On Monday, June 13, Atherton became the first community on the Caltrain corridor to have a "quiet zone" where train operators can only blow their horns when they encounter a hazard, but an observer says Caltrain isn't honoring it much of the time.

Nerissa Dexter, the member of Atherton's Rail Committee who did the research leading to the establishment of the quiet zone, spent much of Monday sitting near the train tracks at the Fair Oaks rail crossing in Atherton tracking whether or not train operators paid attention to the new regulations.

She said compliance was at 81 percent Monday morning but has since dropped to only 60 percent.

The quiet zone does not include the entire town of Atherton, but just the area around the Fair Oaks Lane rail crossing. The Watkins Avenue crossing is not part of the quiet zone because it does not have the type of safety equipment the federal government requires for a quiet zone, but the town is investigating making changes so the zone can be expanded.

In the morning of the first day with the quiet zone, Ms. Dexter says, the train operators did not sound their horns approaching the crossing 81 percent of the time. "The quiet zone has taken effect and it has really minimized the noise pollution," she said early Monday afternoon.

The change was apparent to nearby residents, Ms. Dexter said. Members of a family who live between the railroad tracks and Middlefield Road stopped by to thank her for her work on the quiet zone. "They were thrilled," she said. "They usually get woken up at 6:30 in the morning," but on Monday, they were not.

"It was really exciting to see somebody that happy," said Ms. Dexter, speaking on her cellphone from her observation post near the Atherton train station. As she spoke, however, a train horn blared in the background.

"So for we've had a minimum of a 19 percent violation rate," she said. "Our goal is to work with Caltrain to get 100 percent compliance," she said. "That's what we're all looking for."

Caltrain spokeswoman Tasha Bartholomew said Caltrain will observe the quiet zone and is happy to work with the town. "We definitely want to be in compliance," she said.

Town officials had warned that train horns would still sound quite near to the Fair Oaks crossing because the Watkins crossing is so close. But Ms. Dexter said that the two crossings are 0.3 miles apart and train horns are not to sound any more than 0.25 miles from a crossing.

She said violations of the quiet zone or other regulations about when, where and how a train horn can sound can result in a fine of $1,000 for an accidental violation or $2,000 for a "willful" violation.

The town may have a bit of work ahead with Caltrain. Ms. Dexter said that on Monday afternoon, nearly 34 percent of train operators violated the quiet zone.

She said that between 6:55 a.m. and noon she "carefully observed" 32 trains, with 6 violating the quiet zone. Between 3:15 and 7:45 p.m., she observed 35 trains with 12 violations.

On Tuesday morning, Ms. Dexter was back at her post listening for train horns. Between 7:10 a.m. and 11:15 a.m., 40 percent of the 30 trains that passed by sounded their horns in the quiet zone, she said.

Ms. Dexter explained exactly how she is observing compliance with the quiet zone.

For northbound trains heading in the San Francisco direction, she makes the observation visually. "There should be no train blast after the train leaves the Watkins crossing," she said." "At Fair Oaks, you can see the Watkins crossing gates clearly. I can see exactly where the train leaves the Watkins crossing."

As for southbound trains, the fact that the nearest crossing is at Chestnut Street in Redwood City, makes those observations easy, she said. "There should be no train horn blasts before or through the Fair Oaks Crossing. They should only be starting to sound in advance of Watkins," she said. Ms. Dexter looked on GoogleEarth to figure out the .25 mile distance from Watkins and can see the spot on the tracks where train horn blasts can restart, she said.

Ms. Dexter said she logs the locomotive number, time and direction of each train she observes and then notes what happened with each train.

"My goal here is to be completely accurate," she said.

Atherton City Manager George Rodericks said Atherton will observe Caltrain's quiet zone compliance this week, and share those observations with Caltrain.

Mr. Rodericks said Caltrain had requested the town delay the quiet zone implementation so train operators could be trained. Instead, he said, the town promised it will not file any formal non-compliance complaints with the Federal Rail Administration without allow Caltrain to work with train operators to solve any problems first.