Manure Lagoon Cleanout: Agitation, Pumping, and Dredging
For the pumping and application side of a lagoon cleanout, most of the Hoover Ag manure equipment lineup applies.
The following guide is educational—a plain-language summary of the rules as they currently stand, with sources cited so you can go deeper on anything that matters for your operation. It is not legal advice, and it isn’t a substitute for working with a certified nutrient management planner or your county conservation district. Regulations change. When you’re making a real compliance decision, work with a specialist.
Pennsylvania’s regulatory framework is built on the principle that anyone applying manure or agricultural process wastewater to land needs to be doing it under a written plan. That includes small operations, large ones, and everyone in between.
The specific plan depends on the size and type of your operation. There are three that cover almost every situation.
Manure Management Plan (MMP). The baseline plan required for essentially all agricultural operations that apply manure or agricultural process wastewater. It’s built around the standards in the Pennsylvania Department of Environmental Protection’s Manure Management Manual. If you’re a smaller operation without a permit under a different program, this is your plan.
Act 38 Nutrient Management Plan. Required for Concentrated Animal Operations (CAOs) under Pennsylvania’s Nutrient Management Act (Act 38). CAOs are farms with high animal densities, generally more than 2 animal equivalent units (AEUs) per acre on an annualized basis and more than 8 AEUs total. Act 38 plans are more detailed than MMPs and must be written by a certified specialist.
CAFO permit. Concentrated Animal Feeding Operations, which is a federal designation under the Clean Water Act, have to hold a permit through PA DEP. CAFO thresholds are based on animal numbers set by the EPA. Most CAFOs also fall under Act 38.
The Bucks County Conservation District has a plain-language summary of who falls into which category, and Penn State Extension’s Manure Management Manual Program page is the definitive resource for figuring out which plan you need.
The terminology matters because it decides which plan you need and how strict the rules are.
Animal Operation (AO). A farm below the CAO threshold. Uses a Manure Management Plan.
Concentrated Animal Operation (CAO). Above 2 AEUs per acre and above 8 AEUs total. Uses an Act 38 Nutrient Management Plan.
Concentrated Animal Feeding Operation (CAFO). Federal designation based on animal numbers. Requires a NPDES permit through PA DEP and typically also an Act 38 plan.
An AEU is 1,000 pounds of live animal weight, so a mature dairy cow is roughly one AEU. A 100-cow dairy on 40 acres is at 2.5 AEU/acre and above the CAO threshold. A 100-cow dairy on 80 acres is at 1.25 AEU/acre and below it. PA DEP publishes an AEU calculator that walks you through the math for your specific animals.
Setback distances from sensitive areas are the piece of the regulations most operators run into on a daily basis. The numbers below come from Penn State Extension’s summary of Pennsylvania Manure Application Setbacks and Requirements, which pulls from Act 38 regulations and the Manure Management Manual.
From streams, lakes, and ponds. Under a Manure Management Plan, the standard setback is 100 feet, with reductions available if certain conservation practices are in place. A 50-foot setback is available if the current soil test is below 200 ppm phosphorus, no-till practices are used, and cover crops are planted when residue is removed. A 35-foot setback is available with a permanent vegetative buffer. Act 38 plans have similar options but different specifics.
From private wells, springs, and public water wells. 100 feet, or larger if a wellhead protection authority requires it.
From open sinkholes. 100 feet, with a 35-foot option under Act 38 if a permanent vegetative buffer is in place.
From above-ground inlets to agricultural drainage systems. 100 feet for winter application where surface flow is toward the inlet.
In concentrated water flow channels. Application in swales, gullies, or ditches is either explicitly prohibited (under the Manure Management Manual) or strongly discouraged (under Act 38).
Every field on the operation that touches a sensitive area has to have those setbacks mapped on the farm map that goes with the plan.
Winter is the strictest window in the regulatory calendar. It’s defined as any of three conditions: the calendar window from December 15 to February 28, ground frozen four inches deep or more, or ground snow-covered. Any of the three triggers winter rules regardless of the calendar date.
