Guest Commentary: Air Quality Critic Gets Analysis Wrong on Nishi

By Charles B. Salocks

I have reviewed the environmental impact report for the Nishi property and some of Tom Cahill’s comments concerning air quality, and have reached the following conclusions:

* There is no scientific basis for concluding that air quality at the Nishi site, as influenced by freeway traffic, is any different than at other residential locations, existing and proposed, along the Interstate 80 corridor in Davis.

* Meteorological data from the UC Davis Airport indicate that the predominant wind directions are from the north and the south. The elevated portion of I-80, which Cahill has cited as a potential source of braking emissions, is southwest of the Nishi property. The wind comes from this direction just 5 percent of the time, meaning that emissions from this portion of the freeway will affect Nishi residents very infrequently.

* There are no geographic barriers to impede the dispersion of traffic-related pollutants. The Nishi site is not an area where these pollutants would be expected to concentrate unduly. In fact, the elevated section of roadway will result in greater dispersion of traffic-related contaminants than would occur if the residences were at the same grade as the freeway (L.A. Times, Dec. 30, 2017).

* Health risk estimates presented in the draft EIR for the original Nishi development was based on several incorrect assumptions. Updating the risk estimates with assumptions that actually reflect
the type of housing proposed for Nishi 2.0 would result in a proportional decrease in the long-term health risk. These assumptions include the following:

— The EIR assumed a 70-year exposure duration. Nishi 2.0 residents are expected to live no more than three to four years in this location. Accounting for this difference alone would reduce the long-term health risk by 95 percent.

— The EIR did not account for the amount of time a resident spends indoors, where the air is filtered. The health evaluation for the New Harmony housing project (immediately south of I-80) included an assumption that people spend on average about 22.5 hours per day indoors.

— The risk estimates did not account for the amount of time a resident will spend away from his or her home. California EPA risk assessment guidelines recommend a default assumption that residents spend 27 percent of the time away from their home, although this figure may be too low for most UC Davis students.

* The EIR did not consider the extensive mitigation measures planned for the current proposal, including:

— The building design incorporates a state-of-the-art indoor air filtration system (MERV 13) that will eliminate most of the airborne particles.

— A 100-foot-wide continuous urban forest with plant selections based on filtering qualities applicable to fine particulate matter will be planted between I-80 and the Nishi site. According to research conducted by Cahill and others, these green barriers will reduce particulate concentrations by 79 to 99 percent.

— With satellite parking and no driveways within building clusters, the tree canopy will be more extensive and will result in additional filtration of airborne particles.

— Only about one-third of the students will have cars. This reduces opportunities for “cold” starts, a major source of automobile pollution.

* Many UC Davis students currently drive to campus in automobiles. Recent research indicates that commuting in a car on the freeway exposes you to pollution levels that are five to 10 times higher than the surrounding areas. If these students have the option of living in a location immediately adjacent to campus, they can bike or walk to class, and avoid the traffic-related pollutants that can be detrimental to their health.

I’d like to add a few thoughts about the commentary in the Jan. 24 edition of The Davis Enterprise, in which Cahill attempted to make the case that the Nishi property is “… in the running for the most polluted near-roadway site in the nation.”

Cahill’s argument is based largely on a comparison of daily traffic data for I-80, which is adjacent to Nishi, and I-60 in Ontario (San Bernardino County), which has been labeled “the worst near-freeway site in the entire USA.” This comparison is faulty for the following reasons:

* The monitoring station in Ontario is located 30 feet from I-60 (L.A. Times, Sept. 9, 2015). The residences at Nishi 2.0 will be located 350 to 750 feet from I-80 and will be screened by a 100-foot-wide urban forest.

* The prevailing winds in Ontario are from the west, and most of the Los Angeles air basin lies west (upwind) of Ontario. This means that all the air pollutants from the most densely populated cities and the most heavily traveled roads in the L.A. air basin, as well as the ports of Los Angeles and Long Beach, funnel into Ontario.

