R.M. Packer Co. of Vineyard Haven, the Vineyard’s major oil supplier, has agreed to pay a $78,000 fine for violating the federal Clean Water Act and Oil Pollution Prevention rules.

According to a release from the federal Environmental Protection Agency on Wednesday, the Packer company failed to adequately implement a spill prevention, control and countermeasure plan. The EPA also said the company did not sufficiently maintain proper containment for its tanks and loading rack.

Because the Packer facility is next to Vineyard Haven harbor, the agency said the violations presented a significant threat of an oil spill into navigable water.

Yesterday, Ralph M. Packer Jr., who owns the company, sent the Gazette a two-page letter responding to the EPA release.

“The EPA has felt that the Packer Company threatens the navigable waters of Vineyard Sound,” Mr. Packer wrote. “The terminal has been in continuous operation for almost 80 years and has no release in the navigable waters of Vineyard Sound. It has not had a fire or serious injuries.”

Following an EPA inspection in 2000, the company submitted a schedule for coming into compliance, including upgrading its tanks and containment areas. When Packer fell behind schedule, the EPA sent a letter to the company notifying the company that its oil tanks on Beach Road were still out of compliance.

The EPA subsequently issued an administrative order to R.M. Packer Co. requiring the company to comply with the storage tank requirements.

Following continued delays, the agency initiated the current action against the company.

In his letter, Mr. Packer said the company engaged a professional environmental engineering firm to develop a plan for the Vineyard Haven terminal.

“The plan was submitted and rejected due to the time frame to accomplish the improvements and due to the fact that it was not prepared by a professional engineer as required,” he wrote, adding that the company faced simultaneous requirements to develop terrorism security plans for its Vineyard Haven and New Bedford terminals.

According to the EPA, spill prevention and control laws help ensure that a tank failure or spill does not lead to oil being released into drinking water wells, rivers or streams.

Packer has agreed to upgrade its facility and comply with the spill prevention regulations, according to the EPA. The company has poured concrete in the previously unpaved tank containment area, upgraded containment for other, smaller tanks and installed high-level alarms and corrosion protection for the active tanks. In addition, Packer is working with an engineer to update its spill prevention plan.

“We have fulfilled all the tank inspections,” Mr. Packer wrote. “Tanks that were not in use have been taken out of service.”

Packer has been cited before for environmental violations on the Vineyard.

In September 2007, the company agreed to address a list of fire safety violations at the Edgartown Marine harbor fuel dock raised by the state Department of Fire Services. The violations ranged from an invalid permit to inoperable emergency fuel shutoff valves.

In 2002, following an investigation by the EPA into the release of harmful pollutants into the air, Packer agreed to spend $300,000 in emissions control equipment at its Vineyard Haven terminal and to pay a penalty of $200,000.

Also in 2002, the company admitted failing to report two oil spills during the summer of 2001. One was in Lagoon Pond, the other in Edgartown Harbor.

In 1998, a Massachusetts appeals court held Packer responsible for $1.3 million in damages and interest at a fuel tank spill at a gasoline station in Oak Bluffs.

In his letter yesterday Mr. Packer wrote: “Heating oil is a necessity of life and on the other hand if treated improperly is a threat to our fragile environment. What we find extremely devastating is that the federal government considers our family-owned business threatening in any way to our local waters. We, as a family, have lived for 350 years on the Vineyard shore. We hold dear our Island and our community.”