Coast Community College District officials said this week that the new planetarium at Orange Coast College in Costa Mesa is scheduled for completion by April, despite questions about the progress of construction.

During a district board meeting Wednesday, trustee Jim Moreno expressed concern about four letters between the district and Dana Point-based contractor MS Construction Management Group on why several completion dates hadn’t been met and about staffing at the construction site.

In an Aug. 7 letter, Jerry Marchbank, senior district director of facilities, planning and construction, said they hadn’t spent the amount of money on construction that they should have at that point, the “percentage of overall completion” was too low and he noted a lack of sufficient staff at the site.

Mike Saghafi, the project manager, stated in a letter Aug. 17 that the company had “continually been working toward timely completion of the [planetarium] without interruption.” He said crews had worked on Saturdays several times to “meet or beat” deadlines.

Marchbank assured trustees on Wednesday that the construction group is now on schedule and that he would continue to “stay on top of the contractors.”

Saghafi said in an interview Thursday that the project is on track and that the dome — the “most difficult part” — is complete.

“This project is a time-consuming task due to complications of the design, so it takes longer. But my main concentration is to make sure it’s done [correctly],” Saghafi said.

Trustees plan to tour the construction site in the near future.

Orange Coast College broke ground on the project in summer 2016, but talks of installing a modernized planetarium began years before trustees approved the college’s Vision 2020 facilities master plan in 2015. A planetarium built in the 1950s was torn down to make way for the new one.

Orange Coast officials have said the overall budget for the planetarium is about $20 million, with a majority of funding coming from a 2012 bond measure.

The college has received about $2.6 million in donations toward the project, including $1 million from a retired OCC professor.

The 12,000-square-foot structure will include a 129-seat auditorium and a Foucault pendulum that demonstrates Earth’s rotation. A “Science on a Sphere” exhibit will be showcased in the main lobby area.

The old planetarium could seat about 35 guests.

Priscella.Vega@latimes.com

Twitter: @vegapriscella