June 30, 2025, Planning Board Special Meeting Transcript - WEHI

08/07/2025 02:56:42 PM Page 37 to 40 of 175 10 of 70 sheets 37 rephrase the question.1 THE PUBLIC: So what are the potential risks2 when the slope becomes destabilized?3 THE WITNESS: Well, I have not been involved4 in a rock mass basalt that has become destabilized as a5 result of blasting. So it's hard for me to speculate on6 what would happen. But as I have testified and provided7 that the safeguards are in place, that is a controlled8 blasting program is in place, I'm not expecting there --9 that risk becomes incredibly low, if not all together10 zero with the indication of controlled blasting11 techniques. So then as the amount of charge is put in12 the hole and blasted the energy is reduced and if there13 is an air cushion between, let's say the face of the14 excavation and down slope, then there's no -- the risk15 is mitigated by that method.16 THE PUBLIC: Okay.17 You talked a little bit about -- you said18 you found Preakness Basalt, hard rock, but I did a19 little research, I mean, I'm not a, you know, geologist20 but Preakness Basalt stores a lot of natural geological21 stress to begin with, correct?22 THE WITNESS: Certainly at a depth --23 MR. AFRAN: Mr. Seel.24 THE WITNESS: Oh, I'm sorry. So when rock25 38 is exposed to the ground surface it tends to dilate1 slightly, especially on the lead face. There's a2 certain amount of findings that exist in the rock mass,3 especially with the depth with burial, the depth of good4 rock and the face very gradually starts to de-stress and5 open up. So the -- so materials, they were, the6 materials you see today are what we would expect to see7 after blasting, provided those controlled techniques are8 put in place.9 THE PUBLIC: So considering if blasting was10 to be done correctly, properly, according to ordinances,11 all those other things, laws, etc., couldn't blasting12 trigger release of some of that stress causing13 unexpected cracking, more mass movement?14 THE WITNESS: I'm struggling to find a case15 where I've seen something like that happen. You're16 talking about stress fields in rock, you're talking17 about large scale stresses, these are relatively smaller18 that we're seeing in outcrops and I would expect that,19 I've not seen where uncontrolled blasting has been done20 in an instance relative to neighboring homes. In one21 instance I've seen where it was used in a quarry and if22 it does, it can

xpect that,19 I've not seen where uncontrolled blasting has been done20 in an instance relative to neighboring homes. In one21 instance I've seen where it was used in a quarry and if22 it does, it can be destructive, but that was -- those23 cases are very -- they're not relative to what we're24 seeing or what we expect to see here in a development in25 39 a residential area.1 THE PUBLIC: Do you know if this slope2 contains subsurface water channels?3 THE WITNESS: Well, we look for ground4 water.5 THE PUBLIC: I guess how far would you have6 to go to see or know if there was subsurface water? I7 mean, could it be if you went down, what, 20-feet?8 THE WITNESS: 20 or 40 feet.9 THE PUBLIC: 20 or 40. Okay.10 So in your professional opinion blasting on11 or above Preakness Basalt ridge line is, is it risky?12 One being low and ten being high on a scale of one to13 ten.14 MR. PLOCKER: I'm going to object.15 CHAIRMAN BAGOFF: Sir, he hasn't testified16 anything about this.17 THE PUBLIC: About what?18 CHAIRMAN BAGOFF: We're going too far off19 the hypotheticals.20 THE PUBLIC: Okay.21 CHAIRMAN BAGOFF: It's just a different22 flavor vanilla.23 THE PUBLIC: Well, I was asking for a24 professional opinion for blasting on, which we're25 40 building on Preakness Basalt.1 CHAIRMAN BAGOFF: You asked for the risks.2 THE PUBLIC: Okay.3 CHAIRMAN BAGOFF: But move on.4 THE PUBLIC: Okay.5 Will your firm be assisting on the blasting6 guidelines or is this just specifically for, I guess I7 have to ask something that you testified on, I8 apologize.9 I think I'm okay for now.10 CHAIRMAN BAGOFF: Would any other member of11 the public have any questions for Mr. Seel on his12 testimony? Please come up and state your name for the13 record.14 THE PUBLIC: Yes, hello. My name is Leigh15 Masci. I have a question for Mr. Seel.16 MS. McGOVERN: Did you say Clair?17 THE PUBLIC: Leigh.18 MS. McGOVERN: Leigh.19 THE PUBLIC: Yes.20 Mr. Seel, in your professional opinion what21 do you think might be some of the effects of blasting on22 the walls of the houses closest to and directly across23 from this site?24 MR. PLOCKER: Again, this wasn't in his25