SUMMARY OF KEY POINTS
A Regional Anomaly: Unlike open wind corridors (such as San Carlos), the Councils proposed multi-year project operates at zero-lot-line proximity (under 20–50 feet) to residential bedroom windows across three separate 75-year-old toxic soil sites.
The Air Trap Micro-Basin: Downtown Menlo Park’s street canyon geography acts as an air trap, preventing the dispersion of fine particulate matter (PM 2.5), lead dust, and diesel exhaust—bypassing standard CARB/BAAQMD 300–500 ft health buffer guidelines.
Direct Biological Risk: Over 6,600 residents within 1/2 mile—along with downtown workers, outdoor diners, children, and pets—face a multi-year cumulative toxic load with zero recovery windows between excavation phases.
Dear Mayor Nash and Council members,
The proposed downtown parking-lot housing project is unprecedented for Menlo Park; its specific combination of local risk factors makes it a public health outlier by any regional standard.
When you evaluate housing developments across the Peninsula, you will find projects with single-year construction windows, projects with 300 to 500-foot buffer zones as recommended by CARB and BAAQMD, or projects along open, wind-swept transit corridors.
What you will not find anywhere in the Bay Area is a project that combines all four extreme public-health risk factors at once:
· a 5-year continuous buildout,
· zero buffer between the lots and dense nearby housing, with some residences and businesses sitting under 50 or even under 20 feet from the construction sites
· 75 years of un-remediated soil contaminants,
· and a downtown “micro-basin” that traps airborne pollution.
That specific combination makes this project a dangerous regional anomaly: it turns a residential neighborhood into a five-year public health hazard.
Here’s a quick comparison between San Carlos’ project and Menlo Park’s proposal that I wrote up as follows:
Exhibit 1: San Carlos (Wheeler Plaza): That project replaced a standard downtown municipal surface lot and a mix of minor underutilized parcels that had relatively modern turnover and standard municipal use footprints.
In stark contrast, Menlo Park Plazas 1, 2, and 3: These specific plazas have been heavily trafficked, urban core surface lots for over 75 years.
The Distinction: Seventy-five continuous years of urban surface parking means deep layers of packed substrate laced with decades of cumulative automotive toxins—leaded gasoline residues from pre-1970s vehicles, heavy motor oil seepage, industrial cleaning solvents, and weathered coal-tar sealants.
When you excavate San Carlos, you are digging up standard modern fill; when you excavate 75-year-old downtown Menlo Park plazas, you are turning over a multi-layered historical archive of heavy metals and petroleum hydrocarbons.
Exhibit 2: San Carlos: Situated along broader commercial corridors with open-sky configurations and steady regional wind patterns that naturally shear away and dilute dust and exhaust plumes.
In sharp contrast, Menlo Park Plazas 1, 2, and 3: Flanked immediately to the west and south by dense, multi-story apartment complexes forming tight urban street canyons.
The Distinction: Menlo Park’s downtown core acts as a "micro-basin" air trap. Heavy construction dust (PM 2.5) and VOC vapors dont blow away freely here—they pool and stall against zero-lot-line residential windows.
San Carlos sits in an open flatland corridor with steady marine breezes that disperse emissions. But localized developments built in constrained spaces like ours suffer from a lack of dispersion paths. Our downtown corridor, boxed in by dense multi-family apartments to the south and west, acts as an air trap. Heavy dust particulates (PM 10) and dense VOC vapors do not magically float away; because they are heavier than clean air and blocked by surrounding buildings or terrain features, they pool at ground level.
Exhibit 3: San Carlos: Handled as a single, contained site development phase lasting roughly a year to 18 months. Once it was built, the disruption ended, and the neighborhood returned to baseline.
Differing even more dramatically, Menlo Park: Proposes a staggering 5-year rolling, multi-plaza buildout, which is likely to go on even longer.
The Distinction: A 1-year project is an acute disruption that a community absorbs. A 5-year continuous construction marathon across three adjacent plazas means residents are subjected to unyielding, daily industrial activity without a single seasonal window of recovery. It changes the neighborhood from an active downtown into a half-decade industrial extraction zone.
When you combine 75 years of undisturbed legacy soil, zero physical buffer, and a 5-year rolling excavation schedule, you arent building in a parking lot in an open wind corridor like San Carlos. Youre creating a localized particulate and chemical basin right outside peoples bedroom windows with nowhere for the pollution to go but into their lungs.
Snapshot of health impacts of chronic exposure to particulate pollutants:
Deep Tissue Penetration PM 2.5: Microscopic dust particles PM 2.5 penetrate deep into the pulmonary air sacs and enter the bloodstream. Unlike coarse dust, the body cannot easily cough up or filter fine dust.
