Pier Park Redeux

We got a little more info the last two weeks on the ongoing non-story of Pier Park contamination, and each little bit of info we get fills a few more gaps. I have to throw out the standard caveat here: although I have spent most of the last decade working on contaminated sites investigation and management in one capacity or another, I do not have the technical knowledge about this site to offer any “professional” opinions on it. Everything I know about this site is from the Council Reports and stories in the local media. So the following is a personal opinion based on incomplete knowledge, so treat it for what it is worth (approximately equal to what you paid for it).

So far we have had the February 14 update report to Council, and in March Chris Bell gave a delegation to Council raising his concerns about the ongoing remediation at the park, and we have seen an update on the Park and an interview with the project manager in the local papers.

First the update. It seems the (presumably shallow) soils have been remediated, and there is ongoing progress on the scrap metal “mounds”. The groundwater contamination plume (I will avoid the pejorative “toxic blob”) has been delineated (which means they have drilled holes all around it, sampled all of those wells, and found them clean), so they can now definitively say where the contamination is and where it is not. It is all within a 350 m^2 area, and they are between 40 and 50 feet below the surface. The highest concentrations are on the adjacent property, and if the groundwater flows towards the river (a safe assumption at that depth), then we can say the chlorinated solvents came from the adjacent property and migrated on to the Park Site through groundwater flow.

It is pretty clear the presence of these “DNAPL” chlorinated solvents was a surprise. It is extremely unlikely that this plume would have been discovered in any “Stage 1” or “Stage 2” Preliminary Site Investigation of the site, the type of investigation one would do prior to purchasing or developing such a site. From what I can interpret from the available reports, they bumped into this stuff while trying to do some depth-delineation of known contamination on the site. Such is the nature of the Contaminated Sites Regulations, though, that they have found it, they need to deal with it in order to get a certificate from the Ministry of Environment for the site.

These are liquid hydrocarbon solvents (likely carbon tetrachloride or tetrachloroethylene or the sort) that are heavier than water, so they sink to the bottom of the groundwater column in which they are dumped (much like the vinegar in your salad dressing drops down below the olive oil). This stuff is toxic to the environment, and potentially harmful to people, yes. Most chlorinated solvents are an irritant in low concentrations, harmful to organs like the brain to the liver in higher concentrations, and potentially carcinogenic with long-term exposure, kind of like the stuff you put in your gas tank every day or the polycyclic aromatic hydrocarbon smog you are exposed to walking through cosmetics section of the Bay. Toxic, but not the worst thing known to man. You can walk into Canadian tire and purchase Tetrochloroethylene for cleaning your brakes, and prior to the Montreal Protocol, you could buy Carbon Tetrachloride for everything from killing ants to running your refrigerator (but we called it Freon when using it for the latter). Mostly, they are common drycleaning chemicals.

Honestly, I cannot comment on the budget part of the update, as I am not up to speed on the budget history of this site. It is possible that this DNAPL plume is going to expand the budget of the park, but Jim Lowrie assures us it is within the “contingency” budget. Before we start yelling boondoggle, remember two things: this DNAPL was almost certainly unexpected and unpredictable, and that is what contingency budgets are for: contingent on the unexpected happening. Second, this extra cost is potentially 100% recoverable from whoever owns the property that is the source of the contamination. At this point, the concerned taxpayer would say “well, then make them clean it up!” Unfortunately, there is no way under the Contaminated Sites Regulations that the City or anyone else can force the owner of the source property to clean up the City’s property. What the City can do is clean it up, and then send the bill to the owner of the source property. They have to do it through the civil courts, but if managing this DNAPL really costs the City $1 million as some have suggested, and we can prove it came from off-site, then it should be pretty simple to recover those costs. But first, the City actually has to spend the money before it can ask for compensation. You may not like that, but it is Provincial law.

Now onto Mr. Bell’s concerns. I have met with Mr. Bell and discussed this issue with him. I respect him for his concern for the community, his persistence, and for speaking out about an issue that is relevant to all of us in the City. Just by asking questions publicly and making sure this issue stays in front of mind (if not on the front page of the Record), he is providing more impetus to the City and their consultants to make sure their “i”s are dotted and the “t”s are crossed, and to make sure the public is kept updated on what is happening down there (remember, all of these reports will be public information eventually, so the City has nothing to lose by sharing them with us). That said, just because Chris is constantly asking questions doesn’t mean the answers are not adequate.

You can hear his delegation to council here (he starts about 1:03 in and the conversation goes on for about 15 minutes).

