Analysis: Did Council Address the Air Quality Issue?

As issues went in 2016, the issue of air quality was not the top reason or even the runner up reason why Nishi failed.  Clearly the traffic concerns dominated, and the lack of affordable housing was enough to convince key constituents – who would otherwise have supported the project as a way to provide student housing – not to vote for it.

However, with the developers effectively removing both issues from the table, air quality looms as the last remaining key issue.

It was important enough that the developer used his presentation to bring forward Charles Salocks, Don Shor and Larry Greene to address the issue head on.

Dr. Thomas Cahill would respond via public comment, but then the developer also had a chance to respond.

Dr. Cahill told the council that they have scary models and literature that shows harmful health effects from aerosols, “but we have no data at all on site to actually confirm or deny these models.

“I believe that you have to have on-site data on the Nishi site to allow us to go ahead and make an intelligent decision about the role of housing,” he said.

He explained that three years ago he offered to assist the developers by making measurements on the Nishi site.  “It was accepted and several measurements were made,” he said.  “They started doing the work, but it was too short a time, they couldn’t finish it in time for the vote.”

Dr. Cahill said, “For the next two years, at any time, the developers could have contacted me – I was willing to lend them $50,000 worth of hardware, access to our accelerator at Stanford, trained personnel that could do the work and lay this question down early.  It wasn’t done.

“So now we’re in the same situation again to make a decision on the kind of threats there are on site.  In the last two years it hasn’t gotten any better,” he said.  “The good news out of Detroit is the cost of doing ultrafine studies has gone down by a factor of two.  Now it will take about $30,000, a loan of equipment from UC Davis, access to our accelerator at Stanford and some personnel who could do it.”

He said, “Within a year, we could be sitting right here and the city council and the planners… could have in their hands the kind of data you need to make a really sound decision about what the health effects are… about housing at Nishi.”

He recommended to the council to delay the process and give them time to do the studies.

One of the issues that came up on Tuesday is an issue that has been raised in the course of community discussion – whether the city faces liability if someone becomes ill due to air quality at Nishi.

Harriet Steiner explained, “Anyone can file a lawsuit that they think has merit.  I’m not aware of any grounds on which to hold the city liable for approving a land use development application on those grounds.  They might file a suit but I can’t think of a reason why it would be successful.”

Charles Salocks who just retired from Cal EPA with 35 years of looking at the toxicity of chemicals and health risk assessments explained in response to Dr. Cahill’s comments: “There was a screening level risk assessment explained in the EIR – it was very general, very quick.”

This, he explained was based on data from the 10-day study where samples were collected and diesel was the primary concern.  “Diesel particulates are responsible for 70 percent of the cancer risk from traffic related pollutants,” he said.  “The concentration of diesel in the Delta Study was .57 micrograms per cubic meter.”  He said that the statewide ambient level of diesel particulates is .58 micrograms per cubic meter.

“Dr. Cahill’s hypothesis is that the air at Nishi is extremely polluted, it’s much worse than any other area, it’s comparable to Ontario, California.  It’s not.  In fact, the results of that study that were done showed that the air at Nishi was average.  It was almost exactly equivalent to the statewide average for diesel particulates.

“In my mind, there’s no support for saying that this air is particularly polluted,” he said.

A second point Dr. Salocks makes is that “the EIR did not account for the population that we’re looking at here.  The short duration of exposure, the fact that the students are going to be away from their houses for long periods of time – that also enters into the risk assessment process those factors have to be accounted for and they weren’t.

“When you combine all this information – first of all, the air is not worse than anywhere else and secondly the exposure factors when they are incorporated shows that there is very low risk,” he
said.  “I’m not convinced at all that we need to do another study.”

He added, “It certainly surprises me that you need to go off and use a Stanford particle accelerator to analyze your samples.  Because if you do that, no one has ever done that in any risk assessment I have ever look at.  I don’t know what you’re going to use that data for in a risk assessment.  You can’t do that.”

There is also another key point and that is that pollution is down overall, particularly along the I-80 corridor.

Larry Greene, retired from the Sacramento Metropolitan Air Quality Management District, said that the “fleet is getting much cleaner” and the “pollution is coming down because the engines are cleaner.”

Mr. Greene pointed out that “tree barriers were one of the key options for reducing pollution.  They also talked about filtration and also the design of the projects.

“This project in my mind, looking at it, is a very well designed project and incorporates all the recommendations the ARB [Air Resources Board] listed,” he said.  He said that by the time Nishi gets built in 2019-20, the air pollution levels will have been reduced by 90 percent over the levels studied in Southern California from years ago with much higher pollution levels than what we are likely to see into the future.

