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tv   Port Commission  SFGTV  November 14, 2021 11:40pm-1:31am PST

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commitment from new leaders to make sure the gains we are fighting for as a city are not lost in the immediate future. thank you. >> next speaker, please. >> good afternoon. i am cathy deluca community living campaign, non-profit work with seniors and add difficulties with disability. we want to restore muni service to pre-pandemic level. thank you to everyone here. the residents fighting, advocates, union, supervisors and s.f.m.t.a. staff. i don't doubt for one minute that s.f.m.t.a. staff cares about residents and wants to deliver excellent transit services. i see a major disconnect between those doing the planning and
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those depending on muni service. you can't plan equitable and just only when you plan for those walking up and down three blocks up and down hills to get to buses running. it should never have been the scenario if all populations were planned for. you can't plan with an outside focus on numbers and data. you can't plan an equitable system when the outreach is digital. you can't plan equitable when it is four weeks long. i have been works in the neighborhood for full year and no way to reach the residents. in four weeks i couldn't do outreach. older adults and people with disabilities feel left behind and tell me they feel stranded in their homes. they don't understand why m.t.a.
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staff might talk to me but not reach out to them. they have to change the way to do outreach. transit will never thrive unless it is planned with the community and not for them. thank you. >> next caller, please. >> i am samuel thomas calling representing the potrero hill. what i have to say is that a lot of people on potrero hill is sick and ill. they can't get no one to come up here. in home support. they help them out and stuff like that. for me i am just getting out of the hospital. i can't get in-home support to
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work for me because there is no bus coming up here to bring them. most people that work for the in home support they don't have cars. they have to use the bus. we need the 10 back and have the 10 go the long distance like it has always been. shortening is not really doing anything. you know what i am saying? that is all i have to say. thank you. >> next caller, please. >> i am senior and disability action. we were part of the coalition to fully restore muni. i would like to use what our speaker before cathy said from
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tlc. build on that. it was basically we really appreciate all of the work s.f.m.t.a. put into it. it was not a team effort. team effort with the community and with the transit workers union. hence, the result is the s.f.m.t.a. spent a lot of time dealing with the push back, dealing with the community buying in, not part of it. not accepting the results or the solutions that m.t.a. come up with. they might be beautiful, perfect onutions. you need the buy in. bring us to the table. you need to treat the community as part of the team. not dealing with that and cathy
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from tlc went in details about it. the plan for 2022 was basically set up a foundation and then study that. determine what the future of muni will be. please take what the community and the twu has said are the flaws of your outreach, flaw of not bringing up to the table and learn from that so that when you start developing a plan for the future you will bring us in as a team. you are going to spend a lot of time with the mess created from not doing that. i know that m.t.a. does not have the energy or the staffing to do that. please work on this. >> your time is concluded. >> next caller, please.
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>> right now there is two options being presented for the j. 10 minute frequency for surface only. 15 minutes for subway option. i would like to propose third option to reduce the number of stops closely spaced which could enable the j to probably run around a 12 minute frequency right in the middle of the plans and that way people don't have to make transfers, they are still at a decent frequency. >> are we still connect. to the caller speaking?
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>> no, the caller hung up. >> next caller, please. >> i have a couple quick comments and then two questions about abandonment. my comments are that there has been a tremendous outflow of concern stated by noey valley residents. i live in the valley. i am part of the restore j work group. the thing that troubles me most there is no technical analysis
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that m.t.a. presented that would support what they call option one. keeping the j out of the tunnel. in fact, the technical analysis supports option two. putting the j in the tunnel at 15 minutes headway. four trains per hour. currently they are running 18 to 20 trains per hour. if we added the j four that would bring it up to 22 maximum of 22 trains per hour. that is well below the 30 that the m.t.a. stated it would be the limit that might create performance problems. supervisor mandelman in a meeting with us suggested put the j into the tunnel right now at the rate of four trains person hour and monitor the situation. if in fact there are negative impacts on the rest of the
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system we can look at that, make decisions about it. right now there is no data or analysis suggesting that this would be a problem. therefore i think we should go ahead in line with the very strong concerns that valley neighbors expressed. two questions about abandonment. i thought the meeting would be focused on that issue. i will throw them out. >> your time is concluded. all speakers have the same two minutes for comments to the committee. i understand we still have a caller on the line. next caller, please. >> david pill plow.
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system does not tell you where you are in the queue. it is very difficult. if you could start my time now. i support full restoration of regular meeting to at least pre-covid weekend service. i know resources exist now and in the future to provide service without pitting people among each other staff suggested. there is too much service in the early morning and later evening and too little service in the day when people need it most. i plan to relate coverage, frequency to capacity and equity at a future meeting, possibly the land use hearing that i believe is up. the 12 could be operated to presidio in california. 21 to downtown and other changes can be added at very little
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incremental cost in trade-off i would not operate both 5 short line and 5 rapid. i would run more service on the 5 long line at this time. the time savings between the 5 local and 5 rapid is not significant. same on the 28 and 28r. coupely cat service. >> 30 seconds. >> i do support operating 14r and 38r not night service on those lines. more local service. i appreciate commitment to continuing service planning and public outreach that needs follow up and monitoring. you discussed cable cars ask city attorney for opinion. untrust and happiness with m.t.a. i made comments on this topic. i can advise further in public or private. thanks for listening. >> thank you. next caller, please.