First, it seemed a bit flippant by Mr. Lowrie, but Madame Railjogger is almost certainly much more endangered by trains and car/truck exhaust jogging along Front Street than from vapours from the DNAPL plume. My guess based on how they are managing this plume (barrier wall), is that the surface vapours will be “risk assessed”, and the City is confident the Ministry will agree there is no unacceptable risk. With all hydrocarbons, there are separate standards for vapours rising up through the soils, based on the potential health effects of people breathing those vapours. In this case, the amount of vapour produced at depth will be small, but not negligible. However, those vapours will have to rise up through a significant saturated water column, maybe 35 feet thick, then through another 15 feet of unsaturated soils before reaching the surface, all along the way being both degraded and diluted. By the time these vapours hit the surface where Madame Railjogger is working out, they are likely to be diluted to non-detectable levels. However, even if this was not the case, the park will not be getting a certificate from the Ministry of Environment until that potential pathway is assessed. If there are vapours getting to the surface, then they will be required to put a barrier in place, but in this case, that looks pretty unlikely.

Second, my turn to be flippant: Just because Mr. Bell and the Mayor don’t understand hydrogeology, it doesn’t mean no-one else does. These contaminants are heavier than water; when dropped in a column of water, they sink. I’m not sure what Mr. Bell is calling “hardpan”, but New Westminster is underlain by permeable and semi-permeable materials for tens of metres, or more. DNAPL, when dropped in the groundwater, will go down until it hits a layer of sediment that is not permeable, then it will stay there (vertically), while spreading out on the impermeable surface, and even flow downhill along that surface if there is a slope or a groundwater flow to push it along. The Spring floods (freshet) will never cause the contaminants to rise to the surface, like they would if this was LNAPL (that is, hydrocarbons lighter than water). Placing a u-shaped barrier (described by Mr. Bell as a “fish weir”) may work perfectly fine to stop the flow of the contaminants downhill (i.e. towards the River), as long as the DNAPL cannot flow under the wall, build up to sufficient thickness to flow over the wall, or have a reason to change flow direction and go around the wall. Bentonite / concrete walls l are extremely effective, and have been used for dozens of years, in thousands of applications; the technology is well understood, effective, and reliable. Assuming there is good hydrogeology behind it, it should be the best solution here. The only pathway to people or the environment is to go sideways into the river bottom, then leak out into the river. The barrier wall will stop this from happening. The plume won’t go anywhere, it will be kept stable in place where it can do no harm. Eventually (over many, many decades I suspect) it will dissolve away, biodegrade, and otherwise break down, but no active measures will be taken to physically remove the stuff.

Third: with the contamination ‘contained’, is it a threat to the park, my puppy, my kids? Simple answer is no. This stuff is stable and is a long way down. Your child will not be able to touch this stuff, drink water contaminated with it, or breathe vapours coming off of it. With a barrier wall, this stuff will not migrate to river sediment and get into the food chain of the Pacific Salmon. There is no reasonable way that this stuff is going to get to your kid’s system. Since there will be residual contamination on the site, there will need to be a Human Health Risk Assessment demonstrating that this residual material poses no health risks prior to the City getting a certificate for the park from the Province. With the Risk managed, there is no reason people cannot live, work and play on top of a contained DNAPL plume with no risk to their health.

And that is a significant point; the Province is overseeing this work. The City and their Contractor don’t need to reassure me to move forward, nor do they have to convince Mr. Bell that everything is on the up-and-up. They need to convince the Ministry of Environment. Mr. Bell mentions in his delegation that he trusts the MoE to provide oversight, and that is what he is getting. The MoE will not issue a certificate for the Park unless they are convinced from the science on the ground that there is no risk to human health or the environment. I don’t know what else to ask for from the environmental side.

So, in summary, I remain unconcerned about the contamination issue in the Pier Park. If Mr. Bell wants to continue to make an issue of this, he might be better served chasing down the cost overrun issue, or the process for public consultation around the spending. I’m not an accountant, I don’t know much about that side of the thing, so I am best to avoid that (go to moneynewwest.blogspot.com, maybe they can help). Also, as a taxpayers, I hope the people making decisions for the City are motivated to try to recover as much of the contamination mitigation costs from the railway or whomever caused the DNAPL plume in the first place. Keep in mind 100% of this money should be recoverable from the “persons responsible” for the contamination, or the landowner from whom we received this contamination, if the City chooses to pursue those costs. I think it is important that our tax dollars not be used to clean up someone else’s spill incident, if that someone else is still around to pay for the cleanup. That is where I am looking for fiscal responsibility on this one.

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