30 Tex. Admin. Code § 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 operation (CAFO) general or individual water quality permits or other authorizations allowed by this subchapter.
(b) The land application of manure, litter, or wastewater at agronomic rates and hydrologic needs shall not be considered surface disposal and is not prohibited.
(c) Manure, litter, 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, litter, or wastewater from the 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 Control Facility 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)). 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 no less than 100 feet of vegetation to be maintained between manure, litter, 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. The CAFO operator shall maintain the buffer strips in accordance with Natural Resources Conservation Service (NRCS) guidelines.
(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).
(j) Nighttime application of manure, litter, 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 LMU receiving manure, litter, or wastewater. In areas with an occupied residence within 1/4 mile from the outer boundary of the LMU receiving manure, litter, or wastewater shall only be allowed from one hour after sunrise until one hour before sunset, unless the current occupants of such residences have, in writing, agreed to such nighttime applications.
(k) Any CAFO operator who owns, operates, controls, rents, or leases land where manure, litter, or wastewater from the CAFO is land applied must be in compliance with the deadline and requirements specified in §321.36(d) of this title (relating to Texas Pollutant Discharge Elimination System General Requirements for Concentrated Animal Feeding Operations (CAFOs)). Before this deadline, the operator of any existing CAFO must manage nutrients on LMUs according to all other applicable requirements of this subchapter.
1. (1) Nutrient requirement. Any land application of manure, litter, and wastewater shall not exceed the nutrients necessary to meet the planned crop requirements. Land application rates of manure, litter, and wastewater shall be based on the total nutrient concentration on a dry weight basis.
2. (2) Critical phosphorus level. A permit or other authorization shall establish the appropriate threshold for phosphorus in the soil and the requirements to develop the nutrient utilization plan (NUP). If an operator is required to develop a NUP, the operator shall cease land application of manure, litter, or wastewater to the affected area and may resume only after a detailed NUP has been implemented.
3. (3) NUP. An NMP (Practice Standard 590) certified as meeting the NRCS standard is equivalent to the requirements for a NUP. The NUP, based on crop removal, must be developed and certified by an employee of the NRCS, a nutrient management specialist certified by the NRCS, the Texas State Soil and Water Conservation Board, Texas Cooperative Extension, an agronomist or soil scientist on full-time staff at an accredited university located in the State of Texas, or a professional agronomist or soil scientist certified by the Certified Professional Agronomist certified through the certification program of the American Society of Agronomy, a Certified Professional Soil Scientist certified through the certification program of the Soil Science Society of America, or 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 paragraph cannot develop the plan in a timely manner. 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 CAFO shall implement the requirements of the nutrient management plan certified in accordance with §321.36(d) of this title. All other CAFOs must follow the requirements in this section.
4. (4) For a CAFO, 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.

Source Note: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.