There is another factor, Mr. Greene explained, the GHG (greenhouse gas) emissions.  “Projects like this that dramatically reduce VMT [vehicle miles traveled] per person, are the type of projects that ARB wanted… to help them meet the greenhouse gas reductions.”

He added that projects like this that get students out of cars and induce them to walk and bike “are really important to improving the health and meeting greenhouse gas goals.”

Mayor Davis also addressed the issue of air quality and especially focused on the health-related ones.

He noted that “there clearly is across the world an association between pollution and poor health outcomes.”  He cited the WHO (World Health Organization), “Locally the impacts are small and they add up to an enormous burden of disease.”

However, “None of these are saying, we need to keep people away from roads.”

He said, “It’s really hard to argue that Nishi represents a departure from what’s happening in our city.”  He said that at night the pollution drifts as much as a mile, “which means that a large chunk of the campus and the city are in those zones.

“We can’t get away from it,” he said.  “So we try to mitigate it.

“What we’re not accounting for is if we do not build housing in this town, we continue to push people onto freeways where the health risk are extremely high,” he said.  “Even with the windows up, driving on the freeway can expose you to pollution levels 5 to 10 times higher than surrounding areas.  That’s the reality.”

Mayor Davis said that the best mitigation is “to build people houses closer to where they work and play.  That’s the solution.  Get people out of their cars…  That’s how we’re going to solve this.”

Mayor Davis concluded that “there is no evidence of increased risk for people living there.  I know I’ll be pilloried for that.  I don’t think additional studies will yield results that will tell us any different.”

None of this seems likely to change people’s minds, but it did inform the council vote and their rationale for putting the project forward to the voters at this time.

—David M. Greenwald reporting

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About The Author

David Greenwald is the founder, editor, and executive director of the Davis Vanguard. He founded the Vanguard in 2006. David Greenwald moved to Davis in 1996 to attend Graduate School at UC Davis in Political Science. He lives in South Davis with his wife Cecilia Escamilla Greenwald and three children.

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  1. Howard P

    Yes… the CC addressed the issue.  As did the EIR and the ‘administrative record’.

    People can choose by their vote.  Everyone can have an interpretation/opinion.

    Just like people can invest money on information available… from the time we are conceived, there are no “certainties” in life… deal with it.  It is what it is.

    If you want zero risk, good luck with that… don’t eat, don’t drive, don’t walk, don’t ride a bike… don’t step outside your home… don’t stay within your home… “don’t drink the water”…

    Even betting on the world turning and the sun being there tomorrow is not “certain”.

    The apparent risk of the air quality at Nishi appears to be far less than a woman choosing to be pregnant… for whether her or the child…  or both… if they live in Davis…

    1. David Greenwald

      I found this interesting:

      “Dr. Cahill’s hypothesis is that the air at Nishi is extremely polluted, it’s much worse than any other area, it’s comparable to Ontario, California.  It’s not.  In fact, the results of that study that were done showed that the air at Nishi was average.  It was almost exactly equivalent to the statewide average for diesel particulates.”

    2. Tia Will


      The apparent risk of the air quality at Nishi appears to be far less than a woman choosing to be pregnant… for whether her or the child…  or both… if they live in Davis…”

      Or anywhere else on the planet for that matter.


  2. Todd Edelman

    In terms of numbers, mitigation requirements in the EIR are very specific: 95% of UFPs (ultra fine particulates, 0.1 microns or smaller) must be removed from interior air. It’s not mentioned, however, if this is with windows open or closed. The EIR mentions several different types of mitigation strategies, including one created in Dr. Cahill’s UCD-based DELTA Group. Cahill told me that in  wind tunnel – i.e. a controlled, laboratory environment – they were able to achieve 98% efficiency with a sort of Frankenfiltration system composed of several different affordable and easily-available filtration products. He added that they’ve only been able to achieve about 70% efficiency in an active location, i.e. a home where people are opening and closing windows, etc.

    At the beginning of the week in a letter published by the Davis Enterprise and the Davis Vanguard, Dr. Salocks said that the filtration would be the state-of-the-art, MERV 13 filters. Well, based on a Google Search, MERV 13 filters have been around since at least 1990. We bought them for our rented home, and while they are an improvement over the typically-installed MERV 8 filters, one of the main reasons we don’t use something better is become normal forced air systems are not designed for them, as they restrict airflow too much (perhaps some fancy residential, commercial and certainly hospital-type facilities can use MERV 14 filters or higher.) MERV 13 filters only remove up to 75% of particles 0.3 micron particles and smaller, and I think it’s a fair guess that they only do 60% of particles 0.1 microns and smaller. (I suspect that MERV 13’s are proposed for Lincoln40 as they can be used with a normal forced-air system.) MERV 15 or higher filters are essentially HEPA-filters, but when installed in commercial HVAC systems they move a lot more air than then even the nice, small HEPA air-cleaners that cost at least $75 each if used most effectively in individual rooms, and which are very loud when on high and working at top efficiency.

