Section 321.40 - Concentrated Animal Feeding Operation (CAFO) Land Application Requirements(a) The purpose of this section is to describe the land application requirements that apply to concentrated animal feeding operations (CAFOs).(b) The land application of manure, sludge, or wastewater at agronomic rates and hydrologic needs shall not be considered surface disposal and is not prohibited.(c) Manure, sludge, or wastewater may be applied to the areas in the 100-year flood plain at agronomic rates not to exceed the hydrologic needs of the crop.(d) Discharge of manure, sludge, or wastewater from a land management unit (LMU) is prohibited and shall not cause or contribute to a violation of surface water quality standards, contaminate groundwater, or create a nuisance condition.(e) Irrigation practices shall be managed so as to minimize ponding or puddling of wastewater on the site, prevent tailwater discharges to waters in the state, and prevent the occurrence of nuisance conditions.(f) Land application shall not occur when the ground is frozen or saturated or during rainfall events unless in accordance with § 321.39(b)(3) of this title (relating to Operational Requirements Applicable to Concentrated Animal Feeding Operations (CAFOs)) or as approved by the commission.(g) The CAFO operator shall not locate a new LMU within the required well buffer zones identified in § 321.38(b) of this title (relating to Control Facility Design Requirements Applicable to Concentrated Animal Feeding Operations (CAFOs)), unless additional wellhead protective measures are implemented that will prevent pollutants from entering the well and contaminating groundwater. An exception to the full well buffer zone for a private drinking water well or a water well used exclusively for agricultural irrigation may be approved by the executive director if a licensed Texas professional engineer or licensed Texas professional geoscientist provides accurate documentation showing that additional wellhead protective measures will be or have been implemented that will prevent pollutants from entering the well and contaminating groundwater. Additional protective measures may include a sanitary seal, annular seal, a steel sleeve, or surface slab.(h) Vegetative buffer strips shall be maintained in accordance with Natural Resources Conservation Service (NRCS) Practice Standard Code 393. The minimum buffer shall be no less than 100 feet of vegetation to be maintained between manure, sludge, or wastewater application areas and water in the state. A buffer is not required for wastewater irrigation when applied by low-pressure, low-profile center pivot irrigation systems in areas of the state where the annual average rainfall is less than 25 inches per year. Land application of manure, sludge, and wastewater into surface water in the state is an unauthorized discharge and is prohibited.(i) CAFOs introducing wastewater or chemicals to water wellheads for the purpose of irrigation shall install backflow prevention devices in accordance with requirements contained in 16 TAC Chapter 76 (relating to Water Well Drillers and Water Well Pump Installers) and Chapter 290 of this title (relating to Public Drinking Water), as appropriate.(j) Nighttime application of manure, sludge, or wastewater by a CAFO shall be allowed only in areas with no occupied residence(s) within 1/4 mile from the outer boundary of the actual area receiving manure, sludge, or wastewater application. In areas with an occupied residence within 1/4 mile from the outer boundary of the actual area receiving manure, sludge, or wastewater application, application shall only be allowed from one hour after sunrise until one hour before sunset, unless the current resident owner or lessee of such residences have agreed in writing to specified nighttime applications.(k) Nutrient requirement. (1) Any land application of manure, sludge, and wastewater shall not exceed the planned crop requirements. Land application rates of manure, sludge, or wastewater shall be based on the total nutrient concentration, on a dry weight basis, where applicable.(2) Critical phosphorus level. Land application of manure, sludge, or wastewater shall not exceed the crop removal rate when results of the annual soil analysis for extractable phosphorus indicate:(A) a level greater than 200 parts per million (ppm) for a particular LMU; or(B) a level greater than 350 ppm for an LMU where the average annual rainfall is 25 inches or less and erosion control is adequate to keep erosion at the soil loss tolerance (T) or less and the closest edge of the field is more than one mile from a named stream; or(C) if ordered by the executive director to do so in order to protect water in the state.(3) Dairy CAFOs located in a major sole-source impairment zone shall develop a nutrient utilization plan (NUP) when the annual soil analysis for extractable phosphorus in zone 1 (0 - 6-inch incorporated; 0 - 2 or 2 - 6-inch if not incorporated) depth in an LMU is greater than 200 ppm. State-only CAFOs shall develop a NUP when the annual soil analysis for an LMU indicates the critical phosphorus levels in paragraph (2) of this subsection have been exceeded. A nutrient management plan, based on crop removal certified as meeting the NRCS Practice Standard Code 590 is equivalent to the requirements for a NUP.(A) If an operator is required to develop a NUP, the operator shall cease land application of manure, sludge, or wastewater to the affected area and may resume only after a NUP is implemented.