A company contracted by the Palo Alto school district sprayed herbicides too many times at local schools last year, according to a county investigation that concluded in July.
The overspraying violated state law but did not constitute a health hazard to students, the county found.
A combination of chemicals, including Diuron 80, was sprayed three times at high schools and middle schools -- a violation of the recommended maximum of two Diuron 80 applications per year, according to the county report.
The investigation, conducted by the Department of Agriculture, found the overspraying did not constitute a health hazard because the total amount of Diuron sprayed, 12 pounds, was below the 15 pounds determined to be hazardous. Diuron kills living plants and inhibits new growth.
Evans West Valley Spray, contracted to do the work, violated state law requiring pesticides to be applied in accordance with label instructions, which for Diuron specify two sprayings per year.
In addition, the school district violated California's Healthy Schools Act by failing to notify schools and students about which chemicals were being sprayed and when.
Evans West Valley Spray applied the herbicide mixture at Gunn and Palo Alto high schools and JLS, Terman and Jordan middle schools in February, December and August of 2006 when school was not in session. According to a document the company provided to county investigators, the spraying covered athletic fields, outdoor landscape and "hardscape," including parking lots and sidewalks.
Elementary schools were also sprayed between one and two times and only on areas designated outdoor landscape.
The spray mixture contained Roundup, an herbicide for growing plants, Diuron, which kills plants before they sprout, and No Foam B, which helps herbicides stick to plants.
The school district is adopting policies to better align with the Healthy Schools Act, Maintenance, Operations and Construction Manager Pete Pearne said.
Students will be notified several days in advance about sprayings this year, Pearne said.
"If they (parents) feel that Johnny has got some kind of asthma or something like this, (the advance notice) might be effective because they might want to keep him home," Pearne said. Most spraying occurs when students are not in school, he added.
Because the county found no health hazard, the district does not plan to take extra safety precautions regarding the sprayed areas, Pearne said. Diuron is on a Healthy Schools Act list of acceptable chemicals, he added.
However, the district is canceling its ongoing spraying contracts and switching to an as-needed basis this year, Pearne said.
"In other words, there's no more blanket contract where they spray every three or six months. We'll call them when we need them," Pearne said.
The district will also post notification of herbicide applications, rather than rely on companies, Pearne said.
"We're taking a responsibility for posting so that we know it's done," Pearne said.
Posting is one of four requirements of California's Healthy Schools Act. The others mandate recording what is used and where, and notifying parents and schools. Aside from the notification violation, the district has been following the act's requirements, Pearne said.
"We have been pretty much compliant with the Healthy Schools Act," he said.
The district is also following the act's recommendation that districts create an Integrated Pest Management plan to regulate pesticide use, Pearne said. All maintenance managers will attend a state-sponsored workshop about plan drafting on Oct. 26, he said.
Workshop attendance is part of pre-existing compliance efforts, Pearne said -- he did not know about the overspraying until the county investigation concluded.
"I really wasn't aware of it until this report came out. We were relying on our pesticide companies to take care of that sort of thing," he said.
The overspraying resulted from a calendar error, said Mike Evans, owner of Evans West Valley Spray. The last December application was just within the time frame that would have marked an entire year since the initial application of the three, he said.
"It was kind of a technical thing that we blew by doing it in that time frame. It's a lot of details and sometimes you can miss something," he said. He added that the amount sprayed was not unhealthy and said the public could trust his company to perform safe work.
"I've been dispersing pesticides in the public since I was 19 years old," he said.
"It was a mistake; it was an honest one. It's like if you made a right turn but you didn't turn your blinker on, they can write you a ticket, and the letter of the label is law," he said, referring to the Diuron label that prescribed the allowable number of applications.
He said the experience of being investigated was good for the company because it was encouraged to pay even closer attention to operational details.
Before the county's findings came to light, residents had suspected something was amiss when they noticed plants on Strawberry Hill behind Gunn had not grown back as of last spring.
"You can see that the dead grass has been through summer, fall and winter rains. It was killed last spring (in 2006) and has not regrown," said Channing Chrisman in a March 12 letter to the state Department of Pesticide Regulation.
The letter spurred an investigation that revealed district Operations Supervisor Chuck McDonnell had initially concealed which chemicals were sprayed. For a March article about the area's defoliation, McDonnell told the Weekly that only Roundup had been used. He did not mention Diuron or No Foam B.
Chrisman, a retired contractor and rancher familiar with agricultural chemicals, cited the article and disputed McDonnell's claim in his letter.
The grass "was not killed with Roundup," Chrisman wrote.
In a May statement to county agricultural biologist Matthew Beauregard, who conducted the investigation, McDonnell admitted he knew the combination of three chemicals had been used.
"I told the reporter only Roundup was used because I was nervous and hadn't talked with a reporter before. ... I knew a surfactant and a pre-emergent had been used along with Roundup," McDonnell said in the statement.
Contacted this week, McDonnell declined to comment on the incident. Pearne, who supervises McDonnell, was unaware of it when contacted by the Weekly.
The omission was out-of-character for McDonnell, who is forthcoming and trustworthy, said Barron Park resident Winter Dellenbach. He has been very responsive to neighbors' concerns about Strawberry Hill, she said.
Letter writer Chrisman agreed and said he trusted both McDonnell and the spraying company to commit no further errors.
"I wouldn't change Chuck, and I wouldn't change the pest service. I would rather have someone who's had that experience and is being attentive and trying to fix it now," he said.
The county investigation that uncovered McDonnell's omission also found Evans West Valley Spray had committed a paperwork violation by failing to document the total acreage treated.
Pearne said that herbicides were mainly applied along fence lines at schools, and the extensive defoliation of Strawberry Hill was an exception. Large-scale spraying there was part of fire precautions, he said.
But the school district should have mowed the land rather than spraying, Chrisman said. Only weeds have begun to grow back, and the district should restore other vegetation, he said.
"I feel they killed the hill, and they owe the community restoration of the hill," he said.