Groundwater Assessment

Literature Review: Manure and Groundwater Quality

In support of Ecology's Water Quality Program concentrated animal-feeding operations (CAFO) permit renewal, this report reviews current scientific information on manure management to present strategies for measuring the effectiveness of these management practices.

This report summarizes information presented in the literature in the following areas:

  1. Documented impacts to groundwater quality.
  2. Effectiveness of manure management practices; including application rates, crop uptake, soil mechanics, irrigation water management, and storage lagoon design.
  3. Potential risks of manure management to impact groundwater.
  4. Sampling protocol for crops, manure, soil, groundwater, and mass balance calculations.
  5. Tools to assess manure management effectiveness, quantify available nitrogen, and determine application rates and times.
  6. Evaluating impacts to groundwater quality using site specific soil nitrate threshold limits and groundwater monitoring.

Concentrated Animal Feeding Operation General Permit is a page about the permit.


Manure and Groundwater Quality, Literature Review

For more information:

Melanie Redding, melanie.redding@ecy.wa.gov, (360) 407-6524