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>> i am district 5 resident in japan town. i support restoring all lines to pre-pandemic level. every week i see elders at the bus stops for the bus to come. it is heartbreaking. i know 2 is planning to come back. every day that line or any line not running is another day someone can't get where they need to be or walk an extra hilly block to get there. for one of the slides it says 38 is just a couple blocks. for j town and tenderloin that runs on clay. that is three to four blocks. that is not a good talking point as one to two. i don't trust this department to do the right thing without constant public pressure. if there wasn't organizers from
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the public the 31 wouldn't have come back. we have a director who says redevelopment was not bad. i don't trust this department. we do need more revenue. where is m.t.a. to push? charge for parking on sunday. the m.t.a. says a lot of things and does not back up with action. i believe it when i see it attitude. please restore lines to pre-yuzuru hanyu level. >> next caller, please -- to prepandemic level. >> this is the director with san francisco transit riders. thankful for the proposal to give the service we have been missing. it is a difficult situation, but we want to acknowledge the supervisors and riders who felt
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they are no other choice than to get loud and demand change to get vital lines restored. we are glad to see the plans. we know this isn't the end of the line. we need significant investment in muni operations to fund and expand services. as the callers mentioned we have to learn from this process if we succeed for a more equitable transit system and process. that is the only way to get political will and power to restore service from muni. we need in creased accountable from community and labor for the stakeholders and secure funding for transit system that has faced decades of disinvestment. we can't emerge more divided. it is critical the board of supervisors and mayor and public
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are aligned and supportive of the accountability mechanisms. impact to communities and identifying the funding for progressive resources to restore lines. anything short leaves our riders in economic recovery. as we move i hope we can find the political will and center the community and riders and labor most impacted by the service changes. thank you. >> any further callers in the queue to comment on agenda item 3? >> there are no more callers in the queue. >> thank you. with no more callers in queue, public comment is now closed. a quick question.
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we have had a lot of time last hearing discussing the consultant walker. i want to clarify with director tumlin whether the contract and services for which mr. walker was retained to conduct this survey and this was his recommendations regarding service restoration is that concluded and the service concluded or ongoing? >> just one word of correction. chair walker's company had no role in the survey. that was done entirely in house by the staff. walkers term did analytics to shape options. i believe there may be some ongoing scope but for the most part the work that mr. walker's firm has done is complete.
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m.t.a. staff will carry it out. >> thank you, director tumlin. i want to thank all of the folks who called in. it was very important comments. i want to make one final comment. something i was thinking about. in light of the discussion about shortened lines. in particular i appreciate ms. petty from senior disability action talking about she framed it transit first looking at transfer most which is interesting. i do think that it does highlight a real issue. i think that looking on the map of coverage it is easy to see a case for investment in core lines and requiring transfers and look like you are covering
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the city. i want to make sure especially as we look at the most significant issue. winter 2022 changes are adopted, proposed and adopted and we are talking about if next step. i want to elevated i would like to see as clear as possible commitment to restoring the full length of these lines. remain a little concerned with the lack of clarity around the long-term plans. i appreciate further engagement before the shortening of the line would occur. i hope we can restore those lines. i think that the impact of forcing additional transfers is particularly harsh on senior and disabled riders, folks with mobility impairments.
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it i lengthens the trip for everyone. for all of us and any of us who use muni regularly know that if you are planning a trip that involves one or two changes it completely changes amount of time you have to allocate. more can go wrong. it is a longer trip. the final piece. we can talk about this further offline. i think it is important to recognize forcing more and more transfers does not necessarily save us very much. there is this assumption that somehow it is 21 terminates at civic center and continues down market and there is a massive cost savings. at the level to come back right now i think it would be like one or two additional buses an hour
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required if you were to cover the entire lot. one or two additional buses to run that line. which you can achieve by the 5 a few blocks away. you could run more buses. i pick up some of the extra folks there and a couple buses to serve the whole line. obviously, we have talked about trade-offs and moving parts here. when i looked into it i am surprised how low the savings seem to be by shortening these lines. it doesn't make sense short term when we have this usage and downtown traffic. there is a case for that. i appreciate that line coming back to understand the thinking
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of waiting. extension further downtown. i would like to see more clear commitment that lines like this will run all the wayne downtown to original route as themuter track and workers getting down town. i hope we can get more clarity on that. those are my -- really my final thought beyond thanking everyone foreign gaugement. it is a long hearing. appreciate the m.t.a.'s responses to the question. the work that has gone into the recommendations and i want to thank everyone for their work and thank our operators and stafffor being here today.
