The risk of adverse health effects from the Lehigh Southwest Cement Plant on Los Altos and Los Altos Hills residents is small, a consultant retained by the cities has reported.
It will be discussed at a public forum on Monday in the Los Altos Hills Town Hall, 6 to 8:30 p.m.
"The paraphrased opinion is that, while not zero, the estimated health risks to Los Altos Los Altos Hills residents due to the quarry’s emissions are considered to be small," said Los Altos Hills Vice Mayor Gary Waldeck. Waldeck, with Los Altos City Council members Ron Packard and David Casas formed an ad-hoc committee to investigate concerns raised by residents of both communities.
The consultant, Iris Environmental of Oakland, was hired for $28,000 to assess available Lehigh quarry test data and to deliver an independent analysis and opinion of the results.
Waldeck said no analysis was made or offered for other locations, such as the cities of Cupertino, which is adjacent to the quarry or to Mountain View, through which Permanente Creek flows toward the Bay.
Iris Environmental reported that they also examined the test methodologies used by the Regional Water Quality Control Board, Bay Area Air Quality Management District, and Lehigh’s own data collection methods. Iris agreed with the procedures used. They also examined the wind dispersion model used to predict the plant’s airborne effluent dispersion patterns and concurred in its usage as well.
Lastly, they collected and analyzed one water and one sediment sample taken from Permanente Creek at a site downstream from the quarry.
Though a single sample is not sufficient to come to a conclusion, the intent was to obtain a snapshot of the environment near the quarry to help independently assess the veracity of other data, Waldeck said.
Iris Environmental also cited and considered existing management district directives applied to the quarry and suggested continued monitoring to ensure that systemic upgrades continue as planned, Waldeck said.
Representatives of Regional Water Quality Control Board and the Bay Area Air Quality Management District will be on hand at Monday's meeting.