Winter application is discouraged but not banned. If you spread in winter, you have to meet all of these:
Application rate limits are also lower in winter. Maximum winter rates are 5,000 gallons per acre of liquid manure, 20 tons per acre of solid non-poultry manure, or 3 tons per acre of solid poultry manure.
Penn State Extension has a detailed guide on winter spreading. If your operation is doing much winter application, that’s worth reading in full.
Injection is generally the recommended approach when it can be done safely. Placing manure below the surface keeps it in place through snowmelt and reduces runoff risk sharply. If you’re regularly applying in winter and want to expand your options, a dragline injector can change what compliance looks like.
Act 38 plans have specific fall application requirements aimed at reducing off-season nutrient loss. Fall applications require either:
The Manure Management Manual doesn’t spell out fall requirements as strictly for MMP-only operations, but the same practices are strongly encouraged.
Maximum application rate in a single pass, under any plan type, is 9,000 gallons per acre of liquid manure. You can apply more overall, but not in a single pass. Ground has to dry between passes.
Total application rates over the year are governed by the nutrient balance sheet in your plan. In simple terms, you can’t apply more nutrients than the crop can use, based on soil tests and expected yield.
Manure storage facilities have their own set of rules under 25 Pa. Code § 91.36. The short version is that any manure storage facility has to be designed, built, and operated to prevent discharges to surface water, even during a 25-year, 24-hour storm. Liquid or semi-solid storage facilities built after January 29, 2000 either need a water quality management permit or need to be certified by a registered professional engineer as meeting the Manure Management Manual and Pennsylvania Technical Guide standards.
If you hire someone to spread manure for you (a custom applicator), that person has to be certified as a commercial manure hauler under Act 49. Certification is administered under 7 Pa. Code Chapter 130E and involves training and testing. When you hire a hauler, ask to see their certification.
If you’re the operator and you’re hauling your own manure to your own fields, Act 49 doesn’t apply. Act 49 covers commercial haulers moving manure for third parties.
Enforcement in Pennsylvania is mostly complaint-driven and complaint-followed-by-inspection. If a neighbor reports a runoff event, if a stream shows signs of contamination downstream of your operation, or if DEP has reason to inspect (during a permit renewal, for instance), an inspector will look at your plan and your practices.
Penalties depend on the violation. Missing plans, plans that don’t meet requirements, application outside plan parameters, and setbacks violations can all trigger corrective action orders, civil penalties, or requirements to install additional practices. Operations under Act 38 with an approved plan get some liability protection against nuisance suits (this is one of the reasons about 90 percent of Act 38 plans in Pennsylvania are held by farms that would not be required to have them).
If you’re not sure which plan type you need, or what your setbacks and application windows look like, three good starting points:
Regulations don’t tell you what equipment to buy, but equipment choice affects what compliance looks like day to day. Two examples.
Injection expands your options. Dragline injection equipment that places manure below the soil surface reduces runoff risk, which can affect setback flexibility in Act 38 planning and reduces exposure during winter application. The nutrient retention benefits also improve the numbers on your nutrient balance sheet.
Surface tools like a dribble bar do a lot better than splash plates. The Hoover Ag 50 foot dribble bar places manure in controlled streams at the soil surface, which reduces the odor and volatilization losses that make surface application more compliance-sensitive.
Neither piece of equipment is a substitute for a plan. But for operations where the plan is tightening around application method, the equipment side of the conversation matters.
If you want to talk through what fits your operation and your plan, call Hoover Ag at (610) 468-9666 or get in touch. Take a look at the manure equipment lineup for what we build in Pennsylvania.
Sources:
For the pumping and application side of a lagoon cleanout, most of the Hoover Ag manure equipment lineup applies.
Biosolids land application follows a chain of custody and compliance that starts at the wastewater treatment plant and ends at the field.
A well-designed low-speed bedding spreader will handle damp, caked, and matted bales as a matter of routine.