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i don't see anyone else on the roster. if there are no further comments or questions, we can wrap this up with those thanks. i would like to continue this item to the call of the chair again, especially since we have a series of recommendations that may go into effect in february. there may be a desire to bring this back one more time depending on the next rollout. mr. clerk call the roll on the motion to continue. >> motion offered by chair preston the hearing be continued to the call of the chair. vice chair chan. >> aye. >> mandelman. >> aye. >> chair preston. >> aye. >> mr. chair, three ayes. >> thank you. motion passes. thank you all again. please call the next item. 4. hearing to receive progress updates on the seismic retrofit
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options for 301 mission. based on public documents in our file that being 160975. members of the public to comment on this call in the call-in number 415-655-0001. today's id24922118986. after you entered the id press pound twice and then star followed by number three if you wish to enter the queue to speak. >> thank you, mr. clerk. i am going to in a minute here hand it off to the sponsor of this item. before i do let me thank mr. peskin and the callers for their patience. it is a long hearing already. let me assure you that these
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items are not agendized in importance of order or order of importance. we are looking forward to this hearing on this extremely important matter. thank you for your patience. i will turn the floor over to supervisor peskin. >> thank you, chair preston and supervisor chan and mandelman for the opportunity to bring this item before you. i wish that the 301 mission street mel enemy yum tower -- tower behind us but that is not the case. as you know, going back to 2009 when the first unit in that building were sold the tower had already begun to sink
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differentially, to tilt far beyond what the projections in the environmental analysis yielded which is tropical. so far as this board of supervisors actually recently held a hearing on a different building and were concerned about the lack of seismic and geotechnical information in that report. in this instance over the life of the structure, there was projected to be four to six inches of uniform. the building not differential settlement, no tilt. this building like the one we considered the other day is in an area of town that was not originally tera fir mabut filled reclaimed lands. when i started the hearings in
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2016 on the sinking and tilting, the building had already tilted almost a foot and a half to the northwest and sunk approximately a foot. there was a lot of litigation which we are all aware of. that litigation has been settled. we don't know the terms of that. i am led to believe the homeowners association receive the range of individual homeowners received benefits. we do know that the city and county of san francisco did not participate monetarily but did make available at no charge the portions of the public right-of-way along mission and fremont streetses where a voluntary fix casing and tiling
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system that was supposed to stem the continued sinking and tilting of the building and maybe even restore some of it and sadly, unfortunately, it would appear that the fix has exacerbated the sinking and tilting that is now approaching two feet of tilt at the top. i realize this has gotten a lot of media attention and is the issue. it is not what we are here for today. we are here, one, to hear why experts, structural and geotechnical experts think the fix caused the accelerated differential settlement. two, to hear from the department
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of building inspection who is the permit issuing authority and their plans now and in the future as well as from the edrt, the design review team that has been a second be set of eyes for dpi, what their role has been, what their assessment of what went wrong in the fix and what their role is going forward. there is good news. the good news is and we will hear about this shortly. of 52-inch 36-inch casings on fremont and mission streets when work was halted in august 23rd there has been one test casing and it's would appear the
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techniques used for sinking that casing did not lead to any additional settlement. we will hear about that. then colleagues we hope to have lessons learned. i have a series of questions you should feel free to jump in. obviously, this building is unique in san francisco because it is built out of concrete and not steel. 57% heavier. load is heavier. we know that the foundation system does not go to bedrock. it has 10-foot matt slabs supported by friction piles. you will hear about the column of sands and the substrate beneath the tower. with that the project that the
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fix is a product of the millennium homeowners association. we will start with the hoa as to what the outcomes of the fix have been, what is going on with the building and what their plans are going forward. we will hear from the structural engineer of record who works for the hoa who participated in our 2015 hearings as well as matt who was the project manager for the hoa overseeing the construction doing the actual on the groundwork.
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>> from this process it was unanimously endorsed by an independent third-party panel of experts after a peer review led
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by the university of washington. member of the berkeley academy of alumni. once consensus was reached. the best approach in the foundation and long-term performance of the tower it was presented to the city's engineering design review team. after the review they also improved the design. in addition to seeking out the best available experts for the design the tower sought out most qualified team for construction. the lead design team of engineers from the mediation process were chairing over to the construction project itself. for construction only one obvious choice to select a contractor shimek construction.
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they have delivered on local projects such as bart, caltrains and performed for the san francisco transit agencies. they sought out and relied on best experts and professionals to address the settlement of the tower. lastly, the tower has remained safe to engineering certainty. on this point there continues to be consensus. in the final declaration it was evaluated and determined to be structurally sound. that is why this is an upgrade not repair. after much consideration the millennium tower determined it was best to proceed with construction to improve long-term performance of the building. this including tilt construction, further projections over the long-term.
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on behalf of the tower community we are grateful for the engineers and construction professionals working with our team to complete the upgrade. now with that backdrop i will turn it over to our lead engineer to update the board on the progress. >> good morning, mr. hamburger. >> good morning. i did attend to transmit a powerpoint this morning. i wonder if the clerk has that available. >> i did not get such a thing. i don't know if the clerk got it. >> through the chair to mr. hamburger, no, sir, i did not receive the powerpoint from you. i have a presentation from the department of building and inspection on this topic. >> i am sorry about that. if i can share my screen, i will share it. if not i will talk. >> we can help you share your
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screen. if you can start with your bona fide des in this field. >> the screen is shareable now. i am ron hamburger. senior principal with simpson. i have approximately 47 years of experience in structural engineering. education, construction and failure investigation. i am a member of the national academy of engineering. past president of the structural engineers association of northern california. california and the national council of structural engineering associations. since 2011 i have chaired the follow veer committee of the american society of civil
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engineers that developed the structural engineering requirements of the engineering code. if i may, i would like to talk briefly. supervisor peskin has about the problem and solution. millennium tire is constructed at the corner of mission and fremont street. like most of the financial district south of the market area of san francisco, underlying the city consists of artificial fill since the gold rush. young bay muddy possit is from the deposits when the san francisco bay covered that area. deep layer now 70 food down 70-f beach sand did not cover. [indiscernable] a very deep layer 150 feet of
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material called old lay clay. eventually about 230 feet down formation bedrock. the tower like every building constructed in that part of san francisco prior to 2010 is a series of piles that extend down into the dens sand layer for the foundation support. the reason the building is settling is that under the effect of the building weight as supervisor peskin said is significantly larger than buildings constructed prior to that is causing a process called consolidation of the old bay clays beneath the building pile. consolidation is the pressure created by the building and by the watering of the surrounding site to allow construction of the adjacent buildings. basically squeezing water out of the old bay clay.
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that squeezes the water out it is like squeezing water out of a sponge causing volume change that is allowing the site to settle. tilting beneath the building as shown in the slide is not uniform. the layers have different thicknesses on different sides of the site. construction add jay sent to the building including the transit center immediately to the southed removed the soils present to the construction and constructionrelieved pressure o. the building is tilting to the west. the goal of the voluntary upgrade is to arrest that perfected settlement of the building and to allow recovery over a period of years.
