The URL can be used to link to this page

Home My WebLink About06.a.3) General Manager Announcements6 0&0 3 ) Agenda Item 6.a.3) Board Meeting of September 16, 2010 Written Announcements: Board Related Update a) Board Member Lucey's Retirement Celebration Board Member Jerry Lucey will officially retire from the Board on December 3, 2010. He will have a retirement celebration on Wednesday, December 1, 2010, at Jack's Restaurant and Bar (formerly The Left Bank Restaurant) located at 60 Crescent Drive in Pleasant Hill. There will be a no host bar from 6:30 p.m. to 7:30 p.m., with dinner being served at 7:30 p.m. The cost is $35 per person. Flyers will be distributed soon. Personnel Update b) Senior Plant Operator Chris Goward's Status Senior Plant Operator Chris Goward has returned to work after six months off due to a vehicle accident. He is currently working four hours per day in Plant Operations filling a vacant Administrative Assistant position. Mr. Goward has expressed interest in receiving further training in other areas. General Updates c) Hall Drive Sewer Renovations Update The Board expressed interest in an update for the Hall Drive Sewer Renovations (Phase 213), DP 5932. Attached is an informational memo. d) BMP Permit Seminars Scheduled for October Staff has scheduled two Best Management Practices (BMP) Permit Seminars on October 5 and 20, 2010, for facilities that have recently been issued a BMP Permit (e.g. vehicle service, car washes, and machine shops). The seminars are condensed versions of the Industrial User (IU) Academies that have been held for the more significant permitted dischargers; they are scheduled for 4 hours including an optional plant tour. Invitations were sent to 257 businesses permitted under the BMP Permit Program over the last year. e) Eight Comment Letters Received on Draft EIR for DA 168C — Alhambra Valley As of the close of the public comment period on September 3, 2010, the District has received eight letters commenting on the DA 168C — Alhambra Valley Draft EIR. Four letters came from public agencies and four from local property owners. DA 168C proposes annexation of nine residential parcels that are outside the County's Urban Limit Line. Of the four public agency letters, the Contra Costa County Department of Conservation and Development questions the need for sewer service and the report's interpretation of County land use policies; the National Park Service asserts that more analysis is needed on the impact of possible future housing developments on the adjacent lands of the Mt. Wanda portion of the John Muir National Historic Site; the Contra Costa Water District concurs with the report's contents regarding water service; and the State Clearinghouse acknowledges that no State agencies have submitted comments on the document. Of the four property owner letters, two are from Oakbridge Lane (outside the project area) objecting to the annexation of the nine, nearby properties, particularly one that has access on Oakbridge Lane and is projected to be developed with two residences. Another letter is from a Gordon Way property owner /attorney who claims inadequacies concerning the project description, the John National Historic Site, the impact analysis, consistency with County land use policies, the Initial Study, and the alternatives analysis. The final letter is from the owner of the largest parcel in the project area; he supports the Draft EIR's conclusions and the project. Staff will be working with the District Counsel's office to prepare responses to these comments and any needed EIR text changes for inclusion in the Final EIR. Prior to setting a new public hearing date, staff will report back to the Board of Directors on the Final EIR's progress. Because of the complexity of some of the issues raised, the public hearing set last meeting is proposed by staff to be rescinded and will be reset for a future date. Central Contra Costa Sanitary District September 9, 2010 TO: HONORABLE BOARD OF DIRECTORS VIA: JAMES M. KELLY, GENERAL MANAGER ANNE. FARRELL, DIRECTOR OF ENGINE ING FROM: TAD J. PILECKI, CAPITAL PROJECTS DIVISION MANAGER (!T� SUBJECT: SEWER LATERAL DESIGN ERROR AT 226 HALL DRIVE, HALL DRIVE SEWER RENOVATIONS, PHASE 2B, DP 5932 At the August 5, 2010 Board meeting, the General Manager informed the Board of Directors of a change order issued due to an error in the information shown on the project plans. After installing approximately 380 feet of sewer main at the proper slope, staff discovered that for 226 Hall Drive, the lateral elevation at the house tie -in was approximately one foot lower than shown on the construction plans and therefore, due to the tight tolerances on this particular main realignment, the home could not drain by gravity to the new sewer main. The timeliest solution was to re- install the new sewer main at a lower elevation to allow the lateral to drain by gravity. Because the elevation error was not the fault of the contractor, the re- installation of the sewer main was done at District expense. District staff have designed /constructed a number of very complex renovation projects over the last ten years in neighborhoods where there are few, if any, record drawings, and property owners have made many permitted and un- permitted changes to their sewer laterals. Fortunately, an elevation discrepancy of this magnitude has not occurred previously and any minor elevation variations we have experienced have been accommodated without project impacts. Staff was very concerned about the cost impacts to the District from this particular error, and conducted an extensive review of the design process and the design documents to identify practices that could be improved to reduce the likelihood of such an error occurring in the future. The investigation showed that there were actually two errors that, when combined, resulted in an elevation difference that was outside the tolerances for gravity connection to the newly installed sewer main. The first error occurred when the surveying team checked the invert of the house lateral. This particular home had two clean outs on its lateral and the crew assumed that the cleanout furthest from the home would have the lowest invert elevation, because that would be logical in order to flow to the sewer by gravity. However, the cleanout they checked was offset from the lateral and the invert elevation where the cleanout was located was higher than the actual lateral. When it became time to connect the house lateral, it was discovered that a cleanout much NAENVRSEC \Position Papers \Farrell\2010 \Hall Drive DP 5932 Memo 9- 9- 10.doc they eheGked .w offset from the I-+4 al a d th r t I a' where t. l loser to the home and not checked by the survey crew, had a lower invert elevation, and that the lateral was lower than shown on the contract drawings. Because this home is on a slab foundation, there was no way to visually check the invert elevation of the lateral during the design process. The second error was due to an engineer incorrectly transcribing an elevation from a calculation sheet to the contract drawings. The detailed design check did not pick up this transcription error and the actual elevation difference was a few inches. However, when these two errors were summed, the total difference in elevation was about one foot, and was enough to result in the house lateral not draining by gravity to the new sewer main. Staff conducted an investigation reviewing the design process. The recommended changes to the design and construction process are discussed below: • Design Changed Procedures: For homes on a concrete slab, such that the lateral inverts cannot be visually verified, the designer will use other methods to confirm the lateral elevation. These methods may include checking all available cleanouts, checking any existing drawings, and using other locating techniques, such as potholing or TV inspection, as appropriate. In addition, the person responsible for checking the design calculations will check that key elevations have been properly transcribed from the calculation sheets to the design drawings. • Construction Changed Procedure: When existing laterals are re- routed or the elevation of the replacement main is at a higher elevation than the main being replaced, the invert elevation of the connecting laterals must be confirmed in the field (pothole if necessary) prior to installing the sewer main. If any discrepancies are found, it will then be possible to do some re- design without incurring the cost of re- installing the sewer main. In the future these new procedures will be followed during design and construction of sewer main renovation projects to attempt to avoid the re- occurrence of the error experienced at 226 Hall Drive. C: \DOCUME- 1 \eboehme \LOCALS- 1 \Temp\XPgrpwise \Hall Drive DP 5932 Memo 9 -9 -10 Strikeout_1.doc