From: "Keith Lichten" <firstname.lastname@example.org>
Date: Thu, 28 Oct 2004 14:45:31 -0700
Cc: "Dale Bowyer" <DCB@rb2.swrcb.ca.gov>, "Laurie Taul"
Subject: Re: Leona Quarry
Thank you for your email. We do look both at construction-stage impacts and post-construction impacts (i.e., once a project is complete and operating). We submitted a CEQA comment letter (or letters) for this project focused on that issue.
The City's permit with us requires them to ensure that appropriate "post-construction" controls are implemented in projects. They have significant flexibility in doing that. Recently, a stricter permit standard was implemented (that still retains some flexibility), but this project's initial approvals came before that stricter standard came into force. For this reason, and because the project does not have an individual discharge permit from us, it is not clear to me that it would be consistent for us to look more closely at them, when they appear to be implementing a number of controls already that will treat runoff from most of the project.
I would be happy to talk with you more on this, as I think Chiye has made the point that post-construction measures required in the Conditions of Approval may not appear in the current development proposal. However, given that the Council committee meeting's discussion focused on construction-stage controls, and that "adequate" (under the permit) controls aren't necessarily absent from this project, this isn't necessarily a line we can vigorously pursue.
As an aside, for a control to treat about 80-90% of average annual runoff in this part of the Bay Area, it must treat the runoff resulting from the 1-inch storm (approximately). For a detention basin, treatment processes include settling, infiltration of stormwater (and adsorption of pollutants to soil particles), and biodegradation of organic pollutants, in addition to degradation around the roots and plant uptake. For better or for worse, the current current regulatory approach under the Clean Water Act is to reduce pollutants to the maximum extent practicable from new and redevelopment projects. In practice, this means limiting the increase of pollutants associated with new impervious surfaces, rather than reducing the total level discharged.
Also, it is my understanding that the project, working with the City and with Alameda County Flood Control, also is designed to minimized changes in the hydrograph that could increase downstream erosion. This is a permit requirement that does not phase in until several years from now, so the project looks good for having addressed it, at least to some extent, now.
-Keith H. Lichten, P.E.
Acting Section Leader
San Francisco Bay Regional Water Quality Control Board
1515 Clay Street, Suite 1400
Oakland, CA 94612
(510) 622-2380 direct
(510) 622-2460 fax
Mark Brest van Kempen <email@example.com> 10/28/04 12:17PM >>>
Thank you for inspecting the Leona Quarry site and speaking at the meeting. Its pretty clear to me that they listen to you much better than they listen to the community. I wanted to hear about your findings and also point out something that Im very concerned about and may not be clear at first glance at the site:
The detention pond is the only treatment for storm drain run off before it enters Chimes Creek. Keep in mind that this project will introduce some 1000 cars into the watershed and an equal number of people fertilizing their lawns, washing their cars etc etc.
The idea for the treatment in the detention pond is to have a wetland area planted between the 72" pipe that feeds the pond and the outfall structure. The contaminated water is supposed to percolate through this wetland area thus leaching out contaminates before leaving the detention pond. As you probably know, in this type of system, the cleansing process takes place by bacteria in the plants roots.
This first rain has shown that this treatment area will be inundated below 3-5 feet of water during the first storm rendering the system wholly ineffective for lighter than water contaminates such as oil which will pass directly into the Creek.
The introduction of oil into Chimes Creek by an inadequately designed storm system I believe should be of great concern to the State.
Now that the City is asking the State for recommendations on the site before approving the final map, I would urge you to recommend that ALL run off on the site be filtered through vegatative swales BEFORE it enters the storm drain system. This will also help to reduce volume and velocity of run off which are also crucial factors in the success of this site.
Please let me know what your findings were.
Mark Brest van Kempen
3835 Delmont Ave
Oakland CA 94605
510 568 6889