CF-Deforest SC-CS 861230 December 30, 1986
Mr. Frank Trando
City of Coppell
P.O. Box 478
Coppell Texas 75019 '
Re: Coppell Municipal Service Center
Dear Frank:
As you are aware, a major problem has surfaced regarding the
subsoil conditions under the paving. When we were originally
retained by the city to design the Service Center, we asked for
several documents including a current plat of the property and
,
a soJ. ls investigation of the site. The former City Manager
indicated that since the budget was already strained, he did not
wish to spend the necessary funds to perform either We were
.
told to proceed without them. We expressed a concern, but
proceeded as we were instructed.
Since we didn't have a soils analysis, Pete Hennessey had
requested that a city crew take a back-hoe to the site and dig a
hole approximately 6' deep so that we might check the soil unde'r
the surface. The hole was dug, and Hennessey obtained a bucket
full of the soil and delivered it to a testing lab for analysis.
The report listed the plasticity index (PI) at 3. We again
voiced our concern to the city staff, but were told to proceed.
When the plans were complete, we submitted them to the City for
review. The various City departments reviewed the plans and
issued a building permit on October 27 to proCeed with the
construction.
On November 17, you, Ed Powell, Steve Goram, and I met in the
City Hall Conference Room to discuss several concerns we shared
about the project. One of these concerns was the subsoil
condition. We discussed the low PI of the soil under the paving.
Mr. Powell asked what the paving design was. I stated that
generally, the drive has 6" concrete reinforced with #3 bars at
12 inches on center each way, and that the parking areas have 5"
concrete reinforced with #3 bars at 16" on center each way. Ed
said that he would fee] more comfortable with the stabilization,
but since to do so would add approximately approximately $
60,000 to an already strained budget, that he would approve
proceeding with the concrete paving as detailed. At that time,
there was no mention made of a City Ordinance requiring
stabilization.
The construction was begun, and the excavation was completed.
During the excavation and filling processes, Haynes & Hollon,
the City's Consulting Soils Engineers took numerous soil samples
of the various lifts of fill material. The lab tests on some of
these samples indicated extremely low to non existent PI
readings. When the written reports of these findings reached
Steve Morton, your new inspector, he voiced a concern that the
subsoils did not meet the requirements of the City Ordinance.
Last Nednesday, I was notified by Steve Goram about Mr.
Morton's concerns. (This was the first time we had heard of the
ordinance.)
I called you to discuss the ramifications. We decided to allow
the MDI to proceed with their formwork, but not to pour any
concrete without authorization. I wrote this instruction to MDI
in my letter dated December 24, 1986. I asked MDI to provide us
with a price quotation for providing the cement stabilization to
the paved areas. Their quotation was for $ 57,600 which I
relayed to you by phone on December 29.
Mr. Morton had Haynes & Hollon take new soil samples from the
areas scheduled to receive paving. These samples were taken
yesterday, December 29. The results were to be ready first thing
this morning. I called Haynes & Hollon at 9am this morning and
was told that some of the samples were still too wet this
morning to obtain accurate readings, but that two of the samples
yielded PI's of 3.5 and 4.5. I called Mr. Morton, who felt that
with these readings, the soil should receive stabilization. I
asked him to consult with you, and to Get back to me as soon as
possible.
Since I hadn't heard back from Mr. Morton by about llam this
morning, I went to the jobsite and found the MDI proceeding with
their formwork and reinforcing placement. I then proceeded to
City Hall to visit with you about the problem. When I arrived,
I found that you were out of your office all day.
Since we needed direction, I met with Mr. Bowman, and attempted
to fill him in on the situation. I explained that as I
understood it, we basically had three options. The first was to
allow MDI to pour the concrete (in apparent violation of a city
ordinance, but in keeping with Mr. Powell's directive); to allow
MDI to continue to set formwork and reinforcing (per my letter
of December 24) but risking further penalty costs (to the City)
of form and reinforcing removal if they later had to be removed
to perform the stabilization; or stopping MDI immediately
(realizing that MDI would be entitled to additional compensation
from the City of some $150 to $200 per day until a determination
is made. Mr. Bowman indicated that the next scheduled meeting of
the Council is on January 13. He asked that I instruct MDI to
stop the work immediately, and to provide a written request to
you so that consideration could be given for a special meeting
of the Council.
I immediately informed MDI of Mr. Bowman's directive. Upon
returning to my office, I received a call from Mr. Morton
explaining that he was then at the jobsite. He had spoken with
George Hollon of Haynes & Hollon who further explained the test
results.
Of the several samples taken, indeed only two had been dry
enough to complete the testing. Of those two, the lowest PI was
3.? and the other was 4.5. Mr. Hollon examined the remaining
samples and estimated that none were more sandy than the 3.?
sample, thus their PI should be above 4. These test results
should be available early tomorrow mor.n~ng.
Based upon the assumption that the readings would be Greater
than 4, Mr. Morton authorized MDI to schedule the pour for lOam
tomorrow. He explained to me that while the ordinance requires
stabilization of soils with PI's below 6, that his discretionary
powers allow him to vary as much as 2 points either way, and
that since readings above 4 would be within this range, he was
allowing the Contractor to proceed.
I hope that you realize that this letter is in no way intended
to be critical of any individual, but only to serve as
documentation of a very confusing sequence of events. The fact
that we did not have a soils analysis from the beginning Greatly
compounded the problem.
We were the architects on the new facility for Shake & Shingle
Supply at 200 E. Belt Line Rd. This facility was completed
during May of 1986. Their paving subgrade was not stabilized. We
purchased a Coppell Subdivision Ordinance prior to designinG
Shake & Shingle. We can find no reference to this requirement in
our copy.
On the assumption that the ordinance was adopted subsequent to
the printing of our copy, why wasn't the problem addressed
during the review of our plans and specifications for the
building permit? While admittedly Mr. Morton has information
available to him now that was not available to Mr. Powell, why
wasn't the issue City Ordinance addressed earlier?
AGain, hopefully we can al/ learn from this experience. The lack
of adequate information up front and the timing of the red flag
could have cost all of us.
Richard A. Calvert, AIA
cc: Steve Goram
~eve Morton
Vivyon Bowman
Frank Pieschel
Pete Hennessey