    Again, it’s difficult enough to get close to 95% in a lab setting, but even if something close is possible in an apartment with closed windows, it seems beyond hope to consider it likely in an active building. This means that to meet EIR mitigation requirements the apartments have to be sealed, with over-pressuring to deal with doors that are occasionally-open, and fresh air intakes, with filtration on both air from outside and on return/recirculated air. This is very energy intensive, but modern buildings with insulation, south-oriented windows with trees that lose their leaves in winter and solar panels can probably generate what is needed onsite. But it is VERY expensive to do so!

    Do people want to live in this type of building, never being able to open the windows, like in a modern office building or hotel? Let’s be clear: the EIR requires 95%, minimum, for cleaning efficiency.

    About numbers, while the EIR is very specific as mentioned, during the staff overview at Tuesday night’s council meeting the information presented was the interior air would simply be “very clean”.  Related very much to that – it seems – and to the tech that’s supposed to be used to make this happen, shortly before the meeting staff related to me the developer’s answer to my query: “The mitigation measure establishes the standard for filtration, but not the methodology. The exact mechanisms would be verified at the time of building permit. As technology improves, the building designers would be able to adapt to the specific needs of the project at that time, and the tools might very well shift over time.” I hope it is fair to interpret this as “We don’t know what we’re going to use and we hope that it will work a few years from now when he apply for a building permit”.

    I appreciate very much what Don Shor has taught me about the benefits of trees in reducing particle pollution, though it seems results vary. So I am not clear why Nishi was approved for the ballot with 700 parking spaces when that space could be used to nearly double the forest depth. I am not sure how much effective this is compared to what’s claimed for what’s planned, but my guess is that it’s considerably better, not only because it’s thicker, but because particles that go above the treetops etc near the freeway will have to travel a lot further to fully clear the floral fence.I don’t doubt what Robb Davis said about reducing VMT as a very important goal, but in regards to

    None of these are saying, we need to keep people away from roads

    the CDC – in “Residential Proximity to Major Highways” from 2010 says that there are benefits from “… land-use policies that limit new development close to heavily-trafficked roads.”

    1. David Greenwald


      I think your points are reasonable here, but let’s suppose in real life you can only retain a 70% reduction – that seems reasonable.  But when you have the filtration system combined with vegetation barriers, and account for the fact that most places have neither filtration nor vegetation, you’re still probably ending up with better air quality than most places within a mile of I-80

  3. darelldd

    The traditional way of dealing with the pollution and congestion created by motor-vehicle traffic is to… accommodate it in any way possible. Add more lanes. Put up walls. Filter the air in buildings.

    Well, Robb put it best: “Get people out of their cars…  That’s how we’re going to solve this.”

    If we continue to stipulate that we simply need to figure out how to live with the pollution, we can’t solve this. Sure we can measure the air and find out what we already know: Motor vehicles pollute our air and make us sick. THAT’s the part we can stipulate. Now we have a choice: Run and hide from that pollution, or put our effort and money into reducing that pollution.

    I’m getting tired of hearing from Cahill that this can all be solved if only we pay him $30,000 to do measurements that apparently only he can do correctly.

    I have to wonder: If Mr. Cahill is aware that fossil-fueled motor vehicle traffic is deadly, how has he chosen to transport himself? I’ve not yet heard that the people who are most concerned with the air quality are actually doing something to lower that real hazard. (And I can tell you for *free* that it is a deadly hazard!)

    1. Todd Edelman

      Robb also said that we were powerless to change the 80 and 113. Further, while his emphasis on VMT is essentially unassailable, it only really applies generally: Not everyone – in fact, who really knows the numbers? – is going to live at Nishi instead of driving to Nishi inside a polluted car – and Nishi is definitely not the only location these students etc. can be housed: There are multiple sites – farther at least from freeways, if not major roads – for infill development. In my full letter to the Council before the meeting, I suggested that we focus on these for now – until the medium-term when Nishi is more fully habitable – as well as see what we can do as a community without formal jurisdiction about making the highways cleaner. (To the last point as a Commissioner I am tonight – at our meeting at 5:30pm at the Senior Center – proposing the creation of a sub-committee in the Bicycling, Transportation and Street Safety Commission.)

