IMMAG - Iowa Manure Management Action Group

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June 2010 IMMAG Update

Welcome to the monthly update for the Iowa Manure Management Action Group (IMMAG) Web site. This update is provided as a service to inform you about changes made to the IMMAG Web Page or items of interest dealing with manure management and air quality from animal feeding operations. If you wish to subscribe to this mailing please click here. You may also view this update with direct links on the CURRENT NEWS site on IMMAG.


CURRENT NEWS: The Current News page on the IMMAG site is updated weekly. Please check this site often for the latest news regarding animal feeding operations and manure management issues.

Update on EPA and DNR activities in regards to Large CAFOs, Medium-Sized CAFOs and other issues regarding NPDES permits.
Recent aerial flyovers and compliance visits by EPA staff in Iowa have garnered a lot of attention from NW Iowa livestock producers. The following outlines the issues of major concern. It is imperative that you know how your livestock operation is defined by both the EPA and the DNR (see resource link below).  Please note, although there are examples provided that use certain species, these issues apply to all livestock species. You should also note the issues outlined below are not a result of new rule changes.

Resources: IMMS Vol. 1, Introduction to the Iowa Manure Manager Series

Implementation Guidance on CAFO Regulations – CAFOs That Discharge or Are Proposing to Discharge

Issue 1 Combined Livestock Operations and NPDES Permits.
While this issue is not a new, it does need to be revisited.  In April 2008, Iowa law came into compliance with federal law and required that animals of the same type, be counted together, across housing systems. Producers were given until December 31, 2008 to comply. So as example, if you have beef cattle confined in a deep-bedded system under roof, and you have beef cattle outside on an open lot, you must now add the beef cattle numbers together to determine if you meet the size requirement for a National Pollutant Discharge Elimination System (NPDES) permit. This also applies to other species such as swine. If you have a swine confinement and a few outdoor pigs (designated as the same type), you now count all of the animals together.

Resources:   For additional resources, including a list of animal types, and permit threshold requirements please see:
Iowa DNR Web Page

Fact Sheet NPDES Permits-Determining if a Combination Open Feedlot and Animal Confinement Must Apply for an NPDES Permit

Fact Sheet- Dairies Act Now

Take Note: When combining animal numbers across housing systems, it will be important you know what the definitions of adjacency/adjoin mean since you may have to count animals located at separate facilities.  See Issue 2 below.

Issue 2 How to determine if you have one animal feeding operation or multiple operations.
This is a complicated issue and not one in which everyone agrees. It would be in your best interest as a livestock producer to seek technical assistance from DNR to make this determination. Iowa law defines two or more livestock operations, under common ownership or management to be one animal feeding operation if they are 1) within 1,250 feet of each other and at least one of the sites was constructed after July 17, 2002, or 2) they use a common area or system for manure application. The EPA says two or more animal feeding operations under common ownership are classified as one operation if 1) they adjoin; or 2) they use a common area or system for manure application. Since EPA has no definition for "adjoin" they do consider two operations to be one operation if the operations are on two separate tracts of land, and there are no other owners with property between the two tracts.
Take Note: At this point in time, EPA is acknowledging Iowa’s 1,250 ft adjacency definition, but for example, if runoff/discharge occurs at an open lot(less than 1,000 beef animals), and you have more than 1,000 beef animals at another facility (permitted facility) they consider to "adjoin" the smaller feedlot, EPA will work with DNR to designate the smaller lot as a CAFO and an NPDES permit will be required for all animals at both sites.
Issue 3 Mixed species and the need for an NPDES permit.
In Iowa, by law, confinement facilities are not allowed to discharge so the DNR has contended that confinement facilities do not need NPDES permits (NPDES permits allow facilities to discharge under certain conditions). EPA’s CAFO laws require NPDES permits for any facility, open lot or confinement, if the facility meets permit threshold requirements (unless the facility proposes not to discharge). For now this is causing a lot of confusion with people thinking EPA is now counting animals across animal types and species. However, EPA maintains that if your swine confinement was large enough to require a NPDES permit (2,500 head of finishing hogs), that any other manure generated on the farm by other animals is now subject to NPDES permit requirements. So for example, if you have a 4,000 head swine confinement facility and you also have 50 beef cattle in an open lot, the swine confinement meets the permit threshold requirement to require a NPDES permit, even if the beef cattle do not and consequently all manure from the facility would fall under a NPDES permit. This would apply to any situation where the confinement or open lot meets the threshold numbers, and would require all manure sources on the farm to be included in the NPDES permit, no matter the number of type of animals. So as another example permit threshold sized operations that also have as few as 1-2 horses (not on pasture) or three 4-H steers on outdoor lots.

Resource: EPA  Producers’ Compliance Guide for CAFOs

Issue 4 Medium-Sized CAFOs.
The focus of the Iowa Plan for Open Feedlots and subsequent compliance enforcement has historically been targeted first at getting the Large open lot CAFOs into compliance. This did not preclude Medium- or Small- sized CAFOs. The laws have been on the books so to speak, but due to workload and budgets, the focus until now has been Large CAFOs.  It should be noted CAFOs of size less than a Large CAFO are now being investigated to determine if they meet CAFO status.  The definition of a Medium CAFO is as such:
1) it must meet the regulatory definition of an AFO; 2) meets the Medium threshold requirements for that animal type (see table below) and 3) it must meet at least one of the following "discharge criteria":

1) A man-made ditch, pipe, or similar device carries manure or process wastewater from the operation to surface water or 2) the animals come into contact with surface water that runs through the area where they’re confined.  If your operation falls into this category, you should consider immediate action to rectify the discharge criteria, or seek a permit.


EPA  Producers’ Compliance Guide for CAFOs

Issue 5 Man- made ditch criteria and road ditches.
The EPA considers road ditches to meet the definition of "man-made ditches" under the Medium CAFO requirements. If your animal feeding operation is discharging manure or process wastewater into a road ditch, or you are using the road ditch as part of your solids settling structure, you should consider immediate action to rectify this situation.
Issue 6 Stockpiles, Feed Storage, Chemical Storage and Mortalities

Facilities with NPDES permits are also required to address manure stockpiles, runoff from feed storage, chemical storage and mortalities.  If you have runoff from these practices/areas, you should consider immediate action to rectify the situation.


The IMMAG Events page is a compilation of manure management related events. Please check the events page often for new listings.

June 11. The Livestock and Poultry Environmental Learning Center will host the Webcast "Animal Ag’s Role in Greenhouse Gas Production: A Closer Look." The Webcast starts at 1:30 p.m. (central).  For more information click here.

July 9. The Livestock and Poultry Environmental Learning Center will host the Webcast "Planning for Manure Spills." The Webcast starts at 1:30 p.m. (central). Additional information will be posted as it becomes available.

July 15. 2010 Manure Expo "Balancing Production and Conservation" will be held at State College, PA. For more information please click here.

July 23. Manure Management Field Day for Small and Medium Sized Dairies and Feedlots. This field day will held near Boyden, Iowa. Details will be included on the IMMAG Events page as soon as they are available.



Angela Rieck-Hinz
2104 Agronomy Hall
Iowa State University
Ames, IA 50011
(515) 294-9590
Iowa Manure Management Action Group

Manure sampling - Click on photo to enlarge

Manure sampling.


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