Decreased Lung Function: Long-term exposure to ambient construction dust is linked to measurable, permanent reductions in lung capacity. In growing children, chronic exposure can actually stunt full lung development.
Cardiovascular Stress: Particle pollution in the bloodstream triggers systemic inflammation, which is clinically linked to an increased risk of high blood pressure, irregular heartbeat, and cardiovascular stress in elderly populations.
Specific Toxic Constituents: If the excavated soil contains legacy lead, silica from concrete grinding, or heavy metals from decades of vehicle wear, those specific toxins carry their own cumulative cellular toxicity risks
And per Mayor Nash’s request during Sunday’s gathering in the farmers’ market, below are the formal medical and regulatory citations establishing the health risks associated with continuous, multi-year airborne particulate exposure and toxic chemical off-gassing near dense residential areas.
Statement 1: Continuous Particulate Exposure & Long-Term Lung Damage
"A 5-year continuous construction timeline exposes nearby residents to sustained, daily particulate and chemical insult without a recovery window, increasing the risk of chronic, irreversible damage (such as pulmonary fibrosis or accelerated lung function decline).”
Primary Evidence & Citations:
1. U.S. Environmental Protection Agency (EPA) – Integrated Science Assessment (ISA) for Particulate Matter:
o Reference: U.S. EPA. Integrated Science Assessment for Particulate Matter (Final Report).EPA/600/R-19/188.
o Key Finding: The EPA’s formal health assessment concludes that multi-year exposure to fine particulate matter (PM2.5) causes accelerated loss of adult lung function and impairs lung growth in children. It establishes that long-term exposure induces chronic pulmonary inflammation leading to irreversible tissue alteration.
2. American Thoracic Society (ATS) – Annals of the American Thoracic Society:
o Reference: Sack C, et al. Long-Term Air Pollution Exposure and Progression of Idiopathic Pulmonary Fibrosis. Ann Am Thorac Soc.
o Key Finding: Peer-reviewed clinical research links long-term exposure to ambient fine particulate matter (PM2.5) and vehicle-related nitrogen oxides directly to the progression and severity of pulmonary fibrosis and permanent loss of forced vital capacity (FVC).
3. California Air Resources Board (CARB) – Health Effects of Airborne Particulate Matter:
o Reference: CARB Fact Sheet: Health and Environmental Impacts of Particulate Matter PM 2.5 and PM 10
o Key Finding: CARB identifies that while short-term spikes trigger acute events, cumulative daily exposure without adequate recovery windows leads to permanent structural remodeling of lower respiratory tract tissue and long-term loss of lung elasticity.
Statement 2: Classification of Diesel Fumes and Soil Contaminants as Toxic
"Diesel exhaust fumes and volatile organic emissions from legacy soil disturbances are formally classified as Toxic Air Contaminants and known human carcinogens.”
Primary Evidence & Citations:
1. California Environmental Protection Agency (CalEPA) & CARB:
o Reference: Title 17, California Code of Regulations, Section 93000 – Identification of Diesel Exhaust as a Toxic Air Contaminant.
o Key Finding: Under California law, Diesel Particulate Matter (DPM) is formally designated as a Toxic Air Contaminant (TAC) based on extensive epidemiological data demonstrating its carcinogenicity and severe respiratory toxicity.
2. World Health Organization (WHO) – International Agency for Research on Cancer (IARC):
o Reference: IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 105: Diesel and Gasoline Engine Exhaust and Some Nitroarenes.
o Key Finding: The WHO formally classifies diesel engine exhaust as a Group 1 Carcinogen—the highest threat category, placing it alongside asbestos, benzene, and tobacco smoke as a proven cause of lung cancer in humans.
3. U.S. Agency for Toxic Substances and Disease Registry (ATSDR) / CDC:
o Reference: Toxicological Profile for Toluene and Volatile Organic Compounds. U.S. Department of Health and Human Services, Public Health Service.
o Key Finding: Inhalation of volatile aromatic hydrocarbons (VOCs like toluene and benzene) directly causes central nervous system depression, mucous membrane inflammation, and acute airway irritation.
Public health science is clear: exposure to fine particulate matter and toxic air contaminates isn’t just an annoyance—it causes irreversible loss of lung function in healthy adults and carries a documented risk of premature mortality for elderly and vulnerable residents. The proposed 5-year toxic burden without a recovery window isn’t a standard construction nuisance: it is an extraordinary public health threat.
Mayor Nash and Council members, I urge you to terminate this deleterious project, and reach out to HCD to let them know the city tried very hard to make this project work, but we’ve discovered that it would endanger the health of our residents to the extent of causing them irreversible lung damage that will impair and/or shorten their lives, and we aren’t willing to inflict five years or more of toxic air pollution on an entire community over this housing project.
We’ll find other, safer sites for it.
Sincerely,
Cherie Zaslawsky
