This is a page in progress as of 3/24/2011. Please note these calculations do not yet use the correction factors determined to be appropriate on the Cheating page. The use of correction factors will increase the results shown on this page. This means the results are underestimates and are conservative.
A. Hard Chrome Plating Scrubber:
Normal Conditions Case: 0.527 mg/m3
Wildly Optimistic Case: 0.0751 mg/m3
The normal conditions case exceeds the OSHA Permissible Exposure Level in 1988 by a factor of 5.2
The wildly optimistic case exceeds the OSHA Action Level and the Local Shipyard Control Level by a factor of 1.5.
B. Decorative Plating / Aluminum Anodizing Scrubber:
Normal Conditions Case: 1.97 mg/m3
Wildly Optimistic Case: 0.28 mg/m3
The normal conditions case exceeds the OSHA Permissible Exposure Level in 1988 by a factor of 19.7.
The wildly optimistic case exceeds the OSHA Permissible Exposure Level by a factor of 2.8.
A. Calculate Amount of Electricity Used in Chrome Plating Tanks (Note 3):
1. In order to find out how much chromic acid was discharged from both scrubbers it is necessary to determine how much electrical current (Amperes) was passed through each plating tank each year. A partial year's 1988 data is provided by the Mare Island Naval Shipyard Toxic Inventory Preview of 1989. This data is as follows:
Plating Tank T-3 - Hard Chrome:: 1,300,000 Amp-hr
Plating Tank T-4 - Hard Chrome: 1,250,000 Amp-hr
Plating Tank T-5 - Hard Chrome: 2,600,000 Amp-hr
Plating Tank T-6 - Decorative Chrome: 780,000 Amp-hr
Ampere data is not available for the Aluminum Anodizing Tank. See the Cheating page for a discussion of this.
2. Adjust the Ampere-Hr Data for a Full Year:
The Toxic Inventory Preview data for these tanks is only for a partial year. In 1988 the plating shop chrome plating and anodizing operations were disrupted by the Chromic Acid spill in the air on February 17 and recovery actions, the scrubber tests is April and August, and finally the shut down of the plating shop in mid August. It is accurate to estimate the shop operated for 6.5 months during 1988. Adjusting the above Amperages to find a normal full year of operation provides:
Plating Tank T-3 - Hard Chrome:: 1,300,000 Amperes X 12 m/y / 6.5 m/1988 = 2,400,000 Amp-hr per year
Plating Tank T-4 - Hard Chrome: 1,250,000 Amperes X 12 m/y / 6.5 m/1988 = 2,307,692 Amp-hr per year
Plating Tank T-5 - Hard Chrome: 2,600,000 Amperes X 12 m/y / 6.5 m/1988 = 4,800,000 Amp-hr per year
Plating Tank T-6 - Decorative Chrome: 780,000 Amperes X 12 m/y / 6.5 m/1988 =1,440,000 Amp-hr per year
3. Consider Two Tank Operating Hours Per Day Cases:
The question that must be answered is how many hours per day was this electricity passed through the chrome plating and anodizing tanks? The fewer the hours per day the higher the amount of chromic acid is discharged through the plating shop scrubber discharges. Records are not available to show exactly how many hours per day the plating shop chrome plating and anodizing tanks were actually used and so an estimate must be used in the following calculations. These calculations consider two possible hour per day cases. One is wildly optimistic and is very unrealistic and the other is very close to how the tanks had to be actually operated. These are:
1. Wildly optimistic: Chrome plating and anodizing operations were conducted continually for 14 hours per day
2. Normal: Chrome plating and anodizing operations were conducted for two hours per day.
A review of all the complex cleaning and preparatory steps and processes necessary to prepare a metal piece to be chrome plated to military standards; considering that these steps had to be conducted within the small and crowded plating shop itself, and had to use various equipment and tanks in the plating shop allow for a good estimate that chrome plating could only have been conducted for about two hours per day at a maximum.
If you want to review all of the preparatory steps needed to prepare a piece of metal to be chrome plated you can review the Mare Island Shipyard Plating Shop Process Instruction by using these two links:
These procedures demonstrate that military specification chrome plating is not a simple or fast process. They also demonstrate that the plating shop was crowded with tanks and equipment to be used to perform many other kinds of metal treatments and plating processes, all of which had their own complex set of preparatory steps and processes. Taking everything into account a two hour per day estimate for chrome plating using the plating and anodizing tanks is about right.
