Sent to my colleagues on the Council, 7/27/09:
I have reviewed the information sent to our Office from Portland Water Bureau titled, "Response to Portland City Council Questions on Bull Run Treatment Presentations".
I appreciate Commissioner Leonard and Director David Shaff for providing the information and for scheduling a hearing to discuss the preferred treatment option should efforts to avoid additional treatment for cryptosporidium fail.
I have some further observations and questions to clarify information in the Response binder.
1. A Revised Total Coliform rule is pending (page 2 of report), with the Proposal from the EPA expected in 2010 and the Final Rule in 2012.
While the new rule will be focused on system delivery risks, treatment of surface water for E. coli may be required by the EPA in the future.
Appendix D in the binder states, UV is "highly effective" against E. coli.
Appendix D states direct filtration is "not effective" against E. coli.
- Why is the City planning to move forward with filtration, if it does not address a potential future regulation of E. coli?
2. Additional protection against microorganisms over Chlorine treatment
The report states on page 4:
"UV would not provide any additional treatment over current treatment practices. Filtration would provide additional benefit for entamoeba histolytica, hepatitis A, salmonella, and cyanotoxins".
This statement is contradicted by the data you provided.
Appendix D states filtration is "not effective" for Hepatitis A.
Appendix D states UV is "highly effective" for Hepatitis A.
Appendix D states filtration has "no effect" on Salmonella, and
Appendix D states UV has a "minimal effect" on Salmonella.
The Term "minimal" is listed for both UV and filtration for cryptosporidium, so apparently "minimal" is acceptable.
Appendix D. Does Not list Histolytica and cyanotoxins
Our research indicates that Cyanotoxins can be destroyed by UV depending upon the organic load in the water. Filtration removes the cells but not necessarily the toxins stored in the cells.
Our research indicates that Entamoeba hystolica is a human intestinal parasite that causes amoebic colitis and liver abscesses. Humans are exposed to the cycts through ingestion of food or water contaminated with human fecal material. Filtration of municipal water removes the parasite.
- Why do you state, "PWB is confident that adding another barrier, such as filtration, will provide more protection against these microorganisms than does the current treatment regime", when the information provided states that it does not?
Appendix D lists 20 microorganisms
Chlorine is listed as effective or minimally effective against 12 of them
(4 effective, 8 minimally effective).
Of the 16 microorganisms listed where chlorine is not effective or minimally effective, filtration is effective against 4 (1 highly effective, 3 minimally effective).
Of the 16 microorganisms listed where chlorine is not effective or minimally effective, UV is effective against 9 (1 highly effective, 3 effective, 5 minimally effective).
- Using your data, UV is better than twice as effective than filtration against microorganisms not treated by chlorine. Why then are you recommending filtration over UV for microorganism protection?
OF ALL LISTED CONTAMINANTS
5 of 55 contaminants are not treated by chlorine + filtration, plus 8 with no data. The 5 where neither chlorine nor filtration is listed as even minimally effective: staphylococcal enterotoxin, T-2 mycotoxin, cacodylic acid, carbofuran, norovirus.
2 of 55 contaminants are not treated by chlorine + UV - Anatoxin A, Toxoplasma (no data on filtration), plus 24 with no data.
- When No data is listed it should in turn not be counted … then according to this data, UV would be the best form of treatment. Given this data, why does your bar chart on page 8 show filtration to be more effective than UV?
3. Carbon Footprint of Filtration facility
- "What is the solid waste disposal process for a filtration facility?", Question 4.4 on page 12, is not answered. The text discusses how to get the solids out of the backwash water. Commissioner Saltzman asked what happens to the waste solids after removal. What is the process for removal and disposal? What is the carbon footprint of the waste disposal process?
- What will be the cost of pumping the water through the filters vs. the cost of powering a UV light?
4. Columbia South Shore Well Field
Page 16 states that the well field will be used once in four years with the filtration system, vs. once in three years currently.
- Why is it worth spending $385 million to reduce well field use by only 25%?
5. The current rate projection for filtration in FY 2014-5 is 13-14%, per page 25.
6. Annual Opperations and Maintenance cost for filtration
The report states (p. 26) that Operations and Maintenance is $1.3 million more for filtration than for UV . Savings from not pumping the wellfield are $209,000, plus estimated savings from reduced turbidity at $275,000 leading to total quantifiable annual savings of filtration at $484,000.
Even taking into account estimated savings, filtration is $800,000 per year more in annual operating costs compared with UV.
- Why is filtration worth spending more in annual costs as well as in construction?
7. The PURB Water Sub-team report
This group recommends, "Select the crypto Treatment Technique with the best long term return for water customers regarding all issues facing the Water Bureau. Filtration should not be ruled out as a treatment option because Bull Run watershed has strong legal and legislative protections of its pristine state".
I have heard the statement. "The PURB supports filtration."
- Is there additional written advice from the full PURB which is not in the binder, that states positive support for filtration rather than it "should not be ruled out"?
8. Additional potential contaminants of concern
Appendix C states the only microbial contaminants still being considered for regulation are caliciviruses, cyanobacteria, and Helicobacter pylori.
Appendix D does not list any of these contaminants.
Our Research indicates
Helicobacter pylori
- bacterium that infects the human stomach and upper gastrointestinal tract
- Class I carcinogen for stomach cancer
- waterborne pathogen that has been detected in drinking water
- UV readily inactivated at levels typically used in treatment plants
Our Research indicates
Caliciviruse genus “Norwalk-like viruses” ---
- causes acute gastroenteritis throughout the world
- Is the second most common cause of viral gastroenteritis in children following rotavirus
- Is listed on EPA drinking Water Contaminant Candidate List
- Inactivated by UV.
Our Research indicates
Cyanobacteria
- Is a photosynthetic bacteria
- That some cyanobacteria produce poisons, hepatotoxins and neurotoxins that are stored in the cells
- That microcystin: a cell bound toxin produced by the cyanobacterium Microcystis aeruginosa is the most common of cyanobacterial toxins found in water and is released into water by dying and decaying cells
- filtration removes cells but not necessarily the toxins stored in the cells
- activated charcoal, nonofiltration membranes chlorination and ozonation work
- UV effectiveness depends on the organic load in the water.
It appears that with these microbial contaminants, U.V. is an effective treatment, and filtration may or may not be useful against them.
- Debt service for the Water Filter System vs. UV – While this was not a part of the Report, OMF figures on Revenue Bonds for these projects show that debt service on $100 million in revenue bonds (UV) tops out at $180 million. Debt Service on $385 million in revenue bonds (filtration) tops out on at almost $700 million. – approximately 3.8 x more expensive.
CONCLUSION: Based on my review of the information in the binder and for the reasons stated below, UV seems to be the better choice for treating Bull Run water, if we are unable to obtain relief in Congress/EPA.
* UV costs over $200 million less for construction
* UV treats more microorganisms, including E. coli which is next up for regulatory measures, and it is effective against viruses which filtration is not
* UV has lower carbon footprint due to need to truck and dispose of waste from filtration plant and use of pump power over gravity flow system in UV.
* UV has $800,000 lower annual O&M cost
* UV does not affect taste
* UV protects the "forest to faucet" branding
* The cost/benefit ratio of what filtration provides vs UV appears to indicate cost and effectiveness of filtration does not outweigh long term, operation, maintenance and effectiveness of a UV system.
I support the Resolution on Wednesday's Agenda, with the exception of its identification of filtration as the preferred option if we need to install more treatment. I plan to propose an amendment substituting "ultraviolet" for "filtration" as the backup treatment plan if we are unable to obtain a variance from the Environmental Protection Agency.
