An operator who uses chemical fertilizer, animal manure, or biosolids, as provided in Regulation .04A of this chapter, shall have a nutrient management plan that shall: Be prepared by a certified nutrient management consultant or by the farm operator, if certified in accordance with this subtitle; Be prepared according to the schedule set forth in Regulation .04A or B of this chapter by using the limiting nutrient determination described in COMAR 15.20.08.05E; and Address the following existing factors: All aspects of the agricultural operation, including tillage, cropping, pasture, or production of an agricultural product, such as plants, trees, sod, food, feed, animals, and fiber; Identification, management, and disposition of all primary nutrients produced on, imported to, and exported from the agricultural operation; Manure management conditions that protect water quality and improve manure utilization, and: Encompass all land where animals are kept and all land used for manure storage, treatment, or utilization that is under the control of the agricultural operator, Contain or manage manure to minimize the potential for nutrient loss or runoff before export to other agricultural operations or receiving facilities when agricultural operators have insufficient land to utilize manure and waste nutrients associated with animal production, and Minimize the potential for nutrient loss or runoff prior, during, and after application when an agricultural operator imports animal manure or waste nutrients associated with animal production for nutrient application on the operator's land. A nutrient management plan shall contain recommendations for an agricultural operation, as provided in COMAR 15.20.08.05B—I, for the management of fertilizer inputs and other nutrient sources. A recommendation shall be based on the best information available at the time a plan is prepared, as determined by the Department on a case-by-case basis. When implementing a plan, the operator may not exceed recommended nutrient application rates. The operator shall follow all other recommendations in the plan. Plan Adjustments. An operator may adjust the nutrient management recommendation in a plan for any of the following reasons: Occurrence of a condition beyond the control of the operator, including a natural disaster, unanticipated weather condition, animal mortality, or disease; or Occurrence of unanticipated conditions, such as market changes or economic factors that may cause modification of the agricultural operation, or other limitations, such as equipment calibration limits, or limits on the availability of commercial fertilizer blends to reasonably meet nutrient management recommendations. Any adjustment shall be: Consistent with plan criteria; and Documented under Regulation .06B of this chapter. An adjustment by the operator shall require that a revision to a nutrient management plan be made and documented when the adjustment is necessary because either new land or planting area, or animals, are not addressed in the current nutrient management plan and they exceed the thresholds described in §D of this regulation. Plan Maintenance, Updates, and Revisions. Except as provided in §D(2) of this regulation, at least once every 3 years from the date that the current plan was prepared, the operator shall revise and update the plan. An operator who uses only commercial fertilizer may use the current plan beyond the 3 years if all of the following conditions apply: The operator complies with the soil testing requirements set forth in COMAR 15.20.08.05D, including any changes to plan requirements under this chapter; The soil test analysis verifies that the phosphorus fertility index value (FIV) is 100 or less; and There have been no significant changes to the operation, including the crop rotation, management and tillage systems, and crop yield goals. Changes in an agricultural operation may require the operator to modify or update a plan when the information in the plan is inadequate, incomplete, or fails to address a change. These changes include a change: To the planned crop or cropping rotation, or introduction of a new crop when it is not currently addressed in an existing nutrient management plan, unless the new crop will have fertility management similar to that crop originally planned; Of nutrient source or soil test results that indicate a change in nutrient recommendations; Of 10 percent or greater in acreage managed, or 30 acres, whichever is less; or In the average annual number of animal units of 10 percent or greater, when the resultant manure production will require significant management adjustments. An operator shall maintain a plan to meet plan objectives, including implementation of best management practices, strategies, or a phased-in approach identified in the plan to achieve soil fertility within optimal ranges.