Lead Contamination in Soil: A Scientific Analysis of a Boat Keel Pour

[00:00:02]so we went to a friend's house uh for the Super Bowl and we were talking about doing the lead poor video it was right after that and all of the comments we got about us dying of blood poisoning and poisoning the Earth and all the terrible things that we've done by doing this um and party was Sarah here who's a friend of ours and she started giving us all of the scientific information about lead that we did not know and she was kind enough to come in and share some of that knowledge with us so without further Ado I'm going to turn it over to Sarah my name is Sarah I'm a graduate student at the University of Massachusetts Amherst where I'm studying landscape architecture and so in order to design the most sustainable and ecologically friendly Landscapes I've been studying phyto remediation which is how plants can take up contaminants from the soil I want to know how the water moves through the landscape and what plants could be used to remove contaminants from heavily contaminated sites so lead is problematic in that regard lead when it's in soil binds really really tightly to soil particles and it's very very hard once those bonds have been made for the lead to actually get into water so once lead's in the soil it mostly stays there which is why uh when uh Steve and Alex were at the Super Bowl party and mentioned that people were concerned about lead contamination I mentioned uh I had been studying lead and how we could remediate it uh remove it from heavily contaminated sites with plants and how that's actually very problematic lead once it's in the soil stays in the soil in order to provide a little bit of context for my claims uh I've researched uh some general standards in the state of Massachusetts the Massachusetts executive office of energy and environmental Affairs developed the Massachusetts contingency plan numerical standards these are standards of how much lead you could have in soil or water before it's problematic and needs to be remediated in some capacity the levels for groundwater are very very low it takes only a little tiny bit of lead to be contaminated in water before you have a problem so that would be about 15 parts per billion which is a very very small amount however it's extremely difficult for lead to get into water the reason why lead poisoning uh and contamin ated water has become prevalent uh and kind of a health scare in the nation is because old lead pipes were used for water so you'd have lead pipes bringing water to people's homes for drinking water all the time multiple times a day every day for years and years and years and the lead would accumulate and then you could get lead poisoning on the other hand when you have lead contamination in soil the lead binds so tightly to soil particles that the standards for the mCP soil standards are much much higher so instead of the 15 parts per billion allowable before you have problematic lead levels in water the levels for soil contamination are 200 parts per million if it was an active landscape where you're having a schoolyard where small children might be present or uh agricultural use for a a residential yard the allowable levels of lead contamination are 600 parts per million so many orders of magnitude larger than what's allowable for water and the reason that is is because lead binds so tightly to phosphates iron oxides and clay soil particles that once it gets into soil it stays there however in order for plants to uptake nutrients it has to be soluble nutrients have to be dissolved in water it's really the water that plants uptake in order to get the nutrients that they need that's why lead is so hard to clean up from a site in order to actually get it into plants when you want to get it into plants you have to use uh chemical keator which you add to the soil to break the bonds between phosphates iron oxides clay all the the um nutrients you have in the soil particles that the lead binds so tightly to unless you actively apply key laters the lead is going to stay in the soil so lead will not be taken up by plants so it won't be present in any plant matter that grows there whether it's meant for human consumption or not there is a lower level allowed for specific uses just to be an extra precaution and because there could be uh lead dust or contaminants in the top layers of soil that might physically get onto food so if the food isn't being very carefully washed or if you have small children playing in the very top levels of heavily contaminated dirt that is problematic however in the situation that we have here where they had a pour of lead into a wooden mold that was buried in soil very very little amount of that lead is actually going to come in contact with the soil and if it did it would bind very tightly to those particles and then stay there because I'm a graduate student at UMass uh I have available the center for agriculture food and the environment which is an Outreach extension of UMass that actually Prov provides soil testing so for a small fee anyone including the guys here Acorn to Arabella can provide a soil sample and have it tested at the UMass labs in order to see levels of various contaminants or heavy metals in this case in their soil so we can uh dig the soil samples around the POR site because we're testing for heavy metals it's actually going to be a series of 12 subsamples that are dug at a depth of 6 to 8 in and then mixed in a bucket and one cup of that soil can then be brought to the UMass Labs where they'll be tested for all the different heavy metal contaminants we can compare that to the mCP standards and see how this lead pore has impacted the soils here so thank you Sarah for coming and sharing some of your knowledge and we're going to go outside here in a minute and get some soil samples and Sarah will take those and we'll find out exactly how much lead we put into the soil here um but before we do that let's talk a little bit about my blood so there's a lot of concern about our blood level with lead throughout this pore cuz lead you can inhale it you can eat it you can absorb it through your skin and it is toxic um so I had the most contact with the lead throughout this entire process I was the one that collected the wheel weights and dumped them into the tank and was inside the melting tank stacking the lead I was the one that was the closest to the poe keeping an eye on everything while everyone else was