At Nishi, residents may be exposed to a low level of traffic-related pollutants that make it through the urban forest filter when the wind blows in from the south. But what lies farther upwind of I-80? Agricultural land and the Sacramento/San Joaquin Delta.

And consider this: All of Cahill’s traffic data are applicable to the entire stretch of I-80 that passes through Davis, from Highway 113 to Mace Boulevard and beyond. Fortunately, there is no basis for concluding that the air at the Nishi property — or any other property along the I-80 corridor in Davis — is one of the most heavily polluted places in the nation.

In summary, the mitigations being taken by the Nishi project are, in my opinion, comprehensive and also will protect other nearby residential properties. We hope that Nishi 2.0 will provide a model for mitigation strategies that can be adopted at other residential projects in Davis.

The utilization of infill properties such as Nishi, appropriately labeled “smart growth,” is an important element in the ongoing effort to improve air quality for everyone.

— Charles B. Salocks, Ph.D., a Davis resident, is a retired senior toxicologist with the Pesticide and Environmental Toxicology Branch of Cal/EPA, Office of Environmental Health Hazard Assessment.



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36 Comments

  1. Ken A

    It is going to be interesting to see the people that hoped the “toxic soup” lie would kill Nishi respond and argue that Cahill was correct in his assumptions that most people who move in to a Nishi apartment will live there for at least 70 years and spend most days running laps around the site breathing in auto exhaust and diesel smoke from trains…

  2. Tia Will

    Ken

    I do not believe that this was so much a “lie” as a difference of perspective. The “toxic soup” group are correct that pollutants do exist. It is entirely possible that their assessment of acceptable risk is simply different from yours, and mine for that matter. Two considerations that have often been missing from their analysis are comparison to the risks incurred by not having housing in close proximity to the university ( the do nothing alternative) , and the epidemiology from the surrounding areas ( Olive Drive housing) which does not support ( at least in acute respiratory illnesses) an increased risk. It is my belief that these also should be considered in the analysis as should a realistic risk assessment which is not reflected in Dr. Cahill’s assertion that one death is too many which over looks the risk of commuting over a 70 year period which is the time line for increased cancer deaths.

      1. Tia Will

        I presented the bare bones summary of information from the county epidemiologist at the time of Nishi 1. There wasn’t much to report because there was no increase in ER visits for respiratory illnesses along the I-80 corridor from Vacaville to as far east as West Sacramento where the first increase was noted. I do not have the updated numbers since she has been out on an extended leave. I do not expect any changes from two years ago.

    1. Ken A

      If you don’t think it was a “lie” do you think that the air at the Nishi site meets the definition of “toxic”:

      “containing or being poisonous material especially when capable of causing death or serious debilitation”

      or that the air at the Nishi site is like a “soup”:

      “something (such as a heavy fog or nitroglycerine) having or suggesting the consistency or nutrient qualities of soup”?

      As Howard mentioned last week some people spend lots of their free time for years working on air quality issues, affordable housing or ground squirrel habitat, while others just pretend to care about those issues and will say anything if they think it will help to kill development in town (in the hope of keeping property values and rents high while continuing the decades long gentrification trend where poor people keep getting pushed out of Davis).

      1. David Greenwald

        I think Don probably has explained this pretty clearly – there is a higher particulate matter quantity than you would like but there are ways to mitigate that and it is unclear with a one to three year exposure what that would mean health wise and that issue lies well outside of Cahill’s expertise.

      2. Tia Will

        Ken

        I do believe that there are “toxins” in the air tested from near the Nishi site. I believe that the phrase “toxic soup” was hyperbole, not a “lie”. I do not agree with the conclusions of those who feel that this site is hazardous ( especially once mitigated) , but I do believe that many of them are sincere in their concerns.

  3. Ron

    Tia:  “Two considerations that have often been missing from their analysis are comparison to the risks incurred by not having housing in close proximity to the university ( the do nothing alternative) , and the epidemiology from the surrounding areas ( Olive Drive housing) which does not support ( at least in acute respiratory illnesses) an increased risk.”

