with clay-size siderite.
Produces good structure when undisturbed

3. Distribution
New Jersey has some 325,000 acres of greensand (glauconite-bearing) soils

4. Water and Nutrient Characteristics
Water Holding Character
NUTRIENTS: Contains up to about 7-8% potash (K2O) and, in some instances, a little more (Hower, l.c.).
Table 1. Quantity of Moisture Retained in Various Soils and Greensand Deposits at Two Tension Levels (unpublished data of Prof. N. A. Willits).
Soil
6 Atm Tension % Moisture
15 Atm Tension % Moisture
Sassafras
2.3
1.3
Hornerstown 20
16.4

5. Effects of Glauconite on Septic System Functionality
Tricky Evaluations (due to texture by hand)
Mottling
Enhanced due to moisture holding
Oxidation of reduced iron on peds
Construction
Smearing when constructing with backhoe
Do it by hand
Clogging and chemical changes
Susceptible to deflocculation from salts from water softener backwash

6. Soils of Glauconite Areas
Freehold
Collington
Colts Neck
Adelphia
Marlton
Kresson

7. How to Ensure a Functioning Septic System in Glauconite
Standard septic tank fields
Mottling can suggest SHWT but not be accurate. Look at soil series. Look at associated vegetation; Obtain a soil scientist when in doubt
Design disposal field as if it were clay (K class K0 for under-drain requirements)
Do not smear or alter the glauconite. Dig trenches by hand.
Drip irrigation into the upper soil horizons that avoid flooding
Lay down a layer of ASTM 33 sand on the glauconite to form the biomat and form transition to clay
Avoid using water softeners