Ariz. Admin. Code § R18-2-610 - Definitions for R18-2-610.01, R18-2-610.02, and R18-2-610.03

The definitions in R18-2-101 and the following definitions apply to R18-2-610.01, R18-2-610.02, and R18-2-610.03:

1. "Access restriction" means reducing PM emissions by reducing the number of trips driven on agricultural aprons and access roads by restricting or eliminating public access to noncropland or commercial farm roads with signs or physical obstruction at locations that effectively control access to the area.

2. "Aggregate cover" means reducing PM emissions and wind erosion and stabilizing soil by applying and maintaining gravel, concrete, recycled road base, caliche, or other similar material to noncropland or commercial farm roads. The aggregate should be clean, hard and durable, and should be applied and maintained to a depth sufficient to reduce PM emissions.

3. "Area A" means the area delineated according to A.R.S. § 49-541(1).

4. "Best management practice" (BMP) means a technique verified by scientific research, that on a case-by-case basis is practical, economically feasible, and effective in reducing PM emissions from a regulated agricultural activity.

5. "Cessation of Night Tilling" means the discontinuation of tillage from sunset to sunrise on a day identified by the Maricopa or Pinal County Dust Control Forecast as being high risk of dust generation.

6. "Chemical irrigation" means reducing a minimum of one ground operation across a commercial farm by applying a fertilizer, pesticide, or other agricultural chemical to cropland through an irrigation system, which reduces soil disturbance and increases efficiency of application.

7. "Chips/ mulches" means reducing PM emissions and soil movement and preserving soil moisture by applying and maintaining nontoxic chemical or organic dust suppressants to a depth sufficient to reduce PM emissions. Materials shall meet all specifications required by federal, state, or local water agencies, and is not prohibited for use by any applicable regulations.

8. "Combining tractor operations" means reducing soil compaction and a minimum of one tillage or ground operation across a commercial farm by using a tractor, implement, harvester, or other farming support vehicle to perform two or more tillage, cultivation, planting, or harvesting operations at the same time. If Equipment modification is also chosen as a BMP, and uses the same practices as described in this BMP, this action is considered one BMP.

9. "Commercial farm" means 10 or more contiguous acres of land used for agricultural purposes within the boundary of the Maricopa PM nonattainment area and Maricopa County portion of Area A, a PM nonattainment area designated after June 1, 2009 as stated in A.R.S. § 49-457(O)(1)(f), or the Pinal County PM Nonattainment Area.

10. "Commercial farm road" means a road that is unpaved, owned by a commercial farmer, and is used exclusively to service a commercial farm.

11. "Commercial farmer" means an individual, entity, or joint operation in general control of a commercial farm.

12. "Committee" means the Governor's Agricultural Best Management Practices Committee as established by A.R.S. § 49-457.

13. "Conservation Tillage" means a tillage system that reduces a minimum of three tillage operations. This system reduces soil and water loss by planting into existing plant stubble on the field after harvest as well as managing the stubble so that it remains intact during the planting season.

14. "Cover crop" means establishing cover crops that maintain a minimum of 60 percent ground cover. Native or volunteer vegetation that meets the minimum ground cover requirement is acceptable. Compliance shall be determined by the Line Transect Test Method, NRCS National Agronomy Manual, Subpart 503.51, Estimating Crop Residue Cover, amended through February 2011 (and no future editions).

15. "Critical area planting" means reducing PM₁₀ emissions and wind erosion by planting trees, shrubs, vines, grasses, or other vegetative cover on noncropland in order to maintain at least 60 percent ground cover. Compliance shall be determined by the Line Transect Test Method, NRCS National Agronomy Manual, Subpart 503.51, Estimating Crop Residue Cover, amended through February 2011 (and no future editions).

16. "Cropland" means land on a commercial farm that:

a. Is within the time-frame of final harvest to plant emergence, but does not include tillage activities;

b. Has been tilled in a prior year and is suitable for crop production, but is currently fallow; or

c. Is a turn-row.

