Document 5DB5aazKbNN1n8EKO9YbrGOgz

Interoffice Communication To Steve Ashby From Too Grumbles Date April 22, 1981 Subject DEREGULATION OF REGULATED AREAS As ve have discussed below are the factors to be considered in deregulating areas. 1. Personnel monitoring on operators with job duties in the areas of concern. 2. Operator duties in the designated area a. time spent in area b. duties performed in the area c. other time necessary in the area for non-specific duties. 3. Area monitoring for designated area. 4. Changes in equipment, processes, etc. in the area related to the presence and control of the chemical or agents of concern. 5. Proximity of the area to other potential sources. Enclosed are several examples of the deregulation process accomplished at the VCM plant. These serve as a good example for the way a combination of the above factors should be used. Once you have gathered the available data we can discuss further the written determination. Let me know if you need further information at this time. ajo Enclosure CCR 000000232 Regulated Area =4 VCM Loading Pumps Point ?2 Offsite Monitor ppm VCM - Monthly Avg. all Values No. Days Over 1 ppm VCM Avg. of Daily Values Over 1 ppm VCM No. of Hourly Avg. Over 1 ppm VCM % Time Hourly Avg. Over 1 ppm VCM August .68 3 2.68 83 11.2 September 1 .04 10 1.88 171 25.4 The data from regulated area.#2 - loading rack - must be -evaluated keeping in mind the number of tank car shipments. During August, eighty-nine (89) tank cars were loaded while two hundred seven (207) tank cars were loaded in September. Since an average number of tank car loadings occurred in September, the analytical data must realistically be viewed as representing normal conditions. Assuming this to be the case, the data must indicate that vinyl exposure occurs during the duration of the loading and not just while the loading line is being connected. This conclusion is based on the percentage of hourly averages exceeding one ppm and the tendency for the values over one ppm to be consecutive. Eleven personnel dosimeter testings were conducted during August and September, not one exceeded the one ppm exposure. This seems contradictory based on the percentage of time the area monitors were over one ppm. The date each dosimeter testing was conducted was checked against the daily average for the regulated area sampling points. Of the eleven, three personnel testings were conducted while the average concentration of a sampling point within the loading rack regulated area exceeded one ppm VCM. Of these three occasions, one testing had one point above one ppm, a second had two and the third had all four. The average concentration at the sampling point within the reaulated area above one ppm for the above mentioned testing were (1) 1.30, (2) 1.49, 1.07 and (3) 1.55, 1.02, 1.12, 1.03. Although the 8 hour personnel dosimeter data indicates that vinyl exposure is not a problem and it may not be due to the mobility of the Pumper/Loader, the fixed point monitoring data definitely indicates a problem exists in the work area not only for prolonged worker exposure but.also for the fifteen minute 5 ppm ceiling limit. During August, twenty-five hourly averages exceeded 5 ppm while this limit was exceeded eighty-five times during September. Until the corrective action step aimed at reducing the vinyl exposure to the pumper/loader working within the tank car dome is completed satisfactorily, I do not believe these work areas should be deregulated. Furthermore, they should only be deregulated if the fixed point monitoring data supports deregulation, i.e., the average concentration within the regulated area be below 1 ppm and the frequency of hourly averages exceeding one ppm be less than 15^. Some formal criteria needs to be established for meeting the 5 ppm ceiling before this area is deregulated. Lets discuss so that the proper data can be prepared. P. L. Fetzer br cc: GIF JVM CCR 000000233