B. Calculate Chromic Acid Emitted from the Hard Chrome Plating Scrubber
Data Used from April 5, 1988 and August 10, 1988 RSA hard chrome scrubber performance tests:
1. 0.00263 lb/hr Chromic acid emitted from a 95.7% efficient scrubber
2. 8275 Amperes applied to tanks to obtain 0.00263 lb/hr chrome discharge rate.
3. 17.000 Cubic Foot Per Minute (CFM) scrubber fan volume air flow
4. Normal scrubber is 17% Efficient at capturing chromic acid.
5. Normal federal work year in 1988 was 240 days.
6. Plating operations were continuous for 14 hours per day (wildly optimistic case)
7. Plating operations were continuous for 2 hours per day (normal case)
1. Calculate The Wildly Optimistic Case:
The data used in the hard chrome scrubber calculations is from the April 5, 1988 BAAQMD Supervised scrubber test. The reason for this is that this test is the one with the least cheating and the needed correction factor from the Cheating Page is small compared to the others.
The first calculation is a wildly optimistic case analysis that unrealistically assumes hard chrome plating operations were constant and uniform throughout the year for a full 14 hours per day and a 240 day federal work year. This smoothes out and fully averages the chromic acid discharged from the hard chrome plating scrubber:
A. Total hard chrome Ampere-hours: (2,400,000 + 2,307,692 + 4,800,000) Amperes = 9,507,000 Amp-hr per year total
B. 95.7% Efficient scrubber total chromic acid emitted per amp-hr: 0.00263 lb/hr / 8275 Amperes = 3.178 x 10-7 lb/amp-hr
C. Adjust to 17% Efficient scrubber: 3.178 x 10-7 lb/amp-hr X 95.7% / 17% = 1.789 x 10,-6 lb/amp-hr
C. Total yearly chromic acid emitted: 1.789 X 10-6 lb/amp-hr X 9,507,000 Amp-hr = 17.01 lb/year
D. Convert lb to mg: 17.01 lb/yr X 454 gram/lb X 1000 mg/gram = 7,722,361 mg/yr
E. Calculate yearly scrubber air flow:
(17,000 CFM X 60 min/hr X 14 hours/day X 240 days year) / 33.31 m3/ft3 = 102,888,021 m3 /yr
F. Calculate chromic acid discharged in mg/m3: 7,722,361 mg/yr / 102,888,021 m3/yr = 0.0751 mg/m3 wildly optimistic case.
This exceeds 50% of the OSHA PEL of 0.1 mg/m3 and trips the local shipyard control and OSHA Action Level requirements.
2. Calculate Normal Case:
The problem is the plating shop did not hard chrome plate continuously for 14 hours per day for 240 days per year. Plating operations were not continuous because the shop could not possibly sustain such a workload to prepare so much metal to be plated, and the operation of the plating tanks was dependent upon how quickly items to be plated could be sent from other shops to the plating shop and then prepared for plating inside the plating shop.. Plating was also held up due to plating shop maintenance and ventilation equipment break downs. It is safe, for a normal case analysis, taking all these factors into account, to estimate a real time two hours per day of hard chrome plating took place in a normal year. With this the normal case analyses is calculated as follows:
A. Adjust 14 hr/day best case to 2 hr/day normal case: 0.0751 mg/m3 X 14 hr/day / 2 hr day = 0.5257 mg/m3
This exceeds the OSHA PEL of 0.1 mg/m3 by a factor of 5.2.
C. Calculate Chromic Acid Emitted from the Decorative Chrome/Anodizing Scrubber
Data Used BAAQMD, April 6, 1988 and August 17, 1988 RSA hard chrome scrubber performance tests:
1. 0.00213 lb/hr Chromic acid emitted from a 93% efficient scrubber (Note 1)
2. 1000 Amperes applied to tanks to obtain 0.00213 lb/hr chrome discharge rate. (Note 2)
