Four Connecticut companies have agreed to pay $613,000 to resolve legal matters for violating the state’s Clean Water Act. A fifth company is being served with state court action by the attorney general’s office.

The Connecticut Fund for the Environment announced last week that Electric Boat, Cytec, Whyco and Allegheny Ludlum will pay fines after receiving notices of intent to sue last September. The companies entered into formal Department of Environmental Protection consent orders to address the allegations in CFE’s notices.

Whyco, based in Thomaston, agreed to pay $300,000 in penalties and Allegheny Ludlum, which has a plant in Wallingford, agreed to pay $182,000 in penalties. Both plants were ordered to investigate and eliminate illegal discharges of toxins, heavy metals, solids, acid, oil and grease into rivers.

Cytec, also located in Wallingford, will pay $56,000 in penalties, while Electric Boat of Groton will pay $75,000. Both companies must institute spill control procedures.

Atlantic Wire of Branford refused to settle and now faces a lawsuit.

“The lawsuit sparked by our notice letter is in good hands” with Attorney General Richard Blumenthal, said Roger Reynolds, senior staff attorney with New Haven-based CFE, in a written statement. “We will work closely in court with him to ensure that Atlantic Wire ceases its illegal discharges, pays substantial penalties and mitigates the substantial damage it has done.”

Blumenthal has sued Atlantic Wire for 21 illegal discharges of toxic waste water into the Branford River since 2005. The most recent alleged incident came on Jan. 21, when Atlantic Wire reportedly discharged 7,500 gallons of acidic waste water.

“These actions mark a red letter day in Connecticut environmental enforcement history,” Blumenthal said in a written statement. “Polluters are on notice that Connecticut will vigorously enforce environmental laws to protect our rivers and streams from poisonous industrial waste.”

The lawsuit filed by Blumenthal seeks hundreds of thousands of dollars in fines. The attorney general has also asked the court for an immediate injunction prohibiting Atlantic Wire from discharging any waste water until it installs equipment to automatically halt outflows that exceed permitted levels. If granted, the injunction would force the company to collect and haul away discharge waters until the equipment is installed.

Last September, CFE sent formal notice against the five companies indicating its intention to bring citizen lawsuits for penalties and an injunction under the Clean Water Act. The act allows citizens to bring actions in cases where there are continuing violations.

The payments will fund a variety of environmental projects, some of which will directly benefit the affected rivers cited in the notice. CFE has agreed not to formally bring suit against the companies that entered into the consent orders.

By Douglas S. Malan