Construction and odor minimization efforts continue at the WRCRWA Treatment Plant.

Courtesy of the City of Eastvale

WRCRWA November Update

Construction and odor minimization efforts continue at the Western Riverside County Regional Wastewater Authority (WRCRWA) Treatment Plant. The WRCRWA team is committed to providing regular updates to the community about the project. In recent weeks, there has been an increase in concerns regarding odors from the facility and this post is an update on actions WRCRWA has implemented and are in the process of doing: 

1. Installation of tarp enclosure around solids loading structure. WRCRWA installed a tarp canopy system around the loading structure that was completed on Sept. 15. The purpose of the tarp canopy system is to enclose the loading structure where biosolids are loaded into trailers for offsite disposal. With the enclosure, the goal is to contain the odors and to have the air pass through passive carbon filters to reduce odors. However, WRCRWA staff is not satisfied with the effectiveness of the tarp system as originally designed and installed, and our team is in the process of making modifications to the system. Staff has met with the tarp contractor and modifications are in process and should be re-installed the week of Nov. 16.
2. Facility misters. Staff checks the misters on a weekly basis.  The misters are changed out as they fail. Our goal is to have 100 percent of the misters running 24/7. There is only one misting system at the facility and staff does not have the ability to turn sections on/off independently.
3. Centrifuge Building & Temporary Air Scrubber. With the expansion of the facility, three new Andritz Centrifuges are being installed to replace the aged Alfa Lavel Centrifuges installed in 1998. Centrifuges dewater the sludge coming out of the digesters prior to loading solids into trailers for offsite disposal. WRCRWA installed a rented temporary centrifuge and has operated it while the Alfa Lavel Centrifuges were removed and the new Andritz Centrifuges installed. The new Andritz units are now in start-up testing, which should be complete within 7 to 10 days.

   At the end of September a Duall rental air scrubber was installed to treat air within the Centrifuge Building. Although this air scrubber has been working continuously since the end of September, the Centrifuge Building has remained open during working hours so the contractors can install the new Andritz centrifuge units. Because the Centrifuge Building has been open during this installation process, effectiveness of the air scrubber has been diminished during the hours of 7 a.m. to 3:30 p.m. Once construction activities have wrapped up in the Centrifuge Building (anticipated within the next seven to 10 days), the building will remain closed (except for the occasional need to move equipment in/out) aiding in the effectiveness of the air scrubber. The following sequence of events will occur:

   1. Removal of the temporary centrifuge
   2. Relocation of the rental air scrubber where the temporary centrifuge was located
   3. Change out of air ducts from the centrifuge building to the relocated air scrubber
   4. Restart of the air scrubber
   5. Closure of the Centrifuge Building

Items a through e will take another few days, with goal to be complete prior to the Thanksgiving holiday. The result will be a totally enclosed Centrifuge Building with full air scrubbing of air within the Centrifuge Building prior to release to atmosphere.

1. Digester Operation. WRCRWA has successfully converted one of the two digesters to full aerobic process with the second unit acting as pretreatment sludge thickener using the facultative bacteria process. Both digesters are running well; the aerobic with a musty odor expected from an aerobic process and the facultative digester with a deep layer of clear water suppressing odors from it. Once the Andritz Centrifuges have gone through their start-up testing as explained above, WRCRWA staff will begin working towards operating the facility with one aerobic digester. This one digester operation is required to turn over the other digester to the contractor so it can be converted to anaerobic digestion, which will be a fully enclosed process. After the first digester is converted to anaerobic digestion and put into service, the second digester will be turned over to the contractor for conversion to anaerobic.   Staff is working closely with the contractor on the schedule for this effort and once final dates are determined that information will be shared on our website.
2. Recent manure smells. In recent weeks a property owner west of the WRCRWA facility has initiated the spreading of manure to fertilize a field used for crops. WRCRWA immediately notified the Air Quality Management District (AQMD), and an AQMD inspector visited our site and the surrounding area and confirmed that there were manure smells coming from the west. WRCRWA is in no manner attempting to shift responsibility; however, we want to report on recent activity in the area.

WRCRWA staff is diligently working to control odors at the facility. Significant effort is being made to systematically work through issues at the plant toward interim and permanent improvements. We appreciate your concerns and your patience during construction and are working as quickly as we can to implement all the improvements to control odors.

A tour of the plant is being scheduled for Saturday, Dec. 12, 10 to 11 a.m. We look forward to showing you all the things we have completed and the progress made that has been made.

For more information, contact WRCRWA Administrator Jeff Sims at 951.571.7220 or visit WRCRWA.org.