A large east coast municipality continually generates 150 to 200 wet tons of biosolids per day, seven days a week, 365 days per year. Beneficial use via land application was identified as the best alternative to disposal in an east coast regional landfill. The major issue along the east coast is obtaining large quantities of land for biosolids application. The municipality recently identified areas in the Western US to land apply biosolids. The biosolids will be shipped by railcars to western locations. The transportation costs, believe it or not, are overall cheaper than landfilling on the east cost. You have recently been contacted to serve as a consultant by Mr. Jim Shortz, a dryland wheat farmer in Southeastern Colorado who has approximately 50,000 acres of land and is considering to use biosolids as a substitute for nitrogen to fertilize his crop. If he chooses to land apply bioslids, he will sign a 30 year contract with the biosolids generator.
Mr. Shortz is a very curious farmer, wondering if biosolids land application will enhance or degrade his farm’s soil.
NOTE: The following series of questions are designed to help you think about the interactions among soils, plants, and hydrology when applying any type of organic waste to soil. While some of the observations you make will be specific to the actual physical land application site, many could be generalized to very different locations anywhere in the world. Please continue with the lesson.
He has looked up some information about his soil on the Natural Resource Conservation Services website, and gives you the following table:
Mr. Jim Shortz’s Farm and Soil Characteristics
Semi-arid, with an average 10 inches (25 cm) of rainfall per year and an average temperature of 63 °F (17 °C) (see Soil Genesis and Development, Lesson 2.1 - Processes of Weathering - Introduction)
|Mollisol (see Soil Genesis and Development, Lesson 5.6 - Mollisols)|
Soil Chronological Age
|2000 years old (see Soil Genesis and Development, Lesson 4.4 - Soil Horizon Development)|
|Soil Organic Matter Content||Less than 1% (see Soil Genesis and Development, Lesson 4.3 - Soil Profiles and Horizons)|
|Topography||Relatively Flat (see the photo of his land on the previous page of this lesson, read more in Soil Genesis and Development, Lesson 3.5 - Topography’s Effect on Soil Formation)|
|Soil Parent Material||Alluvium (see Soil Genesis and Development, Lesson 3.6 - How Parent Material Affects Soil Profile Development and this Types of Parent Material PowerPoint Presentation)|
|Rock Type which Fomed Soil||Sandstone (see Soil Genesis and Development, Lesson 1.4 - Sedimentary Rocks)|
|Soil Depth to Parent Material||Greater than 60 inches (150 cm)|
|Vegetation Prior to Becoming a Farm||Grassland Vegetation|