August 13 2025, Planning Board Special Meeting Transcript - WEHI

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 11 MS. McGOVERN: I don't have a copy of it. I got to see it and I handed it back. It's going to the township attorney. MR. AFRAN: Okay. I'll get a copy of it then. MS. McGOVERN: At some point, yes. MR. AFRAN: So Mr. Gaff is here obviously and I have some proffers to make, but I think that should be done after his testimony. CHAIRMAN BAGOFF: Go right ahead, sir. MR. AFRAN: Mr. Goll, excuse me. MS. MCGOVERN: And the next number on our exhibits are 21. MR. AFRAN: Mr. Goll has already been sworn, I assume he continues to remain under oath. MS. MCGOVERN: You understand you are still under oath? THE WITNESS: I do. MS. MCGOVERN: Okay. MR. AFRAN: I'm going to allow Mr. Goll to just present his report. I may interject questions at some point. I assume he's prepared to do that. THE WITNESS: Yes. MR. AFRAN: Thank you. THE WITNESS: The last time I was here I

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 12 testified -- thank you for waiting for me. I appreciate it. MR. AFRAN: Try to be close to the mic. THE WITNESS: The last time I was here -- CHAIRMAN BAGOFF: Excuse me one second. I'm going to ask members of the public, if you can't hear just raise your hand. Okay. So he's going to talk loud and if you can't hear just raise your hand, I will identify you and I will know. Do me a favor, go to the town council meeting and please express to them that you can't hear during the Planning Board meetings. Okay. Go right ahead, sir. THE WITNESS: Thank you. The last time I was here I testified on a report from July that I prepared reviewing the geotechnical slope stability analysis in the area of Building D. The question was asked that, I apologize to the member of the board, one of the board members herself, my answer was I just -- I didn't have time but also I thought the applicant might do that as well. But what I did is I just ended up running the numbers myself. So what we did is we took two, two of the cross sections using the applicants data or the applicants engineers data and used their borings and if you recall

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 13 the last meeting that I was here, I stated that they used the best data that they found. In other words, the most confident rock subsurface conditions in all their cross sections. There was a -- some of their borings they got, for example, very low RQDs, if you can remember that. The rock quality designation. The lower -- it's from zero to 100 percent and the lower the quality, in other words, the lower the percentage, the worse the rock quality was in. And we're using the higher rock quality data that they had and assuming they're very high, what's called a geological strength index, which is also reflective of, you can use that during the RQDs you get in the field. So for cross section C and D -- cross section C is the section that is the most northeast of the property. It's actually the section that goes through and then it goes down Howell Avenue. It's where the closest houses are -- excuse me, on Howell Drive, are located. And we also looked at Section D, which is just next to that, just a little bit more south of that in the same vicinity of that slope. So we ended up using their information to develop our slope stability analysis. So we obtained topographic data from the town that's available, the township wide topographic data because I did not have access to the applicants

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 14 topographic information and CAD. We reviewed it, it was essentially the same as we would expect it to be and then we input that into the geometry of the slopes and then took the boring data that they provided in those locations and entered them into the program, to make sure that we were running a similar model or a similar analysis. We simply just accepted on our first run, based on our geometry, just to sort of like a test to make sure that we're kind of talking the same language in terms of the analysis. We put their same exact parameters in. And so for example, on Figure 1 that you might look at, we got a factor of safety 1.589 in the worst case scenario and they had a factor of safety of 1.599. For all intents and purposes that's the same, that's for Section C. And then for Section D similar analysis. We came up with a factor of safety of 1.936 and they came -- they had developed a factor of safety of 1.938. That's assuming, again, we're using their data. And we're just using that to corroborate our -- the layout of our model to make sure it's the same. MR. PLOCKER: I'm going to object just for the record. It looks like the notation, the caption at the bottom of the exhibit, it looks like it's reversed. It says that Langan was on top and Princeton Hydro is on

