CORRESPONDENCE_2005-2006 - Laserfiche WebLink

Home Browse Search

Ms. Molly White -2- CHANGE IN BARRIER METHOD AND ADDITIONAL DOCUMENTATION FOR FOOTHILL LANDFILL SITE IMPROVEMENT PROJECT, CAO R5-2004-0706 2. With RWQCB approval of the submittals described in #1, we will: a. Construct the ET test section in 2005. The test section 4egetation will include advanced growth, to approximate performance after vegetation is established. b. Revise Module "I" ET cap soil specifications accordingly. It is also our understanding that. we will continue to operate the ET Test Section through 2010 (5 years). After completion of the 5 years of testing, we will submit final assessment reports to RWQCB. RWQCB's review of this report will be the basis for RWQCB staff to either approve the ET cover design, or request modification of that design. Such design revisions will likely require additional work on the seven -acre ET cap installed on top of Module "I" in the Foothill Landfill Site Improvement Project, MODULE Ul SIDE SLOPE BARRIER We will submit the redesign of the Module "I"/1 side slope barriez to conform to the directives of your email of October 21, 2005, requiring a composite liner with HDPE gemembrane over the refuse of Module "I". This submittal will include: a. Features to allow the escape of landfill gas. We may submit this detail prior to other items. b. Selected details, revised to show the use of the HDPE membrane. c. CQA Plan text reflecting the inspection and certification of this new component of the project. We anticipate this will be submitted in November. We hope that this submittal can be reviewed within two weeks of receipt. Please let us know if our understanding is correct, or please call to discus any items that require clarification. If our understanding and schedule are acceptable to Board staff, we will proceed with this work immediately. And, if this meets with your approval, we would appreciate acknowledgement in writing within two weeks. This will allow us to proceed before we receive a revised CAO. IMPACT TO SCHEDULE With all due respect, we disagree that the WDRs were intended to apply to the barrier between Module "I" and 1. We believe that recognition of this, and of the significant concern for ballooning under a HDPE liner placed over refuse prompted previous RWQCB staff to approve the barrier first submitted in the Project Design Report (August 2004). Since that time, we adhered to the design decisions trade and approved by Board staff, and made a conscientious effort to confirm the design concept in the design details developed over the next year. We were therefore surprised to receive a