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we accomplished this by new piles underneath the sidewalk on fremont and mission street at the side of the building. jack load off the existing foundation to new piles of rock and transfer that load down to the bedrock to stop the consolidation of the old clays. >> if we can go back a little bit. i know this is going back i recall it started on the mission site before the excavation and installation of the wall on the transbay terminal, and that was
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initially ascribed to more de-watering of 301 mission street site than originally predicted in the earlier calculations and in further allegedly exacerbated by the de-watering of the transbay site. does that sound right to you? >> that is correct. it is settling since construction initiated on it. effect of de-waters is reducing the -- when you de-water it decreases the effect of waste of soils above or below the water table to create more pressure and consolidation. the building did not tilt until 2009 when it started on the add jays sent project it settled
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straight down. >> my recollection is the same. >> as the structural engineer of record does that mean that you designed the foundation system or somebody else designed the foundation system? >> i was not the structural engineer of record for the original construction of the building. the original structural engineer of record designed the foundation system, they selected the number of piles to be used,
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how deep they would go, designed the foundation map on those tiles, it was done on the basis of recommendation made by the geotechnical engineer of record for the original construction. >> remind he who is the structural engineer of record originally in the foundation system? >> original structural engineer of record was. [indiscernable] >> right, yes. >> tread will was the geotech? >> that's correct. >> going back again to the original if you will. >> was this a process in implementation failure? what do you think the original failure was in.
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>> i am not comfortable on this. i have not studied that in any detail. my understanding is that the original geotechnical engineer for the project did under estimate the weight of one of the layers of soil. it was assumed when the project was originally discussed that the de-watering for this project was going to be only during the period of excavation and construction. . [please stand by]
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>> digging piles 270' deep in the rock. with 36" diameter. once that's done, a 24" diameter steel pipe approximately 240' down through
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the center of those 36" diameter casings to the top of the rock and then they drill down into the rock and that's another 30' and that's. once the pile is installed, they would totally be which is about 15' below grade in a 10' set. we have attached onto the existing and existing foundation will be basically extend that foundation out to
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encompass new the contractor's technique and installing the 36" casings and the 24" casings. inadvertently removes soil from beneath the structure. and just squeezing the pile and resulting in volume changes. and piles have been installed
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and resulted in volume change and settlement. a secondary cause into the sand and support the existing piles that have dense fied them and we think that has some expense as well. >> supervisor peskin: and just relative to the behavior of the structure during the insulation of the casings and the piles, maybe we can just take it from the top. the design that you propose that the edrt reviewed and were otherwise peer reviewed as
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mr. lip said consisted of 52 casings, correct? and 52 piles that you would in essence tie back to i assume you started with the casings. when did you start and how -- when did you start detecting the accelerated differential settlement? >> it started in may of this year. we began to detect small amounts of increased settlement almost immediately. and as additional casings and piles were installed, the increase in settlement became more severe.
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by the end of july, the contractor had installed a total of 33 of the 52 casings consisting of call the casings along fremont street and about two thirds of the casings on mission street. they had also installed at that time, six of the 24 -- i'm sorry. three of the 24" piles. at that point in time, i became concerned and i asked the contractor some following 36" casings continuing with the 24s so they can understand which of those two operations and.
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>> supervisor peskin: as of right now, 6, 24" piles. >> those are located at the south end of fremont street. from the driveway north. >> supervisor peskin: and then you see 36" casings after the 33 up until you did the quote unquote test recently? >> is that correct. >> and they permit us to install some additional 36" cases. as of today, there are a total of 36 installed. >> supervisor peskin: and, are you still going for 52 or are you revising the plans to have less casings and piles?
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>> we did submit a proposal to the city. we have not yet seen impact. >> supervisor peskin: and the quote unquote successful installation of the test casing and subsequent casings, what did you -- what was done differently relative to method? >> on the 36" casing, we did much more careful control of where the ends of the casings would be stopped -- it's possible that we do 100' length. the contractor has to make splices in the casings and so we controlleded where those splices would be made so that the tip of the casing would not
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be that could be pushed up into the casing while -- we also acquired much more careful control on the depth of plug and the end of the casing and the amount of water fill in the casing while they're installing it to provide waste at the end of the casing to prevent material from piping up into the casing. >> supervisor peskin: so less ground. >> we also put measures to isolate the installation equipment -- to isolate the vibration from the installation equipment from the piles that had already been installed. when we installed the pilot casing a few weeks ago, we have extensive measurement of operations both at street level and the casings and at depth within the same layer and we
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have determined that we have successfully mitigated the vibration. and ground loss measures on the 36s also appear to be successful. >> supervisor peskin: and, the techniques that are being utilized in this are techniques that have otherwise been utilized in other situations, is that correct? >> the installation techniques that are being used here have not been used in the san francisco bay area previously, but the contractor who is doing this work has used these techniques and other sites around the city. >> supervisor peskin: so is this good to new any explanation as to why these techniques that have been used in other places in the united states were not implemented earlier in this between may and
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when you ceased in late august and commence the test recently? >> i have no way looking at that. i can tell you the soil at every site even at different sites within the city vary quite a bit and the techniques that are used in one place technically may not be as effective in other locations. >> supervisor peskin: and just in the placement of the first 30+ casings, what kind of monitoring regimen was employed then versus what has been since implemented in the pilot? >> there are a series of 38 settlement markers that are surveyed upon. in the basement of the building
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that have been surveyed every week since the construction started. in addition, there are a series of prisms mounted on the side of the building and also at the top that give digital read-outs not only of settlements, but also horizontal movements of the buildings at different levels. those also were being monitored at a weekly basis. we are now monitoring a prism on the side of the building.