far up wind and Away um I did have a respirator on but I do have a beard so the respirator doesn't get as good of fit as it you know would be ideal so I went and got tested figuring that since I have been exposed to way more lead than anyone else in this process that if I was good we could reasonably assume that everyone else was so I sent a sample of blood in and I got the test and what we found out was that I have seven microgram per deciliter in my blood which works out to about 70 parts per billion and for a reference uh in water they make it so you don't want to have more than 15 parts per billion so if my blood were drinking water it would be kind of problematic but for an adult seven is no big deal um the US Department of Health and Human Services recommends that adults keep their blood level below 10 micrograms per deciliter so I'm fine there and they don't believe that symptoms occur till over 40 so there have a long long way to go before we could even become symptomatic and they don't do anything about it any sort of therapy usually until it's over 50 which we have a long way to go the reason that they are so stringent with water is that if you're a little kid and you're drinking the water every day and you're bathing in the water every day you can get lead and it'll start to build up in your system and it affects kids a lot lot worse than it affects adults so if you ingest lead it ends up getting into your blood and it kicks around in your blood for maybe 40 days or less and then after that it gets stored in your teeth and your bones and it's a lot harder to get rid of so if you're a little kid and your bones are developed veloping and you have this access to the lead that's in your drinking water it really does become a big problem and that's where we see all these issues with the lead poisoning for an adult 7 G micrograms per deciliter is well within the allowable amount and should pose no problems to me whatsoever down the road and everyone else who is at the port or in the general vicinity area should also be completely safe all right should we get some soil samples yeah let's do it all right other way boom perfect great okay here's shovel I'll let you do this you're the expert we buried the lead in there and then we moved it over here and we did a bunch of shaping over here so you bury the lead in here in here yep and we'll have to we all have to go outside and get access to the other part yeah the lead heel came to about here it's all buried in here and then we moved it out here here and we did a bunch of flattening and shaping so you might want to check the soil in here as well okay so this fill in where was that from uh some of that was from in the hole some of that was from around the hole all right that's some wood was that part of the mold no it was just some wood that was buried in there okay like we said this was the site there used to be a big old barn here that's uh burnt down long time ago and then they just doze the rest of it over so Lord only knows what's buried down there we took a bunch of subsamples which is meant to be representative of the entire site that we're looking to to measure here contamination doesn't occur evenly it occurs in some areas there will be hot spots other areas will have significantly less contamination so by sampling multiple sites through around the area that we're looking at we can and then mix them together taking our sample from this that's going to give us a better representation understanding of the actual contamination that's gone on first off big thanks to Sarah for coming and sharing your knowledge with us about lead and its remediation and the results came in finally took a couple weeks for yourass to do all the soil samples but we got the results and they look pretty good the lead level uh the heavy metal thresholds set by the US CPA are 400 mg per kog in the soil so 400 and from our soil samples we came up with 46.9 so we are well below the threshold for lead and where we did the POR is actually the site of an old barn there used to be a huge three-story Barn here that stood for a very long time and it was taken down before I was born um but just the I'm sure that that was painted in lead paint at some point and that alone would be more than enough to get us values of 46.9 and then same thing with nickel cadum chromium zinc and copper we are all well well below what the uh thresholds are set by the US EPA so it doesn't seem like we only did any real significant damage to ourselves or to the soil or to the neighbors so although lead is certainly dangerous and it definitely is toxic and it's something to be careful of uh it's not as bad as a lot of people think and we did not poison ourselves or the entire town before we wrap this up we want to put out a little Call to Arms and we could use your help so we have a lot of great timber for the boat but there's one species of New England Timber that we would really like to get our mits on and we can't really get it from a saw and it's this wood called black locust uh it grows native around here especially along the river so if you're anywhere near the Connecticut River there's a good chance you have some around we're looking for a black locust tree or six that are about y big around so if you walk up to them and at chest Tite give them a hug and your hands just meet or don't quite meet that's an awesome siiz Locus and that is what we are looking for uh our offer is to come to your home to take your Locust and we can clean up the mess so I can borrow my friend Tom's equipment we can show up with the dump truck and the chipper we can cut down the tree we can chip all the brush and take it away and I can even come back with the stump grinder and leave you with nothing but a bare patch of Earth so if you got some Locust and you'd like to get rid of it we would love to take it and love to incorporate it into Arabella uh so we're going to put in a little link here with some info so that you can identify black locust uh it's very important that it's black Locus and not honey Locus but if you have some and if you're willing to part with it we would love to hear from you and the other thing is you need to be within a one hour drive of us in grany Massachusetts so the ZIP code is 01033 please throw that into Google Maps or whatever you want to use and make sure that you're within an hour but if you're within an hour of us and you have some decent sized locusts we really really would love to hear from you