By Beth Germano

BOSTON (CBS) – The company facing criminal charges after two of its workers drowned in a flooded trench says the case should be dismissed.

Kevin Otto, the owner of Atlantic Drain Services, faces manslaughter charges.

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Kevin Otto going to court on Thursday. (WBZ-TV)

The company was digging a trench on Dartmouth Street in Boston Oct. 21, 2016 when it flooded and the walls collapsed as a fire hydrant ruptured killing 53-year-old Kevin Mattox and 47-year-old Robert Higgins.

“It’s very difficult to lose someone you love, it’s very difficult,” said a frustrated relative of Mattox leaving Suffolk Superior Courthouse.

Kevin Mattox. (WBZ-TV)

The defense says there are too many unanswered questions about the infrastructure the men were working in, including how the hydrant was maintained.

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“We don’t know anything about uncharted territory, how the pipe was supported, what caused water to spill, and what caused the break,” said defense attorney Veronica White.

Robert Higgins. (WBZ)

Family members were looking on wearing buttons in support of their loved ones as prosecutors insisted if the trench had been shored up properly to begin with the collapse would never have happened.

“If the trench had been properly excavated and shored these workers would not have come near this hydrant and would not have dug underneath it,” said prosecutor Lynn Feigenbaum.

The defense says the grand jury never heard from experts in the construction field, and as lay people didn’t have the expertise when considering the charges.  A judge has taken the request to drop the charges under advisement.

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Last year, the Occupational Safety and Health Administration cited Atlantic Drain Services following the deadly trench collapse in 2016.

Beth Germano