459.305  Master matrix.
  1.  The department shall adopt rules for the development and use of a master matrix. The purpose of the master matrix is to provide a comprehensive assessment mechanism in order to produce a statistically verifiable basis for determining whether to approve or disapprove an application for the construction, including expansion, of a confinement feeding operation structure requiring a permit pursuant to section 459.303.
  a.  The master matrix shall be used to establish conditions for the construction of a confinement feeding operation structure and for the implementation of manure management practices, which conditions shall be included in the approval of the construction permit or the original manure management plan as applicable. The master matrix shall be used to determine all of the following:
  (1)  The appropriate location to construct a confinement feeding operation structure, including the proximity and orientation of a proposed confinement feeding operation structure to objects or locations for which separation distances are required pursuant to sections 459.202 or 459.204 and 459.310.
  (2)  The appropriate type of a confinement feeding operation structure required to be constructed, including the type and size of the manure storage structure, or the installation of a related pollution-control device.
  b.  The master matrix shall be designed to produce quantifiable results based on the scoring of objective criteria according to an established value scale. Each criterion shall be assigned points corresponding to the value scale. The master matrix shall consider risks and factors mitigating risks if the confinement feeding operation structure were constructed according to the application.
  c.  The master matrix may be a computer model. However, the master matrix must be a practical tool for use by persons when completing applications and by persons when scoring applications. To every extent feasible, the master matrix shall include criteria presented in the form of questions that may be readily scored according to ascertainable data and upon which reasonable persons familiar with the location of a proposed construction site would not ordinarily disagree.
  2.  The master matrix shall include criteria valuing environmental and community impacts for use by county boards of supervisors and the department. The master matrix shall include definite point selections for all criteria provided in the master matrix. The master matrix shall provide only for scoring of positive points and shall not provide for deduction of points. The master matrix shall provide for a minimum threshold score required to receive a satisfactory rating. The master matrix shall be structured to ensure that it feasibly provides for a satisfactory rating. Criteria valuing environmental impacts shall account for animal agriculture’s relationship to quality of the environment and the conservation of natural resources, and may include factors that refer to all of the following:
  a.  Topography.
  b.  Surface water drainage characteristics.
  c.  The suitability of the soils and the hydrology or hydrogeology of the site.
  d.  The proximity to public use areas and critical public areas.
  e.  The proximity to water sources, including high-quality water resources.
2002 Acts, ch 1137, §36, 68, 71
; 
2002 Acts, 2nd Ex, ch 1003, §259, 260, 262