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>> supervisor peskin: so the difference is not that you installed more prisms or more monitors, but was that you monitored them more frequently, is that correct? >> that's correct. >> supervisor peskin: but it's not the monitoring that decreased the differential settlement during the test pilot, it is the change, means and methods? >> that is also correct. >> supervisor peskin: okay. thank you for all that. please proceed. >> okay: in late august, when
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i put the moratorium on the compilation. the tilt on the plot at the top is tilted to the north. the plot on the bottom is tilt of the building to the west towards fremont street. in 2009 with construction completed, the building was holding about 4" to the north.
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>> in november of 2020, when construction started, the building was helping about 7" to the north and 17" to the west. in august of this year, when i instituted the moratorium and 23" to the west and as of today, it's about can. >> supervisor peskin: mr. hamburger, i've heard in the past where we have a duty as the department of building inspection and the board of supervisors to inquire.
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at what point, should we particularly in a seismically proned region. at what point do we worry about structural failure. ? >> it's an excellent question. i've been asked this a number of times. i started back in 2018 and what we've done -- what we've done is we created an analytical model of the building. this is the same type of model used the design what the building code called the maximum considered.
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1500 years or so. it has the magnitude of the 1906 san francisco earthquake, but has an indentation of a location that reduces more severe compared to as i said, the building is holding 12" to the north and 28" to the west. we had evaluated it previously and the ezrt reviewed and concurred that the building was safe at that level of deflection we lacked at the building as much as almost 3' to the north and almost 80" to the west. and we've concluded that the building is still able to safely resist its maximum considered earthquake shaking not that we expect the building
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will ever be permitted to go that far. i will mention that the edrt has seen those results but has not had the opportunity to review that. [please stand by]
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>> we have successfully tested the 36-inch casing. our next step is testing 24-inch casing in two weeks. based on the results of the testing of the 36 and 24, we will be able to project how much settlement will occur to the building and how much sloping.
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we will have a conversation with the homeowners and with the building department as to how much additional sloping they will accept. we will trim the project to allow the piles not acceding that limit. i will note the upgrade is voluntary. the piles that we install and attach to the building will improve performance and will reduce amount of settlement that occurs over the years. at this point we are looking to see how many piles we, the city, homeowners can afford without causing excessive tilt in the building so the behavior in the future will be improved. >> mr. hamburger, i thought there was a chance to find out
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if it was on a specific slide or wait until the presentation is done before asking your question? >> i think it is just a quick question between this slide and the last slide. maybe i missed the point here that was already made. you mentioned from a technical perspective you consider a tilt up to 40 inches is acceptable limit. knowing that right now from what you indicated the tilt is 9.5 inches north and 23.5 inches west. in the event from your estimate or i don't know if this is the right question to ask you. in the event that -- because the work has begun and it tilts more
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and settles more unexpectedly. in the event what you are about to do now with the new solution that you are moving forward in the event it doesn't work again, how fast do you think -- how much time do we have until it is no longer acceptable? >> before the initiative the building was settling about one eight inch per year and tilting at one-half inch per year. when we stopped construction of the piles in august the building returned to those rates of settlement. we are currently at almost 30 inches of tilt. we have another 10 inches of tilt which could occur at the rate of a half inch per year. that could be 20 years if we did nothing. >> thank you.
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>> thank you, supervisor chan. i apologize for cutting you off, supervisor peskin. >> none of us are geotechnical or structural experts so this may sound like a simplistic question. mr. hamburger, do you think this building would have been better off without the fix or is it too early to tell? what is your take on that? >> if we had not done the fix, the building would have settled and tilted as it currently has today in about four years. the building would have been better off today but not better off four years from now. >> four or 40? >> four. >> even with the limited number of piles that we have installed at the moment, if we put these piles into the building and off
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the building to the piles that will improve the building's future performance beyond what it would otherwise have been to the extent we can successfully install additional piles that will improve the building future performance. i would not say the building would have been better off if we had not done what we have done. >> all things being equal, the fix was not necessary? >> in our opinion the fix has never been necessary from a structural perspective, from a safety perspective. >> got it. you are saying if this thing does not reach equalibrium and sees tilting eventually it is going to get to 40 inches or 28 inches? is that fair to say?
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did you say that? >> 28 inches now. >> i thought you said 23.5. then you said 28 inches. i am confused. >> you are correct. the reason is summing the tilt to get the tilt quantity in the north west direction which is more of the tilt to the north arwest. >> got it. consolidation causing the tilt we are not installing piles is self-limiting behavior. if you think about the sponge someone squeezing water. if you grab a wet sponge and apply pressure with your hand and you squeeze water out, water will come out for a while then stop. consolidation is a self-limiting
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behavior. we expect to happen over time as the consolidation continues and more and more water is squeeze the out of the soil, it will self-limit and stop. i think it will self-limit in about 40 inches. >> 40 inches. you are saying you think it will get to 40 earlier that 40 is the acceptable limit? >> yes. >> then if it goes to 41 or 48, which the edrt and other peer reviewers haven't looked at that is the point of no return, in your estimation? >> i wouldn't call it point of no return. i would call it a point at which the building's ability to resist
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maximum earthquake. [indiscernable] >> maybe this is not a question for you but mr. eaga in who joined the call. with all of this and sorry for the technical termmucking around in the dirt and the existing load measured in kips, do you or does the goio tech think there is any defamation of the substrate? are different layers sheering within the subsurface? >> no, i don't think there is
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sheering. i think that what the installation of piles has done has -- obviously if you get settlement, you are causing additional consolidation settlement or second dairy compression settlement during this process. i don't think it has caused sheering of concern within the sub soil strata. >> relative to the condition of the matt, the 10-foot slab matt. i will ask this question. i never did get answers or good enough answers to this question a half step years ago when we were holding the hearings. was that done in one pour or multiple pours? do you know?
