Cooke Aquaculture Pacific has been fined by the Washington Department of Ecology for repeatedly polluting the water at its net fish pen facility on the south end of Bainbridge Island.

Ecology officials said Wednesday the agency had issued the company an $8,000 penalty for violating state law that protects water quality.

Cooke has repeatedly cleaned dirty equipment on its Fort Ward dock on Rich Passage since last summer, state officials said.

Officials said the fine followed two warning letters, multiple phone calls to the company, and a notice of violation.

Cooke Aquaculture Pacific operates commercial Atlantic salmon net pens in multiple locations in Washington state waters, and Ecology investigated the company’s activities at its Bainbridge facility after receiving complaints from citizens that Cooke employees were pressure washing equipment on its Bainbridge dock and allowing the wastewater from the cleaning operation to flow into Puget Sound.

Ecology sent a warning letter to the company’s environmental permit coordinator in late August 2016, according to an administrative order issued Dec. 12 by the agency.

Another warning letter was sent on July 24 of this year for the same violations, and at least three Ecology officials warned Cooke via phone calls about the illegal activity.

Despite the warnings, Ecology said the company’s employees continued to use a pressure washer on equipment on the dock. A citizen sent in a video showing workers pressure washing a boat on the dock on Aug. 1, and more complaints — with photographs — were submitted to the state in mid September that showed employees working on a boat engine, as well as cleaning a boat, on the dock.

“We take our environmental obligations very seriously and have, in fact, modified our practices to address these matters,” said Nell Halse of Cooke Aquaculture. “We will be responding promptly and directly to the Department of Ecology.”

Cooke Aquaculture responded to the state’s earlier complaints in early October, eight days after a response was due, and said it had reminded employees not to pressure wash boat hulls on its Fort Ward dock.

The company also said no pressure washing of any kind was authorized on the dock at Fort Ward, and Cooke Aquaculture also promised to do any outboard engine maintenance on land away from the shoreline.

According to the administrative order issued Tuesday, the company has been immediately ordered to cease all pressure-washing activities on its Fort Ward dock, as well as scraping the bottom of boats, cleaning, and vehicle and equipment repairs on the dock.

Officials said Cooke Aquaculture was being penalized for:

• Unlawfully discharging polluting matter into state waters;

• Pressure washing equipment, nets, and vehicles over the water and allowing wastewater to enter Puget Sound;

• Changing boat engine oil over the water;

• Failing to put safeguards in place to protect water quality; and

• Failing to correct water quality violations when directed.

Cooke Aquaculture has 30 days to appeal the penalty.

Ecology officials said the penalty announced this week for Cooke Aquaculture’s Bainbridge operations was not related to the company’s net pen collapse at its facility near Cypress Island.

The state is continuing to investigate that incident, and Ecology may issue a separate enforcement action, officials said.