17. "Cross-wind ridges" means stabilizing soil and reducing PM emissions and wind erosion by creating soil ridges in a commercial farm by tillage or planting operations. Ridges should be at least four inches in height, and be aligned as perpendicular as possible to the prevailing wind direction.

18. "Dust Control Forecast" means a forecast, which shall identify a low, moderate or high risk of dust generation for the next five consecutive days and shall be issued by noon on each day the forecast is generated. When developing these forecasts, the department shall consider all of the following:

a. Projected meteorological conditions, including:

i. Wind speed and direction,

ii. Stagnation,

iii. Recent precipitation, and

iv. Potential for precipitation;

b. Existing concentrations of air pollution at the time of the forecast; and

c. Historic air pollution concentrations that have been observed during meteorological conditions similar to those that are predicted to occur in the forecast.

19. "Equipment modification" means reducing PM emissions and soil erosion during tillage or ground operations by modifying and maintaining an existing piece of agricultural equipment, installing shielding equipment, modifying land planting and land leveling, matching the equipment to row spacing, or grafting to new varieties or technological improvements. If combining tractor operations is also chosen as a BMP, and uses the same practices as described in this BMP, this action is considered one BMP.

20. "Fallow Field" means an area of land that is routinely cultivated, planted and harvested and is unplanted for one or more growing seasons or planting cycles, but is intended to be placed back in agricultural production.

21. "Field Capacity" means the amount of water remaining in the soil two days after having been saturated and after free drainage has ceased.

22. "Forage Crop" means a product grown for consumption by any domestic animal.

23. "Genetically Modified" (GMO) means a living organism whose genetic material has been altered, changing one or more of its characteristics.

24. "GPS: Global Position Satellite System" means using a satellite navigation system on farm equipment to calculate position in the field.

25. "Green chop" means reducing soil compaction, soil disturbance and a minimum of one ground operation across a commercial farm by harvesting a Forage Crop without allowing it to dry in the field.

26. "Ground operation" means an agricultural operation that is not a tillage operation, which involves equipment passing across the field. A ground operation includes harvest activities. A pass through the field may be a subset of a ground operation.

27. "Harvest" means the time after planting up through harvest, including gathering mature crops from a commercial farm, as well as all actions taken immediately after crop removal, such as cooling, sorting, cleaning, and packing.

28. "Integrated Pest Management" means reducing soil compaction and a minimum of one ground operation across a commercial farm for spraying by using a combination of techniques including organic, conventional, and biological farming practices to suppress pest problems.

29. "Limited harvest activity" means performing no ground operations on a day identified by the Maricopa or Pinal County Dust Control Forecast to be high risk for dust generation.

30. "Limited tillage activity" means performing no tillage operations on a day identified by the Maricopa or Pinal County Dust Control Forecast to be high risk for dust generation.

31. "Maricopa PM nonattainment area" means the Phoenix planning area as defined in 40 CFR 81.303, which is incorporated by reference in R18-2-210.

32. "Multi-year crop" means reducing PM emissions from wind erosion and a minimum of one tillage and ground operation across a commercial farm, by protecting the soil surface by growing a crop, pasture, or orchard that is grown, or will be grown, on a continuous basis for more than one year.

33. "Noncropland" means any commercial farm land that:

a. Is no longer used for agricultural production;

b. Is no longer suitable for production of crops;

c. Is subject to a restrictive easement or contract that prohibits use for the production of crops; or

d. Includes a ditch, or ditch bank, equipment yard, storage yard, or well head.

34. "NRCS" means the Natural Resource Conservation Service.

35. "Organic material cover" means reducing PM emissions and wind erosion and preserving soil moisture by applying and maintaining cover material such as animal waste or plant residue, to a soil surface to reduce soil movement. Material shall be evenly applied and maintained to a depth sufficient to reduce PM emissions and coverage should be a minimum of 70 percent.

