A state traffic engineer said yesterday she "probably" would recommend safety improvements at the Somerset Township intersection where five residents and staff members from a Washington County group care home were killed in a van-truck crash Thursday.

The improvements would be the first at Brownlee Road and Route 136 in about seven years. There have been 15 collisions at the Washington County site during the past five years.

Also yesterday, a spokeswoman for the state Department of Public Welfare, which oversees licensed personal care homes, said it would begin an investigation of the Mental Health Association of Washington County, which ran the "enhanced personal care home" where the five victims -- three of them residents -- lived or worked.

The investigation will include interviews with the home's staff and a review of its records.

State police said the 10 a.m. crash occurred when the northbound 2002 Chevrolet van driven by Sheryl Maiolini and carrying 10 passengers pulled into the path of a westbound tractor-trailer. Ms. Maiolini, 53, staffer Mary E. Watkins, 43, and residents John Maise, 61, Richard Paquet, 43, and Julia Hugus, 41, died in the crash.

The van was on a field trip to the Pittsburgh Zoo & PPG Aquarium. Seven people, including the truck driver, were injured in the crash. Four people, all residents of the personal care home, remained hospitalized. All were expected to be released soon.

Brownlee is a popular alternate route to and from Interstate 79 and Pittsburgh International Airport. At the accident site, it sits in a small valley while Route 136 intersects it at nearly right angles.

Route 136 traverses low hills on both sides of the intersection. Its traffic has a 45 mph speed limit, and the right of way, through the intersection.

PennDOT District 12 traffic engineer Rachel Duda, who visited the intersection yesterday, said that 10 of the previous 15 accidents at the intersection have involved eastbound Route 136 vehicles. She said northbound drivers on Brownlee -- the same direction the group home's van was traveling -- have the intersection's clearest view of opposing traffic.

Mrs. Duda said the last request from township supervisors for safety upgrades at the intersection was Jan. 29, 2001. Prior to that, she said there were requests for safety upgrades from private citizens and state Sen. J. Barry Stout, D-Bentleyville.

In response, PennDOT added stop signs on both sides of Brownlee in addition to curve and intersection warning signs on Route 136.

Mrs. Duda said she will likely recommend that placards be added to the intersection warning signs on Route 136 detailing the distance to the Brownlee intersection. She also is considering adding painted white "stop bars" beyond the Brownlee stop signs. The horizontal bars indicate drivers can safely pull forward beyond the stop signs, enabling better sight views of approaching Route 136 traffic.

Engineers will return to the site Monday, she said.

The tractor-trailer in the accident was operated by Stocker Trucking Co. of Gnadenhutten, Ohio. An administrator answering the phone at the company yesterday declined comment. U.S. Department of Transportation records show the company had a "satisfactory" safety rating as of Jan. 30.

Lynne Loresch, executive director of the Mental Health Association of Washington County, said she would wait for the victims' families to conduct private funerals before scheduling a memorial at the association.

"We're doing as well as can be expected," said Ms. Loresch, who has run the association for 23 years. "This is a family. Tragedies like this are always difficult."

She said there has been an outpouring of condolences from the community. Neighbors, she said, have brought by "food and warm thoughts." In addition, mental health professionals from throughout Washington County are providing counseling for residents and staff.