Document DD93nXzw0LpvGmkxkzEx2J5Y5

00080362 GRACE TO: W. J. McCaig FROM: R. J. Geiger Zonolite ^ Construction Products Division DATE: July 12, 1983 SUBJECT: May & June 1983 Pollution Control Report cc: L. A. Vazquez During J*&y and June, 230 sanples were collected and analyzed for fiber. A great deal of our effort was spent on trying to describe sources of emission in the mill area. We also had additional demands on lab time as we counted 40 slides by the discriminatory method to verify with J. Yang the validity of this method. As you know, we will change our lab analysis beginning in June' to reflect this method. Our preliminary data suggests we will see a 50% reduction in overall fiber levels. As you can see by the attached data, we have programmed the Apple III to calculate and print the individual sample results. We are now working on writing a continuation cf this program to calculate a monthly summary. Hopefully, this will allow quicker and more meaningful data manipulation. The average of the 35 personnel sarples collected during this period was 0.43 F/CC. Although no violations of the 2.0 F/CC standard were noted, several problem areas as discussed below were evident as they relate to our half fiber goal. 1) Upper floor operator and others doing ''wet" work in this area. This problem is believed to be partially due to the water borne fiber deposited on the filter. Besides working on the general mill fiber problems, we have tested a "spray booth" with various water types. 2) The popcorn wagon assay job has been moved to the mill lab area in an attempt to solve this problem. We will monitor his new job this month. HILL FIBER REDUCTION TEST WORK Water Related Work. An enclosure containing a single spray nozzle was fabricated and air samples collected with different water types. Three splits were separately analyzed for fibers/unit water volume, total solids and turbidity. Our goal is to relate water borne fiber to air borne fiber. A report should be available in the near future. Mill Tests. Samples were collected after a series of the SX20 feed prep screens were equipped with modified, extended spray nozzles. As expected, these tests were inconclusive. This type test work has been shifted to the 5th floor rock circuit screen area. Following enclosure with plastic, the fiber level increased slightly from 1.08 F/CC (unenclosed) co 1.26 F/CC afcer enclosure. Tests will continue in this area. 15128981 GRACE TO: W. J. McCaig FROM: Randy Geiger 060S0263 Zonoiite Construction Products Division July 12, 1983 2- - Tails Skid. This area is serving as model for mill test work. This area was sampled as is, after cleanup and with the sand separator simp covered. We do not yet have data with the sump covered, but saw a slight, inconclusive drop in concentration following cleanup of 0.66 to 0.59 F/CC. Of particular interest was the high fiber levels witnessed cn each sample located directly above the return water sump. These samples averaged 1.31 F/CC as compared to 0.49 F/CC for the remainder of the samples. MILL GENERAL We are conducting sampling during start-up periods in the mill to determine how fast fiber levels build in the mill. A sample set collected during downtime seemed to indicate a drastic rise in fiber levels which corresponded to feed introduction to the mill. We have no data yet on these samples. R. J. GEIGER: ch 15128982