SA player signs with Australian Sevens
Van der Walt, a former member of the Brumbies extended playing squad, joins the program on an initial six-month contract.
Nick Poulos joins the Australian Sevens program as Head of Athletic Performance.
Tough forward Kennewell, from New South Wales, has signed a contract that ties him to the Sevens program for the next two years.
The 18-year-old product of Newington College impressed in the national youth Sevens championship in March.
He played an influential role in the Australian team that won silver at the 2015 Commonwealth Youth Games in Samoa earlier this month.
Nick Poulos joins the national Sevens program to replace Lachlan Penfold.
Poulos has previously worked for an array of sports and governing bodies both domestically and abroad, including stints in Japan and Qatar.
In a further boost to the program Lewis Holland has agreed a new two-year contract while James Stannard has penned a fresh 12-month deal.
The ARU also confirmed the departures of Michael Wells and Bradley Wilkin from the program.
Wells has opted to join the Brumbies, while Wilkin will join the NSW Waratahs from early October.
Ben Whitaker, General Manager – Pathways and Performance, Australian Rugby Union, said: "We are delighted to welcome Simon [Kennewell] and Stephan [van der Walt] into the program.
"Simon has excelled in both Sevens and Rugby Union through 2015.
"His decision to join the national Sevens program for the next two years is a healthy sign for the national program.
"Stephan's signing out of the Queensland and the national Sevens development program demonstrates an effective pathway into the national Sevens program for all aspiring players.
"Nick [Poulos], meanwhile, is highly-regarded in Australian sport and will bring tremendous experience and expertise to an important role within the Sevens program. His appointment is a coup for the Sevens set-up and the sport in generall," added Whitaker.
"Michael [Wells] and Brad [Wilkin] have been great contributors to the Sevens program and we are also proud that the program has played a significant part in their development as players.
"Their departure certainly creates opportunities for other members of the squad to come in and put their hand up for selection for future touring parties, including the 2015-16 World Rugby Sevens Series, 2016 Olympic Games and 2018 Commonwealth Games."
