From: "Osalbo, Faustino Jun" <email@example.com>
Date: May 10, 2005 5:17:01 PM PDT
To: 'Mark Brest van Kempen' <firstname.lastname@example.org>, 'Barbara Sutherland ' <IMCEAMAILTO-bsutherland+40ucdavis+2Eedu@oaklandnet.com>
Cc: "Brooks, Desley" <DBrooks@oaklandnet.com>, "Nadel, Nancy" <NNadel@oaklandnet.com>, "Uzegbu, Marcel" <MUzegbu@oaklandnet.com>, "Estes, Lesley" <email@example.com>, "Schwarz, Alison" <firstname.lastname@example.org>, "'email@example.com'" <firstname.lastname@example.org>, "'email@example.com'" <firstname.lastname@example.org>, "'email@example.com'" <firstname.lastname@example.org>, "Neary, Mike" <email@example.com>, "'Friendsof2Creeks@yahoogroups.com'" <Friendsof2Creeks@yahoogroups.com>, Office of the Mayor <OfficeoftheMayor@oaklandnet.com>, "'firstname.lastname@example.org'" <email@example.com>, "'firstname.lastname@example.org'" <email@example.com>, "Ward, Ron (PWA)" <firstname.lastname@example.org>, "Lau, David W" <email@example.com>, "Sweiss, Fuad" <firstname.lastname@example.org>, "'email@example.com'" <firstname.lastname@example.org>, "'email@example.com'" <firstname.lastname@example.org>, "Madison, William" <email@example.com>
Subject: Chimes Creek turbidity and pumping
Mark & Barbara,
Attached is an email response from DeSilva Gates Construction investigating turbid water during the rain.
Please note that when it rains and there is increase flow at Chimes Creek, the flow in Chimes Creek is turbid, as confirmed many times by Mark Brest van Kempen. This has been the case last Wednesday, May 4th when rain fell in the afternoon; Thursday and Friday, May 5th & 6th. Rain continued sporadically Sunday and Monday.
I am confirming what transpired last Friday as reported by DeSilva Gates in the email: NTU reading at the pond was 7 NTU and DeSilva Gates Construction was granted permission to dump the clean water into the City storm system.
I verified the output of the subdrain pipes located at
inlet: the subdrain water was clean. There was negligible water flow at the other three locations where subdrain flows and v-ditches are directly connected into the storm system. I concluded that there is no dirty water leaving the Leona Quarry.
Senior Construction Inspector
From: Charley Lella [mailto:firstname.lastname@example.org]
Sent: Tuesday, May 10, 2005 3:06 PM
To: Jun Osalbo (E-mail)
Cc: Kent Peyton; Peter Helseth; David Chapman; Jim Summers; Ron Rinehart
Subject: FW: [Friendsof2Creeks] Chimes Creek turbidity and pumping
As you are aware during every rain event in this area the water in ChimesCreek becomes cloudy. However, as you are also aware the source of the cloudy water has been proven in the past to be from other sources such as aresult of runoff and bank erosion, not from the Leona Quarry site. DeSilvaGates Construction has complied with all RWQCB standards and has implemented additional SWPPP measures to protect this site.
Because the weatherman was forecasting rain for Sunday and Monday, while we had the opportunity, in between storms, as a preventative measure we initiated our detention basin maintenance program by lowering the water level in the basin Friday morning. Lowering the water was accomplished by first sampling and testing the detention basin water for its turbidity. The test results of the water sample gave us a reading of 7 ntu's verified by you. As you are aware, 7 ntu's is well below the 50 ntu threshold to releasewater directly into the storm drain system. As a result of the positive test results, and the City's approval, we then released, i.e. pumped, water directly into the storm drain system for less than 4 hours.
For those who are interested I would like to point out the mis-information and mis-representation of the facts that are being passed on by others below. I am certainly not an expert and do not claim to be one in these matters, but, I do have over 30 years of construction experience and I can tell you these facts-
"They are pumping at 350 cfm. For the layman that means little but ittranslates to:
2618 gallons every minute or:
157,080 gallons every hour or:
1,256,640 gallons for ONE 8 hour day."
Therefore this project during construction is adding over 1.25 milliongallons of water EVERY DAY into Chimes Creek when pumping occurs whichhas been pretty much daily throughout the rainy season (This alsoassumes thatthere is no pumping at night)."
Since January 1st we have released water only 40 of the 120 days from Jan.1st to the end of April. On all but a handful of these days, we pumped onlya portion of the work day, not all of the (8 hr) work day. Also for thelayman, the capacity of our system is not 350 CFM it has averaged only 48.6CFM for the 40 days, we simply do not pump 1,256,640 gallons every day as indicated by others. Our detention/filtration system is not designed for, and the Chimes Creek basin could not handle, the 350 CFM that is referenced above and below. I would like to add an important point which I believe is being over looked by every one. During a rain event (dirty) surface water collected on site is sent to our detention (holding) pond and then it is pumped through our filtration plant for "cleaning". The filtered water then leaves the site clean, i.e., well below the allowable turbidity standards for releasing water directly into the existing storm drain system.
"Thank you very much for agreeing to look into the very turbid quarry-colored water that has been following the recent rain showers"
In Barbara Sutherland's E-mail of May 6, 2005 Barbara refers to "sinister" looking water that is running through
. I would agree that it is "sinister" looking, however, the origin of this "sinister" looking water is not from the Leona Quarry Project via Chimes Creek. Chimes Creek empties into
down stream from the College near MacArthur and therefore does not impact any of the water flowing through the college. The origin of the "quarry-colored" water (see attachments) is most likely from the old Leona Mine located off
. Near its origin, the water in the creek is orange colored, but as the water travels over rocks, falls and check dams it aerated loosing most, not all, of its color.
With the interest that is being expressed, I would think that one would look into this circumstance; it seems to be a viable concern with the neighbors in the
1) Sub drain water thatflows directly from storm drains into Chimes Creek
In a rain storm the subdrains alone now seem to give off as much or even more water than the total run off before construction since this system now has the Ridgemont drainage tied directly in to it.
No more water leaves the site than enters the site either through the subdrains or the surface water. Only a portion of the subdrain water enters the storm drain system directly, the balance of the system flows to thedetention pond. As you know by our sampling & testing of the water from Ridgemont, the water that leaves the site via our subdrain system is"cleaner" than when it entered. The Ridgemont water and all othersub-surface water that is collected by the system is filtered naturally through the soil and also by way of the subdrain filtering process, the full length of the system. What is captured is channeled through the subdrainpipe, not the storm drain system, and outlets in a storm drain pipe approximately 10-ft from the catch basin on
, it then enters the storm drain system, as does water from other sources, and eventually outlets into Chimes Creek.
If you have any further questions or need any additional pictures please feel free to contact our Project Office at 510.777.9642.
From: Osalbo, Faustino Jun [mailto:email@example.com]
Sent: Friday, May 06, 2005 12:00 PM
To: Charley Lella
Cc: Peter Helseth; Kent Peyton
Subject: FW: [Friendsof2Creeks] Chimes Creek turbidity and pumping
See attached. Could you get me some comments.