While Ilya and Yan Girlya were planning Diggerland USA, the "construction-themed adventure park" they are building in Berlin Township, the brothers consulted experts, including a trio named Aiden, Dylan, and Bianca.

Ilya's two boys, 8 and 4, and Yan's daughter, 7, reached pretty much the same conclusion as conventional focus groups: The $8 million, 14-acre, action-packed attraction is a child's dream come true.

After all, few kids of any age would pass up a chance to ride, drive, or operate a life-size Tonka toy - like the ones that gave me so many happy hours in the 1960s.

"We want Diggerland USA to be a place where families can do something together that they can't do anywhere else," says Ilya, 38, welcoming me into the colossal construction site on Cooper Road at Pinedge Drive. Work started in November and is about 85 percent complete.

Says Yan, 41: "We want to provide wholesome family entertainment. Everybody was a kid once, playing with trucks, making tunnels in the sand at the Shore."

The brothers, who emigrated with their parents from the Soviet Union in the late 1970s, grew up in Cherry Hill and now live in Mount Laurel. Their family owns the Sambe Construction Co. Inc. in Pennsauken, and they built and operate Sahara Sam's Water Park in Berlin Township.

They started brainstorming Diggerland USA in 2010, ultimately modeling the concept on the four Diggerland UK parks in Britain. The Berlin Township park is being promoted as the first of its kind in America and is expected to open in June.

The Spin Dizzy

"People are really excited," says Sharon Rushen, social-media and marketing manager for Diggerland USA. "They love it when we post pictures of the equipment as it comes in on our Facebook page."

Some of the modified construction vehicles manufactured by the British firm JCB (which serves the British parks as well) are awaiting clearance by U.S. Customs at the Port of New York and New Jersey.

"The Spin Dizzy will be here," says marketing director Chris Peters, pointing to a prominent spot where a 50,000-pound excavator will rotate while raising aloft a bucket customized to seat nine.

Elsewhere in the park, a 50-piece fleet of diggers, backhoes, tractors, telescopic handlers, "skidsteer" loaders, and two turbo-diesel military transport trucks will offer rides or hands-on thrills.

The Spin Dizzy and transport trucks will be operated by park staff. Many of the other pieces have been modified by the manufacturer to enable operation by adults and older children at limited speeds on marked courses.

Staying safe

Even young children will be able to operate some of the equipment while sitting on the laps of parents or guardians.

"It's not a rodeo. You can't just jump on a machine and go crazy," Ilya says. "We don't just put a 5-year-old on a piece of 20-ton equipment and hope nothing happens."

Explaining the unusual amusement park to officials of the state Department of Community Affairs turned out to be the biggest challenge, the brothers say.

"We did have a lot of work to try and understand how they fit into the regulations, and how we could make sure they would be safely operating," says Michael Triplett, supervisor of enforcement of the carnival and amusement ride safety unit.

Diggerland USA has "met all of the requirements they need to operate the rides," Triplett adds. "They need to meet our regulations and follow the . . . standards, and they have done that. Their permits are printed, and they just need [final] inspection once the rides are installed, and they're ready."

"When they came to the planning board, the [township's] chief concern was safety," Mayor Phyllis Magazzu says. "I am confident it will be safe."

The mayor, a mother of seven, can't wait for Diggerland USA to open. It will create 50 jobs and help "put Berlin Township on the map," she says, adding that the park "is really cool."

Despite my Tonka nostalgia, I can't imagine my grown-up self at the controls of, say, an excavator.

But Diggerland USA also will host performances by the Dancing Diggers, a troupe that "dances and does tricks and acrobatics in backhoes," Peters says.

"It's all choreographed to music."

Music? Dancing? A Broadway-style revue, starring backhoes?

Now that's cool.