WAC 16-232-071   Application of pesticides in Walla Walla County -- Areas 2B, 4, and 6 -- Use restricted herbicides, aircraft boom length, pressure, and nozzle requirements.  The aerial application of restricted use herbicides in areas 2B, 4, and 6 shall be made in accordance with the following requirements:

     (1) The working boom length on fixed wing aircraft shall not exceed three-fourths of the wing span and the working boom length on a helicopter shall not exceed six-sevenths of the total rotor length where the rotor length exceeds forty feet.

     (2) Pressure for aerial equipment shall not exceed twenty-five psi at the nozzles.

     (3) Nozzles for aircraft:

     (a) Fixed wing:

     (i) Minimum nozzle orifice of .075 inches (no core plate): Provided, That RD8 nozzles with orifice size of 0.125 inches and No. 46 core plates may be used. Nozzles shall be directed downward and backward one hundred seventy degrees or more from the direction of flight.

     (ii) No flat fan nozzles shall be allowed.

     (b) Helicopter:

     (i) Minimum nozzle orifice of .063 inches (no core plate): Provided, That RD8 nozzles with orifice size of .125 inches and core plate No. 46 may be used. Nozzles shall be directed downward and backward ninety degrees or more from the direction of flight.

     (ii) No flat fan nozzles are allowed.



[Statutory Authority: Chapters 17.21, 15.58, and 34.05 RCW. 07-11-041A, § 16-232-071, filed 5/9/07, effective 6/9/07. Statutory Authority: Chapters 17.21 and 15.58 RCW. 00-24-002, § 16-232-071, filed 11/22/00, effective 12/23/00.]