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>> i do know that was done in one continuous pour that lasted more than a day. hundreds of trucks would come and depossit is the concrete. >> it gets hot. did you cool it. >> i was not the structural engineer. it is typical in large foundation pours of big buildings like this to ice the concrete. i assume that was done here. >> this is a separate question. i will start trying to turn it over to the next speakers, but i mean again, none of us here are remotely experts in this field. i did start out as an earth sign
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measure in the math kicked my behind. i have not spoken to most of these folks, but i have the same access to the internet and the television that everybody else does. i see this parade of credentialed experts and i can look them up on the internet. they are structural or geotechnical engineers in good standing, licensed in the state of california. we all know their names. some of them have taken upon themselves to e-mail me and robert pike is in the record and date williams we saw on tv and somebody from uc berkeley and larry carp and the list goes on. one was concerned about dishing
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of the matt. any thoughts for mr. eagan or mr. hamburger if there is defamation of the mat. >> it has dished. when detailed measurements of the elevation started to be taken in 2009 with the survey markers, it cuts off the addition of the matt. we are continuing to monitor those with the survey. the mat has not improved at all since 2009. the building has been settling and tilting at the rigid bottom as you see on the slide here with no additional dishing of the mat. i would like to note my analysis of the building included a detailed model of the building
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map. before we apply an earthquake load to the structure we apply that dishing to the model to stimulate the effect of what has occurred. the analysis indicate we have reviewed it and that dishing has not compromised the mat. >> i have been in the basement of the building and seen the cracks. there is obviously water in intrusion.does the modeling tako account any of the corrosive activities occurring in the basement? >> the water leakage that you are referring to as well as the cracking of the basement walls which are not in this building. it was constructed together with adjacent mid-rise building.
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the garage for both buildings is in the five level of basement of the mid-rise knowledge. all -- mid-rise building. all of that damage is in the mid-rise building. i have not evaluated the safety of the mid-rise. it has not compromised the tower ability. >> okay. mr. eagan, do you agree with that? >> yes. >> thank you. i i assume all of you in this relatively small tight admitted expert community know one another. do you talk to each other? are these people looking to be on tv or what is your take about the skepticism we are seeing from other industry experts on television set? >> i don't really care to speculate as to the motive of
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these individuals. i will say in the san francisco bay area there are at least 2000 structural engineers. i assume several hundred geotechnical engineers all members of the structural engineers association of northern california. i was once part of that. the fact that a half dozen engineers think there is a big problem. i wouldn't suggest that is representative of the engineering communititive in the bay area. i will also say the engineers who have been vocal and in the press could not possibly have done the level of analysis i have done over the seven years i have been involved with this building. >> thank you, mr. hamburger. you are not speculating that is a good thing.
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i have not spoken to most of them. i do always read their submissions with interest. would you like to wrap up? we can go to briefly in charge of overseeing construction for the homeowner's association. any last slides, mr. hamburger. >> one last slide on the project schedule. there is a detailed schedule developed by the contractor 22 month construction period. at the time construction halted in august at my direction about 10 of those 22 months had elapsed. the project was on schedule at that time. assuming we get permission to restart construction, i am saying in december of this year,
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it will take about another year to complete the project. that would be december of next year. steps will be permitted and will have arrested and stopped further settlement of the building upon submission and allow gradual settling on the south and east side with the effect of recovering the tilt that has occurred over time. thank you for your attention. >> thank you very much, mr. hamburger. congratulations on the new means and methods that have proved at least initially successful. i wish they had been implemented earlier in this fix. we are where we are. mr. dutro, good afternoon. >> good afternoon, supervisor
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peskin. thank you for giving us time for discuss this project. i will be very brief. my role is to oversee the project for the homeowners, taking into account the budget and the schedule. we have at the same time engaged a mechanical engineer to review the interior of the building to ensure that the interior of the building remains functional for the homeowners. then in regard to the intrusion that you mentioned, supervisor peskin as mr. hamburger indicated in the parking garage underneath the mid-rise building. we have a design team designing a fix to water proof that section of the building to keep
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the residents safe. there is no currently no life safety issues associated with the interior functions. we will continue to monitor those for the homeowners. >> thank you. one quick question. relative to the integrity of the mat slab. do you know whether or not that thing was iced when they did it in one pour? >> no, i was notes involved in the original construction. >> have you undertaken any ground penetrating radar investigation of the mat? >> no, we haven't done anything to that extent. we relied on professional engineers, hamburger, eagan to guide us to the activities and further investigation would be
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needed to ensure the safety of the building. >> they have not recommendedded using ground penetrating radar technology? >> no. >> if i may. as part of the original investigation performed back in 2014-2015-2016. gpr would not be use full because of the depth of the matter it could not penetrate. [indiscernable] through the depth of the mat and removed from the mat and examined. there was no significant be cracking in the cores. we are confident that concrete is in good shape. >> thank you, mr. hamburger. if there are no questions, mr. chairman, i want to thank the hoa and their three
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representatives, four representatives for their presentation and answering of questions. i will move to our department of building inspection. i don't know if all of you are familiar before patrick is with us to ask questions. mr. ferrara has a powerpoint and is an engineer so with that. if you can walk us through the role of d.b.i. in the permitting process that would be greatly appreciated. >> good afternoon, supervisor peskin and the rest of the committee. as mr. peskin has said i am new to the department. i am the deputy director for permit services. i have studied in late september
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working for 40 years in the industry in design construction and previously served in building departments throughout the state and in private sector. in the past few weeks i acquainted with the project and the department has control oversight and is actively participating for the review of the proceedings during construction. you have heard quite a bit of technical information about the project from mr. hamburger. my focus here is to underscore the d.b.i. role regarding this project. current and future oversight as you said at the beginning of the presentation and the current status of the project. i will then hand be it over to
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professor dear line of the engineering design review team and dr. ben turner who we have since retained from dan brown and associates a national drilling expert in the field. >> the role of d.b.i. as most building as any building department is that to ensure that the building code is being enforced to the maximum extent possible. the building codes offer clear and state guidelines. they are acceptable and what we are here to ensure that construction appears to those boundaries.
