Sharon Mayr said she was looking forward to "honoring the girls and making it a positive experience.
"I think it's going to be hard, being there, but at the same time I don't think it will be," she said. "It's going to be hard to realize that all those people are there for my daughter, but it's a good thing. It's hard to think when someone is gone — you worry that it's going to be like they were never there — but this way it's like, OK, she's still here."
Sharon Mayr said the two women will live on in another way: Proceeds from the memorial run will benefit the Elizabeth Nass Scholarship and the Rose Mayr Nursing Scholarship.
Both women, who had been active on the Mt. Hebron dance team, were preparing to go back to college as rising juniors before the accident. Mayr was studying nursing at the University of Delaware. Nass was studying early childhood education and headed back to James Madison University in Virginia.
Mayr's scholarship is sponsored by the Howard Hospital Foundation and is for any student pursing a degree in the nursing program at Howard Community College. Nass' is sponsored by the Mt. Hebron PTSA and is for any graduate planning on attending James Madison.
"In some way, it's like you can take what Rose would have achieved and try to inspire others," Sharon Mayr said.
Both mothers said they were grateful to the run's organizers and to the community.
"The response has been amazing, but I think I knew all along that it would be like this," Sue Nass said. "Both girls have a huge network of family and friends, all of whom I was sure would want to participate or be involved in some way. That said, the support and the response from the business community — many of whom did not know Rose and Elizabeth — has been more than we could have hoped for."
The memorial run organizers — Allwein, Warfel and Stevens, with the help of the two families — said that 554 people had signed up before online registration was cut off on Aug. 11. They hope to make it an annual event, but more than that, Warfel said, they want it to be a celebration.
"We want people to have good memories instead of the images people still carry of the derailment," he said.
Like Sharon Mayr, Sue Nass said it was "nice to have something positive to focus on" in planning the race.
"It is good for me to have contact with them in this way," she said. "It brings us together, and we laugh and talk about Elizabeth and Rose. I think it has been good for all of us."
For Sharon Mayr, growing closer with the Nass family "has been a help. I hope I can help them, too.
"The only positive thing that can possibly come of this is that you have someone else to look to," she said. "That's the only way I can describe it."
The race will begin at 8:30 a.m. at the Howard County Circuit Courthouse and end at Parking Lot F at the intersection of Ellicott Mills Drive and Frederick Road. Following the race, there will be music, food and drinks in the parking lot.
Some business owners are running. Linda Miller, owner of St. John's Jewelers on Route 40, said nearly her entire staff will be in the race. Some of those employees are Mt. Hebron students and graduates.
Meg Ross, an employee at the store and a rising senior and member of the Mt. Hebron volleyball team, said many students are planning to participate.
"It's more than a show of school spirit; it's a show of community spirit," said Ross. "The race is going to be so positive, and everyone is really excited for it. It'll be a good atmosphere."
The event organizers are encouraged by the momentum the event has generated, but Carney said, "That's just Ellicott City.
"This is such a close-knit community down here," he said. "We have the best people in the world who come down to the Historic District.
"I'm not surprised at all by the interest. It's exactly what I would expect, and it's a good thing. It's a sad tragedy, but it's brought a lot of people together."
Coming together in trying times is "just in the fiber of this town," said County Council member Courtney Watson, who represents Ellicott City.
"It is resilient," she said. "Ellicott City has been here long before us, and it will be here long after us. Ellicott City might stumble, but it always gets back up, and the community members are all a part of it.
"The town was in such agony that week, it was surreal. It was so sad. (The race) will be a very strong message to the parents and families of Rose and Elizabeth that they are supported and the girls will be remembered always."