Requires the department of ecology to: (1) Authorize the use of imidacloprid to control infestations of burrowing shrimp in Willapa Bay and Grays Harbor for the 2019 treatment season;

(2) Issue a national pollutant discharge elimination system permit for the use of pesticides to control infestations of burrowing shrimp in association with the cultivation of shellfish; and

(3) Delegate certain authorities, regarding the regulation of pesticides used to control burrowing shrimp on tidelands, to the department of agriculture through a memorandum of understanding.

Transfers powers, duties, and functions of the department of ecology, pertaining to chapter 90.48 RCW as it relates to the regulation of the pesticides, to the department of agriculture.

Exempts the following from the requirements of the state environmental policy act: The issuance of a national pollutant discharge elimination system permit or waste discharge permit for the use of the pesticides.

Makes appropriations from the state general fund to the department of ecology for conducting a study on the use of imidacloprid for control of burrowing shrimp in Willapa Bay and Grays Harbor; and from the state toxics control account to the department of agriculture for studying the impacts of the use of imidacloprid as a means to control burrowing shrimp.