Commonwealth of Pennsylvania

Environmental Protection

April 9, 1998

Subject: Source Test Review

Letterkenny Army Depot

Greene Township, Franklin County

To: Rick Millard

Air Pollution Control Engineer

Southcentral Regional Office

From: Ro bert Small

Air Pollution Control Engineer

Division of Source Testing and Monitoring

Bureau of Air Quality

Through: L. Blaine DeHaven

Chief

Division of Source Testing and Monitoring

Bureau of Air Quality

Timothy R. Brooks

Chief

Source Testing Section

Division of Source Testing and Monitoring

Bureau of Air Quality

Letterkenny Army Depot operates chromium electroplating line # 2 consisting of three hard

chrome plating tanks (tanks 6

- 8 ) at the above location.

F errous metal parts are dipped into the tanks until properly electroplated, rinsed off and dried.

The emissions from each tank are pulled by a 24 ,000 cfm I.D. fan through the ventilation system

and exhausted to a VANAIRE, Ltd. composite mesh pad chrome mist eliminator (fume

scrubber). The emissions from the scrubber are then discharged to the atmosphere through a 36

-

inch inside diameter stack.

On Oct ober 22

- 23, 1997, personnel from Vanaire conducted chromium (Cr) emission testing in

the exhaust stack serving tank nos. 6

- 8 utilizing EPA Method 306A and analyzed the samples

using graphite furnace atomic absorption (GFAAS). The purpose of the test was to demonstrate

compliance with a NESHAP MACT standard of 0.015 mg/dscm as listed in 40 CFR, Subpart N,

Section 63.342 (c) (1) (i) and establish the pressure drop across the system. Except for the

following d eviation , testing was conducted in accordance w ith acceptable sampling practices and

the conditions of the approved test protocol:Data File

Letterkenny Army Depot

Greene Township, Franklin County 2 April 9, 1998

Only one set of pressure drops across the control system were recorded in the test report. The

consultant stated that the technician monitored pressure drops across control system during all

three test runs observing no significant change in readings.

The emission concentrations were calculated correctly and appear to be valid. However, as with

August 6 test program performed by Vanaire on company ’ s electroplating l ine # 1 ( tanks 1

- 5 ) , the

test results are cons idered marginally acceptable to the Department because pressure drops across

control system were not recorded during all three test runs (see review memorandum dated April

2, 1998).

The following data was extracted from the test report:

Chromium Emission Summary for Chrome Plating Line #2

Test Date 10/22/97 10/22/97 10/22/97

Test Run Number 1 2 3

Pressure Drop during testing

(in H 2 O) Stage 1

- 0.10, Stage 2

- 0.60 & Stage 3

- 2.0

2.70 Total

Cr Emission Concentration, (mg/dscm) 0.0026 0.0039 0.0032

A llowable Cr Emission Concentration, (mg/dscm) 0.015

Tanks Contents During Testing

Tank Cell Current

(ampere) Contents Surface Area

(ft 2 )

6 1

2

3

4

5 800

850

800

800

850 1 ea. Piston Rod

1 ea. Recuperator Cylinders

1 ea. Piston Rod

1 ea. Piston Rod

1 ea. Recuperator Cylinder 2.69

3.64

2.69

2.69

3.64

7 1

2

3

4 800

850

800

850 1 ea. Piston Rod

1 ea. Recuperator Cylinder

1 ea. Piston Rod

1 ea. Recuperator Cylinder 2.69

3.64

2.69

3.64

5 800 1 ea. Piston Rod 2.69

8 1 1500 1 ea. M45 Rail 2.02

32.72Data File

Letterkenny Army Depot

Greene Township, Franklin County 3 April 9, 1998

cc: Plan Approval No. 28

- 318

- 012D

Reading File

- Source Testing Section

Data File

- Stack Testing

Compliance & Enforcement

- Scott Kepner

Division of Permits

EPA/TRB