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i think, john, you need to mute your microphone. essentially we are driven by design proposals and constraints. we don't tell the design professional, project sponsors what to do. we ensure the proposal is code compliant. that gives us a stronger position to guide and enforce the code without directing the design or construction. this is how all building departments work up and down the state and across the nation as well. if the project varies from code compliant we ask them to correct it. if necessary to shut down operations. public safety is always our first intent. department uses construction proposals, complaints and
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observations as a prime resource of input to ensure the building codes is commyatt. we -- compliant. this allows us to review the scope of work. we have a highly educated team in my career. san francisco plan check engineers are probably the most qualified that i have seen in the building departments that i have administered. we have several advance dee dee's and structural technical engineering here. they are involved in the retrofit. we once the building permit is issued. it will be to inspect the project to make sure it com ports to the plan we were approved. we oversee special inspections
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and materials, tickets delivered to the site. last we respond to complaints of unsafe conditions. that is what we are doing at the millennium tower. in this case we have gone beyond our original scope in several areas. one of which is that we have scheduled biannual inspections to go through and ensure safety of the structure. any minor code violations that come along with those inspections are rectified along the way. the homeowners association have contracted with several other inspectors or teams to go through and do an analysis of the building. we review those and comment on those as necessary. of course,
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we have been instrumental in compiling the engineering design review team and this additional layer of expert oversight helps supplement the internal expertise we have. this continuous monitoring off the project and the construction that actually led to the discovery of the accelerated tilt that we experienced this last summer. >> mr. hamburger made a point saying that he on behalf of the project sponsor of the homeowners association halted the work in late august. what role did d.b.i. play? can you give us background on
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that. clearly d.b.i. even though you knew there was accelerated settlement did not invoke powers to halt installation of the 36-inch much casings and 26-inch piles. tell us behind-the-scenes considerations? >> from what i understand the monitoring of the settlement was essentially started around the same time as the 36-inch casings were beginning. it wasn't until june 23rd that we receive the data from the design team and the field. at the same time we were involved in the changing of the scope from the 52 piles to 42 piles mr. hamburger talked about. essentially we began reviewing
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settlement data as soon as we got it, and you heard mr. hamburger talk about halting the 36-inch casings and continuing on the 24. this was kind of methodology to make sure that it was, you know, what was responsible for the settlement. the 36 or 24. halt one to continue on the other one. this process of deduction and communication back and forth between the engineering design review team and the design engineer took some time. eventually we requested that they halt the continuation. mr. hamburger was the ultimate decision-maker to do that. >> aren't you guys the ultimate decision-maker? you can issue stop work on
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construction of any kind anywhere in the square files of the town, can't you? >> we can do that. this is a consensus of review. the conversation that happens between the design engineer, edrt and d.b.i. is one of general agreement. it takes all three of us to make that decision. yes, you are right. we do have that ability to do that. in this case it was just suggested that they stop. >> so they stopped at your suggestion. please proceed. i know that my three colleagues are about to mute me. let's go on. >> i can go through this slide
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quickly. i did say earlier we oversee and don't determine the means and methods for the contract. that is up to design professional and contractor to come up with that. we will talk about the timeline quickly. i touched on this a moment ago. this is just a rough visual for the ongoing proceedings starting in may when the 36-inch much casings began. then we went into the 24-inch casings. it was discovered the accelerated settlement was going on. there was a period of discussion before the proceedings were actually halted.
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then a discussion again to restart with the pilot you talked about in early october. during that process also it was decided to get in additional oversight. because it is means and methods we found dan brown and associates a nationally recognized drilling expert to join the team to evaluate the means and methods for the installlation. i wanted to start this by saying that conditions at 301 mission are stable. the building is structurally sound by all of the information that i have reviewed and the eert has had. we know the building is habitable and serviceable
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through various inspections and we monitor with the help of the homeowners association and their team of experts that come in and address matters as are needed. the current tilt is at 22.5 northwest of the building. that is holding steady. we had successful installations of the pilot piles. we proved it's on pile number 34 as well. the elevator. >> 34 of 42? >> that the 34 of 42, that's correct. >> the 42 as opposed to 52 permanent casings and piles? d.b.i. signed off on the revised lester number of casings and piles? >> i have to defer to my team on that. i believe that.