    2. David Greenwald

      I think you nailed it (as did Robb).  The best answer is to get people out of their cars and the best way to do that is put housing next to jobs.  That means that developments like Nishi are the solution, not the problem

      1. Ron

        This response (which has been repeated by other Nishi supporters) fails to note the effort to ensure that UCD takes responsibility for the demand that it’s “creating” (primarily via pursuit of non-resident students).

        What a load of crock, regarding the presentation (quoting the chancellor, as I recall), at the council hearing. Who cares, regarding what he thinks?

        There is a failure (on the part of many in the city) to recognize what’s going on, here.  Too many people view UCD as a “partner”, instead of an organization that’s foisting impacts on the city (and on its own students) for its own benefit.  Perhaps too many people have a direct connection to UCD, to recognize this.

        There’s reasons that two other cities have initiated actions regarding UCs. However, those cities have “something else” other than a UC to their credit.

        1. David Greenwald

          I don’t see anything mutually exclusive between supporting a housing project that provides needed housing and also attempting to get UC Davis to build more housing on campus. In fact I thought Will Arnold’s comments on Tuesday that it is still his goal to get UC Davis to 50% is spot on.

        2. Ron

          Sites on campus don’t have problems regarding air quality that we know of (or costs/impacts to the city).

          To my knowledge, Dr. Cahill has no “agenda” other than air quality.

          “Hoping for” 50%, while simultaneously approving choices in the opposite direction is not a logical or sound plan. Past results already confirm the probable future result.  

        3. Ron

          David:  I don’t know if that’s true, nor do I know if they have the same unique characteristics as Nishi.  (But, I’m not going to engage in repetitive arguments regarding that.)  I would probably refer to a local air quality expert (who hasn’t demonstrated any other “agenda”) regarding those issues.

          In any case, it seems that the political process may have overwhelmed the pursuit of scientific analysis, on the Vanguard and on the council. (Gee, that sounds kind of familiar, at a higher political level.)

          My primary concern remains costs and impacts on the city.

        4. David Greenwald

          You’re view is heavily shaded by one air quality expert.

          Salocks on the other hand, doesn’t believe that Nishi’s air quality is much worse than average.  I’ll be interested to see if anyone other than Cahill believes otherwise.

        5. Ron

          You’re referring to the expert regarding the use of methamphetamines, as noted on the Vanguard?  Certainly someone who knows more than me (regarding impacts on the human body), at least.  Regarding air quality testing/methods, I’m assuming that he has no experience.  (And yet, there he was, commenting on such factors via his Vanguard article.)

          From what I can see, politics is interfering with the completion of scientific analysis (in which results are reviewed somewhere other than on a blog). And yes, that would include any valid/scientific criticisms or limitations from actual peers, as well.

          Again, I don’t like commenting on this issue, since I’m not trying to use it as a political weapon (one way, or another). Therefore, I have not “researched it” with that purpose in mind, and have only casually followed the issue.

        6. David Greenwald

          Salocks was chief toxicologist for Cal EPA in the Office of Health Hazard Assessment and is an expert in environmental toxicology and health risk assessment.

        7. Ron

          O.K. – that does provide some more broad-based information. Not very specific, regarding his reviews of air quality research.

          But again, has he ever conducted an air quality study as part of his professional career?  If not, why would he be uniquely qualified to discuss factors regarding such studies (e.g., wind direction, site characteristics, etc.)?

          And again, is a blog the appropriate place to engage in scientific research and review? (Let alone “conclusions”?)

          1. Don Shor

            has he ever conducted an air quality study as part of his professional career? … why would he be uniquely qualified to discuss factors regarding such studies….

            Regulatory scientists take the research done by others, weigh the evidence, assess the risks, and determine how to apply that data in the real world.

        8. Ron

          The guy who is an expert in such research has essentially told us that his work is not complete, and is therefore not ready to be reviewed by others. (And, it’s not likely that such work would be scientifically reviewed via blogs.)

          And yet, he’s apparently offered to complete such analysis, for the past couple of years.

          Perhaps some don’t want to know the results, if allowed to proceed.

          What a load of b.s. The guy was allowed three minutes, vs. whatever the development team was allowed. Political process at its finest.

          1. David Greenwald

            What you seem to be missing is that Dr. Cahill is engaged in a political process that has nothing to do with science. That is what his supporters are in denial about. You’re completely unwilling to listen to what non-Cahill experts tell you.

        9. David Greenwald

          “And again, is a blog the appropriate place to engage in scientific research and review?”