36. "Permanent cover" means reducing PM emissions and wind erosion by maintaining a long-term perennial vegetative cover on cropland that is temporarily not producing a major crop. Perennial species such as grasses and/or legumes shall be used to establish at least 60 percent cover. Compliance shall be determined by the Line Transect Test Method, NRCS National Agronomy Manual, Subpart 503.51, Estimating Crop Residue Cover, amended through February 2011 (and no future editions).

37. "Pinal County PM Nonattainment Area" means the West Pinal PM₁₀ planning area and the West Central PM_2.5 planning area, as defined in 40 CFR 81.303, and incorporated by reference in R18-2-210.

38. "Plant stubble" means stubble on the soil surface, which insulates soil to reduce evaporation of moisture, and also protects the soil from wind and water erosion.

39. "Planting based on soil moisture" means reducing PM emissions and wind erosion by applying water or having enough moisture in the soil to germinate the seed prior to planting. Soil must have a minimum soil moisture content of 60% of field capacity at planting depth. Compliance shall be determined by NRCS Estimating Soil Moisture by Feel and Appearance Method, amended through April 1998 (and no future editions).

40. "PM" includes both particulate matter with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers as measured by a reference method based on 40 CFR 50 Appendix L, or by an equivalent method designated according to 40 CFR 53 ; and particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers as measured by a reference method contained within 40 CFR 50 Appendix J or by an equivalent method designated in accordance with 40 CFR 53, as incorporated by reference in Appendix 2.

41. "Precision Farming" means reducing the number of passes across a commercial farm by at least 12 inches per pass by using GPS to precisely guide farm equipment in the field.

42. "Reduce vehicle speed" means reducing PM emissions and soil erosion from the operation of farm vehicles or farm equipment on noncropland or commercial farm roads at speeds not to exceed 15 miles per hour. This can be achieved through installation of engine speed governors, signage, or speed control devices.

43. "Reduced harvest activity" means reducing soil disturbance, soil and water loss, and the number of mechanical harvest passes by a minimum of one ground operation across a commercial farm, by means other than equipment modification or combining tractor operations.

44. "Reduced tillage system" means reducing soil disturbance, soil and water loss, by using a single piece of equipment that reduces a minimum of three tillage operations, by means other than equipment modification or combining tractor operations.

45. "Regulated agricultural activity" means a regulated agricultural activity as defined in A.R.S. § 49-457(O)(1)(a) through (O)(1)(d).

46. "Regulated area" means the regulated area as defined in A.R.S. § 49-457(O)(6).

47. "Residue management" means reducing PM emissions and wind erosion by maintaining a minimum of 60 percent ground cover of crop and other plant residues on a soil surface between the time of harvest of one crop and the commencement of tillage for a new crop. Compliance shall be determined by the Line Transect Test Method, NRCS National Agronomy Manual, Subpart 503.51, Estimating Crop Residue Cover, amended through February 2011 (and no future editions).

48. "Sequential cropping" means reducing PM emissions and wind erosion by growing crops in a sequence or close rotation that limits the amount of time bare soil is exposed on a commercial farm to 30 days or less.

49. "Shuttle System/Larger Carrier" means reducing one out of every four trips across a commercial farm by using multiple or larger bins/trailers to haul commodity from the field.

50. "Significant Agricultural Earth Moving Activities" means either leveling activities conducted on a commercial farm that disturb the soil more than 4 inches below the surface, or the creation, maintenance and relocation of: ditches, canals, ponds, irrigation lines, tailwater recovery systems (agricultural sumps) and other water conveyances, not to include activities performed on cropland for tillage, ground operations or harvest.

51. "Silt content test method" means the test method as described in Appendix 2.

52. "Stabilization of soil prior to plant emergence" means reducing PM emissions by applying water to soil prior to crop emergence in order to cause the soil to form a visible crust.

53. "Surface roughening" means reducing PM emissions or wind erosion by manipulating a soil surface by means such as rough discing or tillage in order to produce or maintain clods on the land surface. Compliance shall be determined by NRCS Practice Code 609, Surface Roughening, amended through November 2008 (and no future editions).

