Webster Block LLC has been issued a $12,945 fine from the Massachusetts Department of Environmental Protection (MassDEP) for failing to report contaminants discovered during an environmental assessment it undertook at a Chelsea property in 2006.

The Chelsea property is the site of a 120-unit residential apartment complex being built by Webster Block, according to a statement. The site, located at 400 Eastern Ave., was purchased by the company on Dec. 29, 2006.

Webster Block notified MassDEP of elevated levels of petroleum and metals in late August, according to a statement. MassDEP then learned the company received a subsurface assessment of this contamination in soil as early as December 2006, but failed to file notification within 120 days as required.

"Having a report in hand, and knowing that elevated levels of contamination exist in soil and/or groundwater is considered essential information that must be shared and reported to MassDEP," said Richard Chalpin, director of MassDEP’s northeast regional office in Wilmington. "A great deal of damage, not to mention increased costs, are likely whenever contamination is ignored and allowed to spread out over time."

Webster Block will pay $8,000 of the fine; MassDEP will suspend the remaining $4,945 given the terms of the cleanup plan are met, according to a statement. A penalty provision has been put in place for any missed deadlines.