On Monday, February 10, 2014, The Equiery reported on the composting regulations being proposed by the Maryland Department of the Environment. These comprehensive regulations cover all types of composting facilities, not just ag related. Nevertheless, ag related composting – which is already monitored by The Soil Conservation Districts and the Department of Agriculture, would now also be subjected to regulation by the Department of the Environment, were these proposed regs to be adopted.

Below are excerpts from The Maryland Horse Council’s comments, written by president Jane Seigler, to MDE. Click here to read MHC’s review in full.

The proposal would establish a broad and complex new scheme for regulating composting facilities, which – at least in the non-farm context – have been largely unregulated previously. However, agricultural composting has been facilitated and overseen by the Maryland Department of Agriculture (MDA) and the local Soil Conservation Districts for decades, and that history and practice should be used to inform how these new MDE regulations would affect agricultural composting, especially where manure is the primary feedstock.

As we understand it, under MDE’s proposal on-farm composting facilities must be permitted unless:

1) the composted material is produced and used on-site or at a facility controlled by the same operator, (hereinafter “on-site”) (section .05 B (2)), or

2) the composting facility is located on a farm that is required to register with MDE because it uses greater than 5000 square feet “in support of composting,” accepts materials from off-site, and uses that compost on-site (section .05 B (3)), or

3) is a Tier 1 (primarily yard waste) or Tier 2 facility (certain other materials including animal manure and bedding) under 5000 square feet “in support of composting,” that complies with certain specified general environmental standards and whose windrows or piles are lower than 9 feet (Section .05 B (04)). It is not clear whether this particular provision also includes horse farms that compost animal manure and bedding, or whether it is intended to refer only to non-farm Tire 1 and Tier 2 facilities. This confusion is also implicated in the provisions of section .11 (General Permits)

MHC respectfully submits that the proposed regulations fail to take into account the unique characteristics of composting as it typically occurs on horse farms.

    • Many horse farms compost the manure and bedding that is removed from barns and sheds during regular cleaning. This material is produced on-farm, although the straw, wood shavings or other bedding material is typically purchased off-site. Although the proposed regulations state that manure including bedding is a Type 2 feedstock, they do not make clear whether use of bedding that is purchased off-site would preclude application of exemptions for feedstocks produced on-site. The regulations should be clarified to state that animal manure that contains animal bedding used on-site (regardless of its source) constitutes a feedstock that is produced on-site.
    • According to NRCS information, a 23 horse operation will use an 80’ x 60’(4,800 sq ft) pad for 180 days composting capacity. Thus, any operation with 24 or more stalled horses will require a pad of greater than 5,000 square feet. There are dozens, if not scores of horse farms in Maryland that meet this threshold. The proposed regulations should be amended to increase the 5,000 square foot limit to accommodate larger horse operations.
    • The proposed regulations do not discuss what is perhaps the most typical model for horse farm composting operations, i.e., only on-farm generated materials (manure and bedding) are composted, and the resulting compost is sold or given away to other local farms, residences, landscapers, etc. The regulations should be amended to make clear that composting facilities that use only materials generated on-site, but distribute them off-site are exempt from the permitting requirements as long as they are in compliance with applicable MDA regulations.
    • In some cases, horse farms take in manure from other farms not owned or controlled by them, who do not have the capacity to compost their own manure. These facilities may distribute the final composted material to other farms, residences or landscape companies. The regulations should be amended to increase the 5,000 square foot limit for these facilities to, for example, 40,00 square feet as consistent with the Forest Conservation Act, and exempt them from the permitting requirement as long as they are in compliance with applicable MDA regulations.



Composted horse manure is a valuable and as yet under-utilized resource. According to a 2010 equine census,* Maryland is home to 79,100 equine animals housed at 16,000 locations with 188,000 acres devoted strictly to horses.  At an average rate of 55 pounds of manure excreted per horse per day,** Maryland’s horses produce an estimated 1,443,575,000 lbs of manure per year. Horse manure is a good substrate to use for compost.  First, it’s drier than other livestock feces, therefore it’s easier to transport from one location to another.  Second, it has a 5:1:2 ratio of nitrogen, phosphorous, potassium** and thus is relatively balanced in nutrients when it’s applied as a soil amendment.  Third, when the feces include animal bedding products such as sawdust or wood shavings it is close to an ideal 25:1 carbon to nitrogen ratio.

It is in the best interest not only of horse farm owners, but of all Maryland citizens and of our environment to ensure that this product is recycled to its highest and best use, by minimizing barriers to that use. Unreasonable restrictions on manure composting and distribution of the composted end product as a soil amendment will only result in more manure ending up in landfills, rather than benefitting our soils, crops, gardens and roadsides.