LAC 7:XI.143 – Gypsum; Requirements for Agricultural Use; Analytical Tolerances

A. To use by-product gypsum (phosphogypsum and flue gas desulfurization gypsum) in accordance with R.S. 3:1424, the following shall apply:
1. 1. The provider of the gypsum shall furnish chemical analysis documentation, from an accredited laboratory, for the product to the producer.
2. 2. The chemical analysis documentation shall include the calcium and sulfur content and content of elements listed in Table 1 of the most recent version of the Conservation Practice Standard, Amending Soil Properties with Gypsum Products, Code 333 as published by the Natural Resources Conservation Service of the United States Department of Agriculture. Concentrations of these elements shall not exceed maximum allowable concentrations listed in Table 1 of that publication. In addition, the radium-226 concentration in the gypsum-containing product shall not exceed 10 picocuries per gram (pCi/g) and chloride content shall not exceed one-half of one percent (0.5 percent).
B. The agricultural producer shall use gypsum only on his land or with written authorization from the landowner once the gypsum is analyzed and passes all analytical tolerances established by the department.

AUTHORITY NOTE: Promulgated in accordance with R.S. 3:1424.

HISTORICAL NOTE: Promulgated by the Department of Agriculture and Forestry, Office of the Commissioner, LR 52:24 (January 2026).