Animal Manure Storage: Assessing Drinking Water Contamination Risk

For each category listed on the left that is appropriate to your situation, click the box under rank 1-4 that best applies. Your "rank number" will then be genrated on the right.

Glossary for this Fact Worksheet

Information for this Fact Worksheet (PDF)

 

Please Select Your County:

Long-Term Storage (180 days or more) (Addressed in Section 1)
 
Low Risk
(rank 4)
Low-Mod Risk
(rank 3)
Mod-High Risk
(rank 2)
High Risk
(rank 1)
Your Rank

1. Manure storage pond (below ground)

or

 Designed and installed according to accepted engineering standards and specifications. Properly maintained. Water table deeper than 20 feet. Built to post-1985 standards. Designed and installed according to accepted engineering standards and specifications. Properly maintained. Water table deeper than 20 feet. Built to pre-1985 standards. Not designed to engineering standards. Constructed in medium or fine-textured dense materials (silt loam, loam, clay loams, silty clay). Water table deeper than 20 feet. Earthen lining eroding. Not designed to
engineering standards. Constructed in
coarse-textured materials (sands, sandy loam). Fractured bedrock or water table shallower than 20 feet. More than 10 years old. Earthen lining
perforated.

 

 

Steel, glass-lined
(liquid-tight design, above ground)

or

 Designed and installed according to accepted engineering standards and specifications. Properly maintained. Designed and installed according to accepted engineering standards and specifications. Not
maintained.		 Leaking tank on
medium-textured soils
(silt loam, loam).		 Leaking tank on
coarse-textured soils (sands, sandy loam). Water table or fractured bedrock shallower than 20 feet.

 

 

Concrete stave
(liquid-tight design)

or

 Designed and installed according to accepted engineering standards and specifications. Properly maintained. Designed and installed according to accepted engineering standards and specifications. Not
maintained.		 Concrete cracked,
medium-textured soils (silt loam, loam). Water table deeper than 20 feet.		 Concrete cracked,
coarse-textured soils (sands, sandy loam). Water table or fractured bedrock shallower than 20 feet.

 

 
Poured concrete (liquid-tight design) Designed and installed according to accepted standards and
specifications. Properly maintained.		 Designed and installed according to accepted engineering standards and specifications. Not
maintained.		 Concrete cracked,
medium-textured soils (silt loam, loam). Water table deeper than 20 feet.		 Concrete cracked,
coarse-textured soils (sands, sandy loam). Water table or fractured bedrock shallower than 20 feet.

 

 

Short-Term Storage (usually 30-90 days; in some cases, up to 180 days) (Addressed in Section 2)
2. Stacked in field (on soil base) --- --- Stacked on high ground. Medium or fine-textured soils (silt loam, loam, clay loams, silty clay). Water table is deeper than 20 feet. Stacked on high ground or floodplain. Coarse-textured soils (sands, sandy loam). Fractured bedrock or water table shallower than 20 feet.

 

 

 

 
3. Stacked in lot Covered concrete lot with curbs, gutters, and settling basin. Concrete lot with curbs and gutters. Grass filter strips installed and
maintained.		 Earthen lot with medium or fine-textured soils (silt loam, loam, clay loams, silty clay). Water table deeper than 20 feet. Earthen lot with
coarse-textured soils (sands, sandy loam). Fractured bedrock or water table shallower than 20 feet.

 

 
4. Water-tight
structure 		Designed and installed according to engineering standards. All liquids retained. Designed and installed according to engineering standards on medium and fine-textured soils (silt loam, loam, clay loams, silty clay). Water table deeper than 20 feet. Designed and installed according to engineering standards on
coarse-textured soils (sands, sandy loam). Water table or fractured bedrock shallower than 20 feet.		 Designed and installed according to engineering standards. Not properly maintained. Water treatment and diversion and terrace structures allowed to deteriorate.

 

 
5. Stacked in open housing Building has concrete floor, protected from surface water runoff. Adequate bedding
provided.		 Building has earthen
or concrete floor on medium or fine-textured soils (silt loam, loam, clay loams, silty clay),
protected from surface water runoff. Water table deeper than 20 feet.		 Building has earthen or concrete floor on medium or fine-textured soils (silt loam, loam, clay loams, silty clay), subject to surface water runoff. Water table or fractured bedrock shallower than 20 feet. Building has earthen floor on coarse-textured soils (sands, sandy loam), subject to surface water runoff. Water table or fractured bedrock
shallower than 20 feet.

 

 
6. NO STORAGE (Hauled off farm or spread in less than 30 days) Hauled off farm for proper storage. Daily spreading. --- Site not designed for manure storage.

 

 

 

Location (Addressed in Section 3)
7. Location of
animal manure storage in relation to drinking water well		 Manure stack or earthen manure storage pit more than 400 feet from well. Manure storage structure (liquid tight) more than 200 feet from well. Manure stack or earthen manure storage pit more than 250 feet from well. Manure storage structure (liquid tight) more than 100 feet from well. Manure stack or earthen manure storage pit less than 250 feet down-slope from well. Liquid-tight manure storage structure less than 50 feet
down-slope from well.*		 Manure stack or earthen manure storage pit less than 250 feet upslope from well. Liquid-tight manure storage structure less than 50 feet upslope from well.*

 

 

Manure Application Site (Addressed in Sections 4 and 5)
8. Separation distance and site conditions Incorporated into
unfrozen, unsaturated soil, or applied at site with heavy vegetation more than 200 feet from wellhead.**		 Incorporated into
unfrozen, unsaturated soil, or applied at site with heavy vegetation less than 200 feet from wellhead.**		 Applied to unfrozen, unsaturated soil with no incorporation and little vegetation 200-500 feet from wellhead. Applied to frozen,
saturated, or snow covered soil. Applied to site with no incorporation and little vegetation less than 50 feet from wellhead.

 

 
9. Application rate Applied at rate of
available nutrients equal to or less than plant needs based on soil test.** Annual application less than 250 pounds available nitrogen or less than 20 dry tons of solid waste per acre.		 Low rates of application used with no soil tests performed.** Annual application less than 250 pounds available nitrogen or less than 20 dry tons of solid waste per acre. High rates of application used with no soil tests performed. Rate may exceed plant needs. No farm nutrient management plan. Applied at rate greater than plant needs. Annual application more than 250 pounds available nitrogen or more than 20 dry tons of solid waste per acre.

 

 
*Not allowed by most planning and zoning boards. Existing wells must meet separation requirements in effect at time of construction.
**Applied at the times and rates specified in the farm nutrient management plan.
Boldface type in high risk column: Besides representing a higher-risk choice, this practice also violates Idaho law.