ST. ALBANS, Vt. (AP) — The Vermont attorney general’s office sued the state’s largest dairy operation on Thursday, alleging the farm built a 90,000-square-foot barn addition and a 10-million gallon manure pit without the required permissions.

Attorney General T.J. Donovan said the expansion of the Lumbra Farm in Berkshire between 2016 and 2017 qualified as a large farm operation under state regulations, but it was done without the required permits and planning input from the Agency of Agriculture, Food and Markets and state environmental officials.

Donovan did not allege that the additions to the farm contributed to the water pollution woes that have plagued the state, but since the expansions were done without the needed permits, there was no way to determine if water qualify was affected.

Vermont has been struggling for years to improve water quality in Lake Champlain. Agricultural pollution from the northwestern corner of the state, which includes Berkshire, is considered to be one of the largest sources of that pollution.

The goal of the litigation is to have the farm, which is part of the Pleasant Valley Farms, which has operations throughout Franklin County, and is run by Mark St. Pierre and Amanda St. Pierre, get the needed permits under Vermont’s large farm regulations and pay a fee as determined by the court, Donovan said.

“I don’t think it’s mutually exclusive to have a robust agricultural economy, have strong farms — we all support that — and to be environmental stewards,” Donovan said Thursday outside the Franklin County courthouse after he filed the lawsuit. “There’s no point in having rules and regulations if they are not going to be followed and enforced.”

Claudine Safar, the attorney who is representing the farm in a related case, said Thursday she had not seen the lawsuit and so could not respond to it directly. But she thought it was premature for the state to file the suit because there is a separate legal case underway about which permit the St. Pierres needed for the barn: a medium farm permit, which the St. Pierres are seeking, or the large farm permit the state wants the farm to get. The St. Pierres were denied the medium farm permit but are appealing.

Safar said the appropriate permit is driven by the number of animals the barn will house, not its physical size. The barn on the Lumbra farm is designed to give birthing cows more room than a traditional barn, she said.

“This barn that they have was never designed to house the requisite numbers to fall under (a large farm permit),” Safar said.

Since the state became aware of the construction on the farm, the Agriculture Agency and the attorney general’s office has been in contact with the farm, but efforts to reach an agreement have been unsuccessful, said Assistant Attorney General Ryan Kane.