Section R18-9-403. Nitrogen Management General Permits: Concen- trated Animal Feeding Operations

A.      An owner or operator may discharge from a concentrated ani- mal feeding operation without submitting a notice to the Director, if the owner or operator complies with the following best management practices:

1.        Harvest, stockpile, and dispose of animal manure from a concentrated animal feeding operation to minimize dis- charge of any nitrogen pollutant by leaching and runoff;

2.        Control and dispose of nitrogen-contaminated water resulting from an activity associated with a concentrated animal feeding operation, up to a 25-year, 24-hour storm

event equivalent, to minimize the discharge of any nitro- gen pollutant;

3.        Following the requirements in subsection (B), construct and maintain a lining for an impoundment, used to con- tain process wastewater or contact stormwater from a concentrated animal feeding operation to minimize the discharge of any nitrogen pollutant; and

4.        Close a facility in a manner that will minimize the dis- charge of any nitrogen pollutant. If a liner was used in an impoundment:

a.         Remove liquids and any solid residue on the liner and dispose appropriately;

b.        Inspect any synthetic liner for evidence of holes, tears, or defective seams that could have leaked. If evidence of leakage is discovered:

i.         Remove the liner in the area of suspected leak- age,

ii.        Sample potentially impacted soil, and

iii.      Properly dispose of impacted soil or restore to background nitrogen levels;

c.         Cover the liner in place or remove it for disposal or reuse if the impoundment is an excavated impound- ment,

d.        Remove and dispose of the liner elsewhere if the impoundment is bermed;

e.         Grade the facility to prevent the impoundment of water; and

f.         Notify the Department within 60 days following clo- sure.

B.       Lining requirements for concentrated animal feeding operation impoundments.

1.        New impoundments. The owner or operator shall:

a.         Follow the NRCS guidelines for any newly con- structed impoundment or an impoundment first used after November 12, 2005, and

b.        Use a coefficient of permeability of 1 X 10-7 centi-

meters per second or less as acceptable liner perfor- mance. The owner or operator may include up to 1 order of magnitude reduction in permeability from manure sealing in impoundments that hold wastes having manure as a significant component.

2.        Impoundments already in use.

a.         The owner or operator shall maintain the existing seal for any impoundment first used before Novem- ber 12, 2005.

b.        If any of the following conditions exist at a concen- trated animal feeding operation, the Director shall send a notice requiring the owner or operator to reas- sess the performance of the lining system:

i.         The concentrated animal feeding operation is located within a Nitrogen Management Area designated under R18-9-A317; or

ii.        Existing conditions or trends in nitrogen load- ing to an aquifer will cause or contribute to an exceedance of an Aquifer Water Quality Stan- dard for a nitrogen pollutant at the point of compliance determined under A.R.S. § 49-244, based on the following information:

(1)     Existing contamination of groundwater by nitrogen species;

(2)     Existing and potential impact to ground- water by sources of nitrogen other than the concentrated animal feeding operation;

(3)     Characteristics of the soil surface, vadose zone, and aquifer;

(4)     Depth to groundwater;

(5)     The estimated operational life of the impoundment;

(6)     Location and characteristics of existing and potential drinking water supplies;

(7)     Construction material and design of exist- ing impoundment structure; and

(8)     Any other information relevant to deter- mining the severity of actual or potential nitrogen impact on the aquifer.

c.         The owner or operator shall, within 90 days of the Director’s notice, submit either:

i.         A report to the Department demonstrating con- sistency with NRCS guidelines and the accept- able liner performance criteria established in subsection (B)(1)(b); or

ii.        Plans and a schedule to upgrade the liner for the impoundment to meet the NRCS guidelines and the acceptable liner performance criteria in sub- section (B)(1)(b). The  Director  may provide additional time for the submittal of the plans and a schedule for upgrade, if the owner or operator demonstrates that technical or finan- cial assistance to develop the plans is needed.

d.        Preliminary decision.

i.         Within 90 days from the date of receipt, the Director shall review the report or the plans submitted under subsection (B)(2)(c) and pro- vide to the owner or operator a preliminary decision on the submittal.

ii.        The owner or operator may, within 30 days of the preliminary decision, submit written com- ments and supporting information to the Direc- tor on the preliminary decision.

iii.      The Director shall evaluate any comments on the preliminary decision and supporting infor- mation and, within 90 days of receipt of the comments and information, make a final deci- sion.

e.         Final decision.

i.         If the Director determines that the owner or operator has demonstrated that the lining sys- tem meets NRCS guidelines and the acceptable performance criteria in subsection (B)(1)(b), no additional action is necessary.

ii.        If the Director approves the plans and sched- ules under subsection (B)(2)(c)(ii), the owner or operator shall implement the plans within the time-frame specified in the approved schedule.

iii.      If the Director determines that the owner or operator failed to demonstrate that the lining system meets NRCS guidelines and the accept- able performance criteria in subsection (B)(1)(b) or that the schedule to upgrade the lining is not acceptable, the owner or operator shall upgrade the lining system within a time- frame specified by the Director.

iv.       The owner or operator may appeal the Direc- tor’s decision under A.R.S. Title 41, Chapter 6, Article 10.

3.        Notification requirement. The owner or operator of any lined impoundment shall either:

a.         Notify the Department of the type of liner that was used to line each impoundment by February 19 of each year following either:

i.         The first use of an impoundment not used before November 12, 2005; or

ii.        Completion of a liner upgrade required under this Section for an impoundment used before November 12, 2005; or

b.        Include the information required in subsections (B)(3)(a)(i) and (ii) in the next annual report submit- ted for the AZPDES Concentrated Animal Feeding Operation General Permit, issued under 18 A.A.C. 9, Article 9, Part C.

Historical Note

Adopted effective January 4, 1991 (Supp. 91-1). Section R18-9-403 renumbered from R18-9-203 and amended by final rulemaking at 7 A.A.R. 235, effective December 8,

2000 (Supp. 00-4). Amended by final rulemaking at 11

A.A.R. 4544, effective November 12, 2005 (05-3).