          You keep raising this point and it’s bullshit.  This is an election.  This website is a place where people who live in this community have a discussion.  It’s not the only place, but it is a place.  If you have something to contribute, then speak.  But yes, this is the appropriate place to engage in this conversation.

        10. Ron

          I have been speaking – thanks.  Yes, there’s a discussion, but not much science.  At least, not much directly related to the site. 

          Scientific research and review is generally not conducted via blogs. (Perhaps “Tweets” at some higher levels, but not blogs.) 🙂

        11. Tia Will


          Too many people view UCD as a “partner””

          Or maybe some see this as an aspirational change in relationship. I would love to see the university and the city work together collaboratively on mutually beneficial projects. I see providing affordable housing for students as one area of possible collaboration.

  4. Todd Edelman

    most of the sites on campus are also in the same range of distance to the freeway as Nishi.

    Guess again! Seriously, that makes no sense at all. I suppose you are referring to the ambient pollution levels?

    Anyway, the arguments that Nishi is no worse than anywhere else, or that there’s so much pollution already that Nishi doesn’t add much seem to ignore the EIR mitigation requirements based on the accepted fact that is IS more polluted here. I’ve already been as clear as possible that the interior air mitigation itself is impossible due lack of efficiency of air filtration systems, a sort of delusion that residents will sense the need to close windows when virtually invisible particles are aiming for their bloodstreams, and near- to medium-term reluctance and technical struggle of the managers and users of the I-80 to make the freeway and its municipal feeders a cleaner mechanism.

    1. Ron

      Todd:  One thing that probably gives you more “credibility” than most commenters (regarding this issue) is that you’re not viewed as someone who is “against” development.  Plus, you seem to have an honest interest regarding this subject.

      Personally, I mostly just object to the political process overwhelming the scientific process.  The scientific process has not been completed, apparently despite offers to do so over the past couple of years.

    2. Tia Will


      I have read all of your posts and agree that there are some valid concerns. However, life is full of risks and I am not sure that this particular risk outweighs the risk of increased commute, often by car, or even the risks incurred in riding your bike for longer distances.

      There is another form of “mitigation” that has been mentioned briefly by some and that is providing warnings for potential residents. I would suggest warnings prior to rental as full disclosures just as is supposed to be provided to potential home buyers. Further warnings could be provided to leave windows closed on “high risk days” encouraging residents to leave their windows closed. We have ample precedent for this approach in terms of alerts of “spare the air” days and “no burn days”. Presumably the students are literate and could be sent alerts via their smart phones or emails.

      Your thoughts on this approach would be appreciated.

  5. Howard P

    Must have missed it… when was the “methamphetamine expert” crack (pun intended) made?  By ‘prof’ Cahill?  [‘Prof’ seems to mean ‘professor rather than ‘professional’…]

  6. Howard P


    “Charles B. Salocks, an expert on methamphetamines…”


     “the expert regarding the use of methamphetamines, as noted on the Vanguard…”

    Why the embellishment? [embellishment is the most charitable term I could think of… another term comes to mind]

    1. Ron

      Howard:  I’m failing to see the difference, embellishment, or outright lie.  I would think that virtually all research regarding methamphetamines involves the impact of usage.

      No “reasonable” person would assume that anything else was intended. (Note the qualifier I used in the previous sentence.)

      Actually wondering why you’re bringing this up again, since I recall that you commented on it previously (in the other article which mentioned Dr. Salock’s area of expertise).

      1. Ron

        Note that Howard initially used the words (or something close to) my first sentence above.  (Otherwise, I would not have referred to them, and they now appear to be “out of place”.)

        Howard’s comment was subsequently changed, probably during the “grace period”, after posting a comment.

    2. David Greenwald

      In fairness Howard, my issue is with Cahill, not Ron on this one.  Cahill has at best under-recognized Salock’s expertise as senior toxicologist for Cal EPA and health risk assessment by highlighting some of Salock’s research on safety precautions for cleaning up meth labs.

      1. Ron

        Personally, I don’t think that Cahill’s post on the Vanguard was that well-written.  (One of the potential problems with participating on a blog, especially if one pays attention to attacks day-after-day.)  But, in all honesty, I doubt that it would make much difference.  The council seemed to have made up its mind a long time ago, regarding its preference for Nishi.  (They previously did so with Nishi 1.0, as well.) The actual decision was rather anti-climactic.

        Running it half-assed through the commissions was a waste of time and energy, regarding the council’s decision at least.

  7. Howard P


    “******’s comment was subsequently changed, probably during the “grace period”, after posting a comment.”

    Aka, self-moderation… good feature… saves the moderators grief (and gives the poster ‘reflection time’)… if one can wait for 5 minutes before responding… no issue…

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