3. 10,557 Cubic Foot Per Minute (CFM) scrubber fan volume air flow
4. Normal scrubber is 7% Efficient at capturing chromic acid.
5. Normal federal work year in 1988 was 240 days.
6. Plating operations were continuous for 14 hours per day (wildly optimistic case)
7. Plating operations were continuous for 2 hours per day (normal case)
1. Calculate Wildly Optimistic Case:
The first calculation is a wildly optimistic case analysis that assumes decorative chrome plating operations were constant and uniform throughout the year for a full 14 hours per day and a 240 day federal work year. This smoothes out and fully averages the chromic acid discharged from the decorative chrome plating scrubber:
A. Total hard chrome Ampere-hours: 1,440,000 Amp-hr per year total
B. 93% Efficient scrubber total chromic acid emitted per amp-hr: 0.00213 lb/hr / 1000 Amperes = 2.13 x 10-6 lb/amp-hr
C. Adjust to 7% Efficient scrubber: 2.13 x 10-6 lb/amp-hr X 93% / 7% = 2.83 x 10-5 lb/amp-hr
C. Total yearly chromic acid emitted: 2.83 X 10-5 lb/amp-hr X 1,400,000 Amp-hr = 39.62 lb/year
D. Convert lb to mg: 39.62 lb/yr X 454 g/lb X 1000 mg/g = 17,986,572 mg/yr
E. Calculate yearly scrubber air flow:
(10,557 CFM X 60 min/hr X 14 hours/day X 240 days year) / 33.31 m3/ft3 = 63,893,461 m3 /yr
F. Calculate chromic acid discharged in mg/m3: 17,986,572 mg/yr / 63,893,461 m3yr = 0.28 mg/m3 wildly optimistic case.
This exceeds the OSHA PEL of 0.1 mg/m3 by a factor of 2.8.
2. Calculate Normal Case:
The problem is the plating shop did not hard chrome plate continuously for 14 hours per day for 240 days per year. Plating operations were not continuous because the shop could not possibly sustain such a workload to prepare so much metal to be plated, and the operation of the plating tanks was depended upon how quickly items to be plated could be sent from other shops to the plating shop. Plating was also held up due to plating shop maintenance and ventilation equipment break downs. It is safe, for a worst case analysis, taking all these factors into account, to estimate a real time two hours per day of decorative chrome plating took place in a normal year. With this the normal case analyses is calculated as follows:
A. Total hard chrome Ampere-hours: 1,440,000 Amp-hr per year total
B. 93% Efficient scrubber total chromic acid emitted per amp-hr: 0.00213 lb/hr / 1000 Amperes = 2.13 x 10-6 lb/amp-hr
C. Adjust to 7% Efficient scrubber: 2.13 x 10-6 lb/amp-hr X 93% / 7% = 2.83 x 10-5 lb/amp-hr
C. Total yearly chromic acid emitted: 2.83 X 10-5 lb/amp-hr X 1,400,000 Amp-hr = 39.62 lb/year
D. Convert lb to mg: 39.62 lb/yr X 454 g/lb X 1000 mg/g = 17,986,572 mg/yr
E. Calculate yearly scrubber air flow:
(10,554 CFM X 60 min/hr X 2 hours/day X 240 days year) / 33.31 m3/ft3 = 9,125,043 m3 /yr
F. Calculate chromic acid discharged in mg/m3: 17,986,572 mg/yr / 9,125,043 m3/yr = 1.97 mg/m3 normal operations case
This exceeds the OSHA PEL of 0.1 mg/m3 by a factor of 19.7
These results do not contain a contribution from the anodizing tank. The April 6, 1988 BAAQMD and August 17, 1988 RSA tests dishonestly minimized the electrical current to the anodizing tank so that it would produce effectively zero emissions. Calculations to follow will estimate the missing anodizing tank contribution to the chromic acid emitted from this scrubber.
D. Calculate Total Pounds of Chrome VI Discharged from the Plating Shop Per Year:
1. Normal case Hard Chrome Plating:
17.01 lb/year multiplied by the adjustment to covert wildly optimistic estimate to normal estimate
0.5257 mg/m3/0.0751 mg/m3 = 119.07 lb/year
2. Normal case for Decorative Chrome Plating:
39.62 lb/year
The total is 119.07 + 39.62 = 158.69 lb/year.
Notes:
1. This value was cited and used by U.S. Navy in Management Exhibit No. 11. See the Perjury page.
2. This value is from the April 6, 1988 BAAQMD supervised test. It is more likely that during this test an honest normal decorative chrome plating amperage was used.
3. This page of calculations uses the actual Ampere-hour data whereas the U.S. Navy Perjured calculations do not. This Ampere-hour data is used in the calculations on this page because it provides a more accurate assessment of the amount of time per year that the plating tanks were actually used. Knowing exactly how much the tanks were used allows a more accurate calculation of the amount of chromic acid discharged into the air and this is probably why this data was not used by the Navy in its dishonest perjured document.