(B) The NUP must be developed and certified by:(i) an employee of the NRCS;(ii) a nutrient management specialist certified by the NRCS;(iii) the Texas State Soil and Water Conservation Board;(iv) Texas AgriLife Extension Service;(v) an agronomist or soil scientist on full-time staff at an accredited university located in the State of Texas;(vi) a Certified Professional Agronomist certified through the certification program of the American Society of Agronomy;(vii) a Certified Professional Soil Scientist certified through the certification program of the Soil Science Society of America; or(viii) a licensed geoscientist-soil scientist in Texas after approval by the executive director based on a determination by the executive director that another person or entity identified in this subparagraph cannot develop the plan in a timely manner.(C) After a NUP is implemented, the operator shall land apply in accordance with the NUP until soil phosphorus is reduced below the critical phosphorus level. Thereafter, the operator of a dairy CAFO located in a major sole-source impairment zone shall implement the requirements of the nutrient management plan certified in accordance with § 321.36(c) of this title (relating to Texas Pollutant Discharge Elimination System General Requirements for Concentrated Animal Feeding Operations (CAFOs)) and the operator of other state-only CAFOs must follow the requirements in this section.(D) Land application under the terms of the NUP may begin 30 days after the plan is filed with the executive director, unless before that time the executive director has returned the plan for failure to comply with all the requirements of this subsection.(l) Runoff from an LMU. Where manure, sludge, or wastewater is applied in accordance with a site-specific nutrient management plan that complies with § 321.36(c) of this title or when the land application conforms to this section, precipitation-related runoff from LMUs is authorized as: (1) a pollutant discharge if the source is land associated with a CAFO in a major sole-source impairment zone; or(2) an agricultural stormwater discharge for all other sources.(m) Sampling and Testing. (1) Initial sampling. Before commencing land application of manure, sludge, or wastewater on LMUs and before resuming land application on LMUs where manure, sludge, or wastewater was not applied during the preceding year, the operator shall:(A) collect and analyze at least one representative sample of manure, sludge (if applicable), and wastewater for total nitrogen, total phosphorus, and total potassium;(B) collect and analyze at least one representative soil sample from each LMU according to the procedures in paragraphs (4) and (5) of this subsection; and(C) utilize the results of these analyses in determining application rates for manure, sludge, and wastewater.(2) Annual Sampling. The operator shall:(A) collect and analyze at least one representative sample of manure, sludge (if applicable), and wastewater for total nitrogen, total phosphorus, and total potassium;(B) collect and analyze at least one representative soil sample from each LMU where manure, sludge, or wastewater was applied during the preceding year according to the procedures in paragraphs (4) and (5) of this subsection; and(C) utilize the results of these analyses in determining application rates for manure, sludge, and wastewater.(3) The operator shall make the most recent nutrient analysis available to any recipient of manure, sludge, or wastewater.(4) Sampling procedures. The operator shall employ sampling procedures using accepted techniques of soil science for obtaining representative samples and analytical results.(A) Samples shall be collected using approved methods described in the agency's guidance RG-408 entitled "Soil Sampling for Concentrated Animal Feeding Operations."(B) Samples shall be collected by the operator or its designee and analyzed by a soil testing laboratory annually, except when crop rotations or inclement weather require a change in the sampling time. The pollution prevention plan shall contain documentation to explain the reasons for adjusting the sampling timeframe.(C) Obtain one composite sample for each LMU and per uniform soil type (soils with the same characteristics and texture) within the LMU.(D) Composite samples shall be comprised of 10 - 15 randomly sampled cores at a depth of zero to six inches.(5) Laboratory analysis. The operator shall have a laboratory analysis of the soil samples performed for physical and chemical parameters to include: nitrate reported as nitrogen in ppm; phosphorus (extractable, ppm, using Mehlich III extractant with Inductively Coupled Plasma analysis); potassium (extractable, ppm); sodium (extractable, ppm); magnesium (extractable, ppm); calcium (extractable, ppm); soluble salts (ppm) or electrical conductivity (deciSiemens/meter (dS/m) or millimhos/cm (mmhos/cm) determined from extract of 2:1 volume to volume (v/v) water/soil mixture); and soil water pH (soil:water, 1:2 ratio).30 Tex. Admin. Code § 321.40
The provisions of this §321.40 adopted to be effective April 1, 1987, 12 TexReg 904; amended to be effective September 18, 1998, 23 TexReg 9354; amended to be effective July 27, 1999, 24 TexReg 5721; amended to be effective July 15, 2004, 29 TexReg 6652; amended to be effective July 31, 2014, 39 TexReg 5786