Document YYgo871YbmLNOMRdV2o96Bz8

'h Vi /' iNOUSTfllAL ZSIVISlCNJ NALCO CHEMICAL COMPANY ISO N. MICHIGAN AVENUE o CHICAGO, ILLlNCiS S BO", c A=I=A 312-322-1200 September 25, 1972 PLAINTIFF'S EXHIBI T Public Service Co. of Colorado P. 0. Box 340 Denver, Colorado 80201 Attention: Mr. Pat >teCarter Superintendent, Cherokee Plant Dear Mr. McCarter: Attached is the analysis of the material removed from the number 3 secondary superheat tube. You will note that the constituents are all metals from the tube itself. The material is exfoliation of the superheater tubes. This isi com mon in high pressure utilities. The oroblem is basically metallur gical in nature. There is nothing in the way of water treatment that would helo. We can discuss this during our next visit. Yours very truly, Don Hughes District Reoreseh'tative 3CH:ms cc: Mr. Ray Dudley, Asst. Supt. Mr. Carl Yarcho, Supt. of Plants Mr. A. F. Baal, Chief Betterments Engr. Mr. John Groothuis Mrs. Judy Hughes Mr. A. G. Keleher ~ Z \A. .\i C wsa. lO'.CRAZC 3Z3`G a AScA 3C3'76C-337 WA DO0244 N NALCO REPORT OF DEPOSIT ANALYSIS From PUBLIC SERV. CO. CF CCLC. - CHEROKEE DENVER, CGLQRACC Sample Marked REMOVED FRO* UNIT 3 SECCNCARY SUPERHEAT LABORATORY ANALYSIS (per cent) Analysis No. Sampling Date Date Sample Rcc'd A 3 5 596 9/ L/72 9/ 7/70 CALCULATED COMBINATIONS (pr cant) Lott at dull red hoot......................................... 0. Lott on Ignition............................................. 2. Silica [at SiO,|................................................... ! Silica (at SiOi]................................................ L. Photphoreut Pentoxide (at P,0,J................. 0 Porrlc Oxido (at Fe,0,|.................................... 96. Sulfur Trioxido [at SOt]................................... 0* Calcium Oxido [at CaO|.................................. 0. Magnotium Oxido (at MgO|.......................... 0. Alumina [at Al,0,[.......................................... I* Carbon Dioxido [at CO,|................................. 0. Sodium Oxido [at NaiO]................................. CHROMIC OXIDE 0. 3. GAIN ON IGNITION U Alumina [at AliOi)....................................... I. Iron Oxide [at FeiOi].................................... C. Magnetic Iron Oxido [at Fe,0l. . . .............. .............Batic Calcium Photphate [at Ca,o (PO)e<OH),[ Magnotium Photphate [at Mg, (POtJi Mg (OH),l..................... 9 2. 0. C. Calcium Carbonate [at CaCO,|.................... Calcium Silicate [at 5CaSiO, H,0|................................... Magnotium Silicato [at 3MgO 2SiO, 2H,Ol..................... Magnotium Hydroxide [a. Mg (OH),|............................................. 0. 0. 0. 0. Sodium Oxido [at Na,0]............................... Q . CHROMIC OXIDE 3. I Carbon Tetrachloride Extractabl NALCO CHEMICAL COMPANY ISO N. MICHIGAN AVENUE CHICAGO. ILLINOIS 60801 WAD00245 I I I-BOILER UNIT - MAINTENANCE WAD00243