    As previously noted, the “do nothing” alternative is not the only other choice.  For example, there is an adjacent 5,300 acre land-mass that already includes some student housing, and which could house more.  Coincidentally, it belongs to the same organization that is creating the need for more student housing, primarily by pursuing students who can pay them $42,000 for tuition. The reason for their reluctance to house students has never been explained, but I suspect that it has to do with costs.

    Regarding the Nishi site itself, it has been pointed out that it has some unique characteristics which impact air quality.  (But, I’m not going to argue about that, myself.)

     

    1. David Greenwald

      “Regarding the Nishi site itself, it has been pointed out that it has some unique characteristics which impact air quality. “

      And that’s what Salocks argues against here

      1. Ron

        He does indeed argue that.  However, that doesn’t mean that he’s correct.  Only one of these guys actually specializes in the study of air quality, and it ain’t the author – based upon the credentials listed for both.  (Yes, I realize that the author can comment regarding toxicology, after a study is done.)

        These types of issues are settled by vetted/reviewed scientific research, not on a blog.

        1. David Greenwald

          “He does indeed argue that.  However, that doesn’t mean that he’s correct.”

          But he offers explanations and reasons to back up his argument, something that you do not counter with facts but more assertions about what he does or doesn’t know based on your presumptions about his areas of expertise.

          “These types of issues are settled by vetted/reviewed scientific research, not on a blog.“

          Guess what, this election is going to be decided by voters not scientific journals.

           

          1. Don Shor

            The scientific research tells us that mitigation is possible. The wind rose data tells us that prior assumptions about wind direction and frequency were incorrect. All of the air quality information was also reviewed by Larry F. Greene.
            Just for the record, the geography of the site is actually completely flat and there are no natural barriers to air flow, nor any tall buildings. That was just a matter of looking at a topo map to verify. Under very stagnant conditions it is possible that air would be slightly impeded by the train track elevation to the north, or the freeway to the south (which is pretty irrelevant), but under those conditions of low wind speed the vegetation is actually quite effective at trapping particulate matter. We know that because of scientific research.

        2. Howard P

          Your air quality measurement guy is neither an epidemiologist, nor a physician.  He’s a very competent air quality measurement guy.  Nothing more, nothing less…

          You, by contrast, are none of the above…

        3. Ron

          David: Sounds like someone desperately wants to settle this issue on a blog. You’re also assuming that I have some type of argument to make, other than what I’ve noted.

        4. Tia Will

          Ron

          It is quite possible for Dr. Cahill to be correct about the measurements he has done, and for Dr. Salocks to be correct about the toxicologic effects, and for Don Shor to be correct about the mitigation effects of plantings, and for the epidemiologist to be correct about the lack of increased respiratory illnesses along this portion of the I-80 corridor, and for my perinatologist consultant to be correct about the lack of evidence for fetal endangerment. There are many factors to be considered and it is my point that all should be weighed. This is a decision based on all of the pros and cons of the project and should not devolve to cheerleading for one’s preferred expert to support one’s own bias.

        5. Ron

          Tia:  I understand that it involves multiple disciplines, and that these disciplines would be referenced in the event of a comprehensive study (which has been recommended, but not completed).

          The first step would belong to someone like Dr. Cahill, not Dr. Salocks.

          From what I’ve seen, there’s an effort to downplay the initial warnings and recommendations, from Dr. Cahill.

          Regarding the effectiveness of mitigations, the first step is to understand what’s actually there. Beyond that, I’m not sure who has the necessary expertise to determine possible effectiveness. (But, I suspect that it would be someone with a scientific background. Perhaps Dr. Cahill, again.)

          Again, a political blog is not the best way to conduct science.

          1. Don Shor

            The air quality at the site was studied in 2015 on a site that “was analogous to the middle of the property and therefore should provide comparable results” by an associate of Dr. Cahill’s.
            Mitigation strategies are based on published research, including work by Dr. Cahill and others. The efficacy of vegetative barriers is now accepted as a recommended strategy by the EPA (2016) and the Air Resources Board (April 2017) which are agencies staffed by regulatory scientists who specifically have “the necessary expertise to determine possible effectiveness.”
            Science is “conducted” via published peer-reviewed studies, which are then interpreted by others who use them in their areas of expertise. That is precisely what is happening as agencies assess vegetative barriers and also as they are implemented.

