February 26, 2025, Planning Board Special Meeting Transcript - WEHI

3 of 46 sheets Page 9 to 12 of 115 03/03/2025 06:36:47 AM 9 areas of the site and also tells us what the soils are1 underneath the surface. They're an important aspect of2 the project that will limit how you build your design.3 It eliminates how you design because for example the4 seasonal high water table have, all BMP's have to be at5 least two feet above it. What was interesting, and I6 have soil logs on the board here, they identify the7 seasonal high water through two processes. You dig a8 hole and look for water coming out of the ground and9 then also look for something called mottling. Is anyone10 familiar with the term mottling? It's a coloration that11 occur's within the soil. And that can also be used to12 identify the seasonal high water table. What's13 important about that is that the seasonal high water14 table fluctuates on a daily basis based on how often it15 rains, when was the last time it rained, but the16 mottling doesn't change. The mottling is built on years17 and years of the water always changing. So the mottling18 is what can show you truly the seasonal high water19 table. And what's unusual about these soil logs, and20 it's a lot of soil logs for this site, is that there's21 never any mention of mottling, ever. And in the DEP22 manual it explicitly says you should use mottling23 wherever present to identify where there's a high water24 table because, once again, water levels can change every25 10 day. So the chances that you dig a hole when the water1 is at it's highest level is very low. So that's the2 first thing that I want to call into question with some3 of the data presented here. They only state the4 seasonal high water table is where they find water, but5 the odds are they're underestimating where the seasonal6 high water table is and that is our immediate concern7 because that's one of the initial site restraints on how8 deep you make the basin is. If you can't make them deep9 enough you have to make them wide. So they have a big10 impact on your site.11 All right. And just to hammer the point a little12 bit. For example --13 CHAIRMAN BAGOFF: Mr. Afran, if I can ask,14 there's a Princeton Hydro report dated November 15,15 2024, is that what you're referring to? Looking at the16 table.17 THE WITNESS: No, I'm referring to -- I'm18 referring to -- these are the soil boring logs that were19 presented by the applicant as part of

is that what you're referring to? Looking at the16 table.17 THE WITNESS: No, I'm referring to -- I'm18 referring to -- these are the soil boring logs that were19 presented by the applicant as part of their submission.20 CHAIRMAN BAGOFF: Okay.21 THE WITNESS: That letter was just a review22 of their submission.23 CHAIRMAN BAGOFF: I want to be clear for the24 record.25 11 Let me ask you one question. Is there a date you1 Q. can identify so later looking at record we have a2 reference point? A date of the soil logs.3 There's three dates. There's three different4 A. reports they submitted. One is dated April 19, 2021.5 One is dated February 12, 2024. And then the third one6 is dated April 4, 2024.7 CHAIRMAN BAGOFF: Thank you.8 Some of the designs they presented here are the9 A. bare minimum separation for seasonal high water tables.10 So immediately there's a concern that, you know, if11 they're underestimating the seasonal high water12 elevation. Now, if you went back and looked at the13 mottling you might find that there's not enough space14 since it's already noncompliant with DEP regulations.15 And I would think that the geotechnical engineer who did16 these should provide some testimony as to why mottling17 is absent from any of these reports. It's very unusual.18 I've seen plenty of these, the DEP manual is very19 explicit that it should discuss what mottling is.20 MR. AFRAN: Could I just note for the21 record, a minor point. I think Mr. Walsh is referring22 to mottling as M-O-T-T, not M-O-D, as in David.23 CHAIRMAN BAGOFF: The change in coloration24 based on the soil.25 12 MR. AFRAN: Yes. For the record and the1 reporters benefit, it's M-O-T-T.2 CHAIRMAN BAGOFF: L-I-N-G.3 MR. AFRAN: L-I-N-G.4 MS. MCGOVERN: Okay. Thank you.5 I apologize.6 A. All right. Next I would like to talk about, we7 reviewed all the soil borings to confirm that they did8 have the space necessary for the seasonal high from the9 bottom of the storage basins to the seasonal water high10 table. And unfortunately during our review we found11 they actually missed some of it. In their reports and12 in their plans they do cite some of the borings but they13 don't cite all of them. There are some instances where14 they missed previous reports. I would like to now look15 at Porous Pavement Section 4.16 Could you give me a description as to this17 Q. document?18 So what we're looking at now is

e instances where14 they missed previous reports. I would like to now look15 at Porous Pavement Section 4.16 Could you give me a description as to this17 Q. document?18 So what we're looking at now is the construction19 A. drawings that the applicant had submitted. This is a20 cross section of Porous Pavement 4.21 All right. So you will see they reference22 seasonal high water table at 567 and what they did here23 is they used the report from 2024 to reference the24 seasonal high water table, but if you look back at the25