For many residents, the most infamous aspect of Milpitas history involves the putrid odor that has spread throughout the city for years. The odor has been a longstanding concern for the community, existing for over 100 years and carrying a long history…
There are multiple things that are complicating this issue. First is the multiple sources of air pollution: the three main areas being the Newby Island Resource Recovery Park (NIRRP), the Zero Waste Energy Development Company (ZWEDC), and the Regional Wastewater Facility (RWF). Due to all of these facilities being so close to each other, it’s a complicated process to categorize which odor comes from which facility.
The second thing that complicates the issue is the authority of the facilities. They all sit within the San Jose-to-Milpitas border, with ownership belonging to the City of San Jose. Due to Milpitas not having any leverage over the facilities, it has been difficult for our City to control issues regarding them.
However, this has not stopped the Milpitas City Council from trying; there have been multiple attempts over the years. One example is some actions taken during Bob Livengood’s term as Mayor. During Livengood’s term, the City Council tried convincing San Jose to annex their authorization of the landfill and give the authorization to Milpitas. However, San Jose refused to do so.
Along with the actions taken by the Council, there have also been efforts by the community to regulate the odor. While the community has lived with the odors for several decades, its movements truly came to life during the late 2000s through the 2010s, when community members began to organize opposition toward the odor – specifically toward the NIRRP landfill. While this organized opposition did not do much in terms of creating change in odor regulation, it was revolutionary in publicizing the existence of the issue. As Bob Livengood stated in an interview, “I can’t think of any kind of city where their residents were putting signs on their front lawn saying, ‘Hey if you smell an odor call this number…’”
There have been more recent actions by the City Council to mitigate the odors. These actions have come in the form of two studies: the Community Odor Monitoring study led by the Milpitas City Council and the Odor Attribution Study led by the Bay Area Air Quality Management District (BAAQMD).
The main objective of the Community Odor Monitoring Study was to gather objective data on the odors. With funding approved for a pilot program in Spring 2019, the project took place from late 2021 through early 2022. Some of the methods used for collecting data involved field odor assessments and bag supplies. The study also contracted with Jacob’s Engineering Group, a company specializing in odor issues. The team also collected point-in-time odor readings using a field olfactometer. In the end, a total of 50 field odor assessments were taken at 11 discrete locations over 18 months (this was extended from 12 months due to the COVID-19 pandemic; however, there were no significant differences pre- and post-pandemic). An average of 2 assessments were conducted every 3 weeks, resulting in a total of 580 field observations.
The main objective of BAAQMD’s Odor Attribution Study was to link the attributed odors to specific sources. In the end, they were able to attribute the odors to the aforementioned three facilities: NIRRP, ZWEDC, and RWF. However, the proximity and the similarity of the three facilities made it difficult to trace the odors to one specific facility. Therefore, they spread their field sampling and data collection over three seasons to better identify the odor components.
It’s important to note that BAAQMD has voiced concerns over the odor in relation to health. According to an email from BAAQMD, exposure to odors can result in temporary and reversible health symptoms. Some symptoms that can appear during especially strong odor events include eye, nose, and lung irritation, as well as a burning sensation that may lead to coughing, wheezing, or other breathing problems. The odors can also cause nausea, headaches, and dizziness. If these odors last for a long enough period of time or keep occurring, they may also affect one’s mood, cause anxiety and/or depression, cause an increased stress level, or lead to a reduced quality of life for those affected.
Both studies confirmed the existence of the odor issue in Milpitas with objective data. The Community Odor Monitoring Study found that there was not a single prominent odor expressed by residents in the community. The odor experienced depends largely on the location, wind direction, and time of day. The Odor Attribution Study concluded that all three waste facilities have contributed to the odor. Specifically, NIRRP contributes through the landfill, material recovery facility, and composting operation. ZWEDC contributes through their composting. And RWP contributes with their sewage, sludge ponds, and drying beds.
Now that both studies have concluded, the main strategy presented by the City Council involved setting up an Odor Reduction Ad Hoc Sub-Committee, which recently started meeting. The sub-committee agreed that they would work with regulators and odor-contributing facility operators to improve Milpitas’ air quality. The sub-committee will be looking closely at the two studies in an effort to collaborate on next steps.
There are also solutions being proposed by BAAQMD for the facilities. Their proposals include repairing leaks by installing or repairing air curtains at the door openings and establishing negative pressure zones in key areas. Another action includes monitoring carbon filters more closely and improving the relevant system for quick changeovers. They can also add landfill gas collection wells, as well as more frequently monitor wells with handheld sensors. And when there are leaks, the facilities can make more expedient repairs. Finally, they can utilize operations involving flow, mixing, or aeration to dedicated abatement equipment.
Meanwhile, BAAQMD has reached a settlement with NIRRP regarding violations in the facility. Some of the violations by NIRRP include landfill leaks during composting operations in 2014 and 2015, wellhead positive pressure violations between 2015 and 2019, gas collection system shutdowns in 2019, and notices of public nuisance from 2014 through 2016. Since the settlement, all of these violations have been fixed, and NIRRP also agreed to pay $210,000.
As a message to Milpitas residents on the issue, Mayor Rich Tran shared, “We have a high-level strategy in place and results are coming soon.” He also stated, “I’m hopeful that through our efforts as a Milpitas community and City government, we can clean the air.”
Over email, the directors of the Odor Monitoring Study asked Milpitas residents to “Please continue to report odor issues to the BAAQMD and be as specific as possible when reporting the type of odor and what you are smelling.”