54. "Synthetic particulate suppressant" means reducing PM emissions and wind erosion by providing a stabilized soil surface on noncropland or commercial farm roads with a manufactured product such as lignosulfate, calcium chloride, magnesium chloride, an emulsion of a petroleum product, an enzyme product, or polyacrylamide that is used to control particulate matter.

55. "Tillage" means any mechanical practice that physically disturbs the soil, and includes preparation for planting, such as plowing, ripping, or discing.

56. "Tillage based on soil moisture" means reducing PM emissions by irrigating fields to the depth of the proposed cut prior to soil disturbances or conducting tillage to coincide with precipitation. Soil must have a minimum soil moisture content of 40-60% of field capacity at planting depth. Compliance shall be determined by NRCS Estimating Soil Moisture by Feel and Appearance Method, amended through April 1998 (and no future editions).

57. "Timing of a tillage operation" means reducing wind erosion and PM emissions by performing tillage operations that minimize the amount of time within 45 days.

58. "Tillage operation" means an agricultural operation that mechanically manipulates the soil for the enhancement of crop production. Examples include discing or bedding. A pass through the field may be a subset of a tillage operation.

59. "Track-out control system" means minimizing any and all material that adheres to and agglomerates on all vehicles and equipment from noncropland or commercial farm roads or and falls onto paved public roads or shoulders to paved public roads by using a device or system to remove mud or soil from a vehicle or equipment before the vehicle enters a paved public road. Devices such as a grizzly, a gravel pad or a wheel wash system can be used.

60. "Transgenic Crops" means reducing a minimum of one tillage or ground operation, the number of chemical spray applications, or soil disturbances by using plants that are genetically modified.

61. "Transplanting" means reducing a minimum of one ground operation across a commercial farm and minimizing soil disturbance by utilizing plants already in a growth state as compared to seeding.

62. "Unpaved vehicle or equipment traffic area" means any area of noncropland that is used for the fueling, servicing, receiving, transfer, parking or storing of equipment or vehicles.

62 63. "VDT" (Vehicle trips per day) means trips per day made by one vehicle, in one direction.

63 64. "Watering" means reducing PM emissions and wind erosion by applying water to noncropland or commercial farm road bare soil surfaces during periods of high traffic until the surfaces are visibly moist.

64 65. "Watering on a high risk day" means reducing PM emissions and wind erosion by applying water to commercial farm road bare soil surfaces until the surfaces are visibly moist, on a day forecast to be high risk for dust generation by the Maricopa or Pinal County Dust Control Forecast.

65 66. "Wind barrier" means reducing PM emissions and wind erosion by constructing a fence or structure, or providing a woody vegetative barrier by planting a row of trees or shrubs, perpendicular or across the prevailing wind direction to reduce wind speed by changing the pattern of air flow over the land surface. For fences and structures, the wind barrier shall have a density of no less than 50% and the height of the wind barrier must be proportionate to the downwind protected area. The downwind protected area is considered ten times the height of the wind barrier. For vegetative barriers, compliance shall be determined by NRCS Conservation Practice Standard, Code 380, Windbreak/Shelterbelt Establishment, amended through August 21, 2009 (and no future editions).

Notes

Ariz. Admin. Code § R18-2-610

Former Section R18-2-610 renumbered to R18-2-612; new Section R18-2-610 adopted by final rulemaking at 6 A.A.R. 2009, effective May 12, 2000 (Supp. 00-2). Amended by exempt rulemaking at 13 A.A.R. 4326, effective November 14, 2007 (Supp. 07-4). Amended by exempt rulemaking at 18 A.A.R. 137, effective December 29, 2011 (Supp. 11-4). Subsection (A) corrected at the request of the Department, Office File No. M12-133, filed April 5, 2012 (Supp. 11-4). Amended by exempt rulemaking at 30 A.A.R. 1156, effective 7/2/2015. Amended by final exempt rulemaking at 27 A.A.R. 2747, effective 11/3/2021.