        6. David Greenwald

          “The first step would belong to someone like Dr. Cahill, not Dr. Salocks.”

          That statement has no basis, it’s simply your opinion.

          And again, the election will be decided by the voters, not in a scientific journal, so your repeated end comment also has no basis.

        7. Ron

          Air quality measurements/studies would absolutely/normally be done by someone like Dr. Cahill, and not Dr. Salocks.

          That is not my “opinion”. It is a fact, based upon the differences between their respective fields. They are not interchangeable.

    2. Aaron Latta

      “As previously noted, the “do nothing” alternative is not the only other choice.  For example, there is an adjacent 5,300 acre land-mass that already includes some student housing, and which could house more.”

      Ron: I agree that the university should build more but to describe asking the university for more housing as a viable third option to our crisis is not sound. As of right now there is very little guarantee that meeting with university officials will result in greater on campus housing. In effect your third option just becomes the “do nothing” with the added benefit of getting a nice video of all of us yelling at administrators (fun but not useful). Working on the administration will take time and if we dont take action in the city this crisis will only hurt more people and get more expensive. Nishi is the best student housing proposal I have seen so far and the lengths to which the developer met the student and non-student concerns is far beyond what I would have predicted several months ago. Using the university as the target of our ire is the “do nothing” option in disguise.

    3. Richard McCann

      Again, I will repeat this–most of that 5,300 acres is devoted to agricultural research that improves productivity for feeding 7 billion people. Only a small portion is available for housing, and one of the prime sites identified on Old Davis Road has exactly the same air quality issues.

      1. Ron

        Richard:  “Only a small portion is available for housing, and one of the prime sites identified on Old Davis Road has exactly the same air quality issues.”

        I have not seen any evidence to support either of these statements.

         

  4. Todd Edelman

    In regards to:

    The building design incorporates a state-of-the-art indoor air filtration system (MERV 13) that will eliminate most of the airborne particles.

    The issue is not just airborne particles, but – and it is explicit in the EIR addendum – ultrafine particles (UFPs) 1.0 micron or smaller in size. MERV 13 filters remove only 70% or less of these. See here. Is Dr. Salocks saying that most is “95%”, which is the goal mentioned in the EIR update? (As I understand i, MERV 13 filters are also meant to be used at Lincoln40 – so is all they are doing at Nishi in regards to interior mitigation?)

    In regards to: 

     A 100-foot-wide continuous urban forest with plant selections based on filtering qualities applicable to fine particulate matter will be planted between I-80 and the Nishi site.

    If this width of trees and shrubbery is so effective, why not make it twice as wide by eliminating the outside parking lots? Are the cars of 700 persons more important than the health of thousands (Nishi residents, plus Solano Park residents who are indicated as benefiting from this measure.)?

    Additionally, in the EIR addendum (4-11) “… non-residential structures serve as a barrier between I-80 and the residential buildings” seems to say that these structures are an intended measure for mitigation. But the current Nishi plan does not have buildings at this location, only parking lots (with some trees).

     

     

     

  5. Tia Will

    Ron

    The first step would belong to someone like Dr. Cahill, not Dr. Salocks.”

    Ok, and Dr. Cahill has already weighed in. Dr. Salocks has responded. I responded with the perinatology and epidemiology information once that was available at the time of Nishi 1. I am not sure what your point was since this seems like the correct order of operations to me.

    From what I’ve seen, there’s an effort to downplay the initial warnings and recommendations, from Dr. Cahill.”

    I do not see how you think that Dr. Cahill’s concerns were downplayed. I reviewed his study with an expert in statistics ( as well as the statistics from the other articles that had been referenced), with a public health expert, with an epidemiologist, and a perinatologist. No one brushed this off. All evaluated the material from their area of expertise before I weighed in with their opinions.

    Again, a political blog is not the best way to conduct science”

    Again, no one is conducting science here. What is being done is to present evidence that we have gathered from a number of sources so that others who may not have ready access to these sources of expertise can read and form their own opinion. That certainly is an appropriate project for a political blog.