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 15 the bottom. I think the testimony just reflected the opposite. So just so the record is clear can we get some clarification. MR. AFRAN: Let's ask the witness then to explain. Mr. Plocker's suggesting that on Page 2 of your report, right Mr. Plocker? MR. PLOCKER: Two and three. MR. AFRAN: Two and three that it may be, Mr. Plocker thinks from what you said, that the Langan version versus your version, Princeton Hydro's version, may be transposed. THE WITNESS: Could you read back what I said, if possible. MR. AFRAN: We would not object, there's a court reporter present. CHAIRMAN BAGOFF: I don't know. THE WITNESS: Let me just -- CHAIRMAN BAGOFF: I'll tell you what. I'll tell you what, for clarity look at your diagram and read the diagram into the record so it's clear. MR. AFRAN: We can also -- Mr. Chairman -- MS. McGOVERN: From top to bottom. CHAIRMAN BAGOFF: From top to bottom. MR. AFRAN: Mr. Chairman, we do have it available on the screen, if that's available.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 16 CHAIRMAN BAGOFF: I know. Let him read it from it and say, this is yours or it's theirs. And if from the bottom it's either yours or it's theirs. THE WITNESS: On Figure 1 the Langan model is on the top and the Princeton Hydro model is on the bottom. That is correct. They both reflect that. If I had misspoke and reversed that I apologize but that's -- CHAIRMAN BAGOFF: Thank you. THE WITNESS: Regardless it makes no difference because we basically replicated their model and we came up with the same number because we used their parameters that they assumed based on test rock information. And the same thing on Page 3. We also came up with similar factors of safety regarding the model. Ours -- theirs was on top and ours was on the bottom. So we came up with a factor of safety of 1.938 and they came factor of safety of 1.36. So I thank you for that correction if I had reversed that. MR. AFRAN: Mr. Goll, I have a couple quick questions for you. When you said the numbers were basically the same, you're referring on Page 2 of your report to the fact that the Langan number was 1.589 and yours was 1.599, is that correct?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 17 THE WITNESS: The Langan's number is 1.589 and our number was 1.599. MR. AFRAN: Right. When you said it didn't make that much difference, is that because those numbers were close? THE WITNESS: Yeah, they're very close. MR. AFRAN: Okay. And the same applies to Page 3? THE WITNESS: Yes. Yes. I mean, we're down to a hundredth of numbers, so it's not -- in this analysis not, it's not a big deal. MR. AFRAN: Thank you. Please continue. A. Yes. So we did that same thing on Figure 2, Langan's analysis on the top, this is basically a screen shot from their report, and ours is a screen shot from our analysis at the bottom. So one of the things we then wanted to do, we did a sensitivity analysis using GSI and modifying that and came up with, looking at what happens when you change the GSI, which is geological strength index and reflective of the poor -- and the very poor joint condition. And so we looked at a ten-foot thick layer of bedrock with eager parameters that we changed because that was more reflective of the borings that were

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 18 prepared for this -- that were obtained by Langan on this project. So there was ten-feet of rock boring as well and we used that. That quality of that, that low quality, if you recall, I think it was C had a rock quality data of zero and 23 -- 0 percent and 23 percent of 100. And so we need to take that GSI number and lower it to an appropriate number. And so that's what we did. So we took a number on the Section C and ended up changing the GSI to 20 and our lowest numbers -- well, there's an isolated number there that frankly you can disregard, it's point 774 on Figure 3 on the bottom right. That's actually less than one. The slope is actually failing, but it's a very small area down slope and that, even if it is failing that's what it is in that location. It's very isolated. However, when you go up to the other cross sections and looking for the lowest factor of safety, the number on cross section C drops from a 1. -- drops from a 1.589 and 1.599 down to a 1.48. So that dropped as well. But more significantly if you go to Figure 4, that number also drops significantly down to 1.65 at the lowest value. From there 1.9 and change. MR. AFRAN: That was on cross section D? THE WITNESS: That was on -- yeah, cross section D, Figure 4.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 19 MR. AFRAN: Thank you. A. So what does that mean. Well, if you recall anything above, if you do your analysis, and I'm just going to be very transparent, when you do an analysis a number of 1.0 on a stability analysis if it's above that, according to the calculation, that means there's more resistance than forces. Resistance to failure than forces pushing it down. Basically a ratio of the forces pushing down to the force of resisting. So if you get a 1.1 or a 1.4 that actually shows that there's more resistance from failure than the force trying too fail the slope. Now, you'd say to yourself, that's a good thing. However, because if it's less then one, technically the slopes in a -- it's in an active mode of failure. However, engineering guidance and geotechnical engineering is not an exact engineering science because if you think about it, the ground conditions, the soil conditions, the rock conditions are very -- they're extremely variable from boring to boring, location to location. So the various authorities on these types of -- these subjects, geotechnical engineering in this case comes up with vertical factors of safety that you should meet. So even though you're at a 1.4 let's say in section D on Figure 4, is that enough. And so in accordance with the United States Army Core of

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 20 Engineers, their manual, November 1994, it's EM, which is the engineering manual, 1110-1-2908, Engineering and Design Rock Foundations. I put a quote out here on Page 5 in the middle. "The calculated factor of safety is primarily dependent upon geometry of a potential failure as selected for analysis and the sheer strength representative of the potential failure surface. Other factors such as groundwater conditions and potential for erosion and seismic -- and highlighted -- I bolded this. The possible blasting use of the rock mass must also be addressed." The other thing they recommend, and it's on the second -- the bottom of the Page 5 is, "For major rock slopes where the consequence of failure is severe the minimum required calculated factor of safety is 2.0." So double what would be considered a just balanced at 1.0 where resisting factors -- resisting loads are equal to failure loads. But they recommend 2.0. "Other slopes that are not so consequential could be at a factor of safety as low as 1.3." However, based on my analysis and our understanding of the site and the proximity, especially the homes that are located literally on the toe of slope of Howell Drive, with those homes I would say that if there's a potential for damage to life of the property,