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patrick. >> thank you, supervisor peskin and chair preston for holding this hearing. we have not signed off on the reduction from 52 to 42. it is currently being reviewed. >> mr. reardon, while i you on here. it is not fair to ask mr. ferrara. can you tell us how the members of the engineering design review team were selected? and who they work for? >> yes, supervisor. i wasn't in that department at the time either. i believe it included the city administrator at the time and decision was made in consensus with d.b.i. along with the city
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administrator to select this team of professionals. >> do you know how it worked? >> i am not aware exactly how that happened at the time, supervisor. i can get back to you with that information. >> so they were originally hired and paid for and worked under then city administrator naomi kelly and that function was transferred to d.b.i. they are now consultants to the department of building inspection, is that correct? >> that is my understanding, yes. >> supervisor peskin, i want to go to supervisor chan with a comment. >> thank you. my question is earlier mr. hamburger said the limit for this tilt is about 40 inches
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from acceptable design standpoint. do you agree to that? >> supervisor chan, we actually just started those discussions this morning in a meeting. the information is relatively young. in front of the edrt. there was about two hours of very technical discussion this morning. we are in the process of reviewing that. >> what will happen? i am curious in the case that you have a difference of opinion about what is an acceptable limit? what is the process to resolve that difference of opinion? meaning, you know, whether you find it too much or how would you do that? how would you resolve that if you don't agree that 40 inches
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is acceptable limit? >> that is a great discussion. it is very -- it is a series of. it is a discussion among all design professionals. as well as the members of the edrt. we go back and forth. i have seen greg dear line and marco on the team request additional information from the design professional and they are to prove that theory for the engineering design review team and come back and prove it or refute it. it is that process of back and forth. eventual consensus of everyone that we can move forward that results in the decision or the way to go. >> in my line of questioning was
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to mr. hamburger. the attitude of supervisor peskin asked. without the face, you know, we are seeing, you know, the challenges of that the tower would face in terms of tilting would have significantly impacted without the fix within four years. with the fix maybe we have like 20 years. would you agree to that or do you agree with his assessment? >> my experience with this type of building and -- i'm sorry. my experience in fact i was asked by internal executive team about that same thing.
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>> their visual cues to what is going on at the building. if we come out of an earthquake and the building has suffered trauma of some sort. it is not necessarily catastrophic effect. it is not brittle. you will see beams and that sort of thing. these official cues are fuses that are designed to alert us ahead of time as to remediate building or evacuate the building and demollish it if needed.
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>> okay. thank you for that. i personally have not been into the building. sounds to me there seems to be some visual cues from what supervisor peskin had talked about earlier in terms of the cracks that he was seeing. thank you so much. i am done with my questions for now. i may have more later. thank you. >> thank you. supervisor peskin. >> let's keep going. >> next slide please. what d.b.i. is doing. during actual installation is that we have set a threshold. design team and engineering design review team has agreed a quarter inch maximum settlement
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is what is acceptable. if it were to pass this we would pause construction evaluate and react accordingly. during the installation, dan brown and associates monitored the last two casings to make sure that the program for installation is being followed and that it is proving out and the results have proved that minimal settlement occurred using these procedures. the department sends out a senior building inspector every single day to make sure that the monitoring is going on and that we are recording thepertty net data to submit to the edrt for review after reinstallation. the daily measurements are taken. mr. hamburger told you during installation these are hourly
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measurements and the measurements continue to happen daily basis. >> two quick questions. i assume that the stepped up monitoring would be applied to all future installations not just the test casing and the test pilot? >> that's correct, yes. we have seen that we get better or more telling results from the exterior prisms the reflectors on the surface of the building as it reacts to the work going on. the higher the prism the more movement to be reflected on what is going on at the foundation.
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>> it is not a show stopper. is the project sponsor paying for d.b.i. staff time on all of this? >> mr. reardon, i will ask you. >> not as of right now, supervisor peskin. we are looking at the resources we are pouring into this project and continue to and we are evaluating that right now. >> you do have the legal ability to charge for your time, i assume? >> i will have to check with our city attorney on that in relation to what we can and cannot charge for. we have charged a fairly sizable amount of money at the issuance of the permit. i can check on that to see what it is we can do. >> mr. ferrara or other reardon, it sounds like the hourly prism
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measurements and ground vibration monitoring for the test casings and new means and methods are being provided to d.b.i. in realtime or close to realtime, but it sounds like that did not happen between may when this project started and june the 23rd. why not? >> so the plans issued required monitoring. it stated that if the monitoring exceeded specific numbers that the design professional responsible for the project was to stop the work. that is what is drawings indicated.
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prior to june 23rd we requested those numbers to review. [please stand by]
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and then we review it and once a week we get together as a team. the design professional and d.b.i. and d.r.t. members and we review that and discuss it and see what we learned, if anything. decide to act on it, slow things down or analyze it a little bit more or move forward. next slide, please. i've covered this already, daily inspections by the building inspector to go out there, weekly coordination occurs.
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as well as we've asked mr. hamburger to come up with that threshold, right? what we consider a structural safety issue with the building and that's currently being reviewed. every complaint that is -- that arises out of the building we actively engage in to review it and to get compliance. and ultimately, we're making sure that the building continues to be habitable for the occupants and serviceable for the building maintenance. you know, make sure the sewage is running the right direction and the elevators and so on and so forth are working correctly. if the soil settlement reaches more than a quarter inch, we ask that the retrofit stop and we caucus how to move forward.
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>> when you say for casing, installation, does that mean casings and piles? >> correct. so there is a casing that is run down for the 24 as well, but, yeah, people tend to use piles for the 24-inch as well, but there is casing that is run down for the 24 inches as well. >> i'm saying is the tolerance for shutdown a quarter inch per casing and per pile? >> no, it's per installation, so it's -- well, actually, i'd have to ask mr. hamburger about that. >> supervisor peskin: okay. remember that through the process of elimination, what we realized was that the casings are causing differential settlement and the piles are causing differential settlement. that is what the sinking of the six piles showed us, it wasn't just a casing problem, it was a casing and pile ob


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