    1. Ron

      Tia:  “Ok, and Dr. Cahill has already weighed in.”

      He has, and has recommended that a complete study be conducted on-site.

      Tia:  “Again, no one is conducting science here.”

      I would agree that no one is conducting science, here.  However, there is an attempt to portray it as such.

      The missing “elephant in the room” regarding the discussion on this blog is Dr. Cahill, himself.  We’re only hearing one-sided air quality arguments from those who otherwise support the project, at this point.

      I don’t pretend to know the answers, here.  Other than what I’ve noted, regarding the one-sided nature of the arguments put forth. (And, the fact that only one guy that we’re aware of is actually qualified to conduct air quality studies, regarding the participants on this blog.)

       

       

       

      1. David Greenwald

        “He has, and has recommended that a complete study be conducted on-site.”

        He’s entitled to his opinion.  Not everyone agrees it’s necessary.   I for one do not see what we gain by it unless it can be established that there is a level of particulate matter in the air that Would trigger a different level of concern and a different course of action. Thus far I have one person has offered were at such a level would look like and that includes Dr. Cahill

        1. Ron

          Well, we already know that the initial study indicated that the results exceed existing standards.  Some believe that they know enough to discount that fact.  If that’s the case, perhaps supporters of the proposal should put forth some numbers that would generate sufficient concern, from their point of view.

        2. Ron

          Probably another question for Dr. Cahill.  If I recall correctly, he’s since cited some other concerns regarding the rail line, for example. But again, you’re arguing with someone (me) who hasn’t paid extremely close attention to this issue, with a “goal” of discounting the results.

          In all honesty, I have other concerns regarding the proposal (which have nothing to do with air quality). I’ve probably paid more attention to those.

          But again (since you’re proposing to disregard existing standards), at what point would you agree that the problem is too great?

        3. David Greenwald

          This is the question I have posed that I have not gotten a suitable answer to: at what level of particulate matter would it represent a considerable health risk at one to three years of exposure?

  6. Tia Will

    However, there is an attempt to portray it as such.”

    I do not see anyone who is attempting to portray their contributions as “scientific research” with the exception of Dr. Cahill’s original study. Everyone else has presented either a commentary on what his findings might or might not mean, whether they reach statistical significance, or whether there are over riding or mitigating factors. Who do you believe has attempted to imply that the evidence they are citing represents research? Please be specific.

    1. Ron

      Well, there’s the quote below (from the 2nd pargaragph, in the article, above).  Followed by direct challenges to the conclusions that Dr. Cahill made regarding wind patterns, site characteristics, comparisons with other sites, the effectiveness of mitigation efforts, etc.  Virtually the entire article, and most of the comments that followed (from obvious supporters of the proposal).  (Including topics that Dr. Cahill has the most expertise in.) 

      If you can’t see this as plain as day, I don’t know what else to say.

      From article:  “There is no scientific basis for concluding that air quality at the Nishi site, as influenced by freeway traffic, is any different than at other residential locations, existing and proposed, along the Interstate 80 corridor in Davis.”

       

      1. David Greenwald

        The wind patterns have been established by metereological data.  A lot of Cahill’s analysis appears questionable based on what has been presented here by Salocks as well as Don and Larry Greene. I know you believe Cahill is an expert on everything, but other people can read data too.

        1. Ron

          I believe that you’re referring to the wind patterns at the airport. Not sure if they’re exactly the same on the site, nor am I sure if that makes much difference, regarding your arguments.

          Other than that, I’m not going to engage with you (or anyone else) regarding your arguments.  I’ve read them (repeatedly), but have no response. There’s nothing “wrong” with presenting such arguments, but they have not been scientifically vetted or reviewed. They are, in fact, political arguments at this point. And, you and I are not qualified to engage regarding the science, one way or another.

          I am not actually taking a position here, other than what I’ve noted.  It appears that you’re looking for someone to argue with.  Again, the person you should engage is Dr. Cahill, not me.

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