Phosphorus Lake: A Snapshot of Fertilizer Fallout

Strip-mining Florida to fertilize the nation
or subscribe to access the full article.

J. Henry Fair

Phosphorus mining has a beneficial side and a disturbing side. It gives us ammonium phosphate, a key ingredient in the fertilizer used to grow abundant food. It also produces massive amounts of waste, depicted here.

The phosphorus comes from calcium phosphate rock that is strip-mined across several U.S. states and pulverized. Producers add sulfuric acid to form phosphoric acid, which is later converted to ammonium phosphate. Every ton of phosphoric acid generated creates five tons of a soil-like by-product, phosphogypsum. The white or gray substance emits radon gas and is therefore used in only a few applications, such as peanut farming. Most of the phosphogypsum is bulldozed for permanent storage into giant stacks that can reach 200 feet high and cover 400 acres or more. A gypstack contains one billion to three billion gallons of wastewater that gradually diffuses out, creating small lakes that shimmer blue or green as light bounces off bottom sediment. The water’s pH is between 1 and 2, corrosively acidic. The photograph shows the corner of one such stack in Florida and the lake beside it.

or subscribe to access the full article.
Buy Digital Issue $7.99
Print + Digital
All Access
$99.99 Subscribe
Rights & Permissions
Share this Article:


You must sign in or register as a member to submit a comment.

Starting Thanksgiving

Enter code: HOLIDAY 2015
at checkout

Get 20% off now! >


Email this Article