Document ID: EPA-HQ-OAR-2002-0034-0231
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2007-04-17T04:00Z

Since our initial ‘Request for Clarification’ document, dated
October 9, 2003, the following additional issues have been identified by
AFS members as items in need of clarification.  

17.  Pages 12 and 51 - §§63.7690(b)(3), 63.7732(b)(3) and (c)(3) –
Defining Cupola “Blast” Conditions

The rule requires that the cupola afterburner be operated such that the
combustion zone temperature does not fall below a 1,300 oF average
except for “periods when the cupola is off blast and for 15 minutes
after going on blast.”  Likewise, the rules require that sampling be
conducted “only during times when the cupola is on blast.”  The
industry is concerned that the term “blast” is not defined within
the rule or discussed in the preamble and could be misinterpreted to
mean any period when “blast” air is entering the cupola.  This is
problematic because blast air is often used during non-production
(i.e.,non-representative) periods such as preparing the cupola for
operation.

When a cupola furnace is initially started the equipment must be
properly prepared before melting can commence.  Typically, the procedure
commences with building a sand bed in the bottom of the furnace.  The
sand bed is used to direct the molten metal to the point where it will
be drawn from the furnace.  Next, a bed of coke is added and ignited,
commonly utilizing the blast air, and allowed to burn for approximately
one hour.  When the coke bed is established and the cupola furnace is at
the proper temperature, the blast air is shutdown and the furnace is
charged with metals, coke, and limestone.  After the cupola furnace is
fully charged, the blast air is again introduced and the metal begins to
melt.

It is requested that the Agency confirm that the term “blast” means
those periods when blast air is being introduced to the cupola furnace
and the furnace is capable of producing molten metal.  Specifically, the
term “blast” should not include those periods when blast air is
being introduced to the cupola furnace for purposes of initially heating
the furnace, prior to charging the metals.  

An improper interpretation of the term “blast” could result in the
unnecessary requirement to maintain a 1,300 oF afterburner temperature
during the latter phase of the startup period, when the emissions lack
an adequate concentration of carbon monoxide (CO) to sustain combustion.
 Likewise, an improper interpretation of this term could allow sources
to include within their performance test results those startup periods
where emissions are unnaturally minimal.

18.  Page 11 - §§63.7690(b), 63.7710(b)(2), 63.7733, 63.7743(b),
(d)-(f), and 63.7765 – Definition of “Deviation”

The rule requires that operating limits be established during
performance testing for each capture system and for each of the various
control devices (e.g., pressure drop and water flow for a wet scrubber,
flow rate for an acid scrubber, and temperature for a combustion
device).  Foundries are then required to operate these capture systems
and control devices at levels that meet these operating limits at all
times.  The rule defines a “deviation” to include “any instance”
in which a source “fails to meet any requirement or obligation”
including operating limits.  The industry is concerned that the rule
could be interpreted such that any deviation from an operating limit is
required to be identified as a “violation.”  We do not believe that
this is an appropriate application of the operating limits and request
that the Agency clarify their use.

Specifically, the industry requests that the Agency adopt the approach
taken in the recently signed NESHAP for Industrial Boilers and Process
Heaters.  In this rulemaking the definition of ‘deviation’ includes
the statement:

A deviation is not always a violation.  The determination of whether a
deviation constitutes a violation of the standard is up to the
discretion of the entity responsible for enforcement of the standards.

Alternately, the Agency is encouraged to adopt into the Foundry NESHAP
the position that exceedances of the operating limits are to trigger
corrective actions and that, only if the corrective actions are not
taken promptly, or if the corrective actions are not successful in
returning the operating parameter to within the specified range, has a
deviation occurred.  This approach is consistent with the NESHAP for
Coke Ovens [68 FR 18009, April 14, 2003].  

If the corrective action is not successful, the owner or operator must
take additional corrective actions.  If the second attempt to fix the
problem is not successful, the failure must be reported as a deviation.
[68 FR at 18009].

This approach is also consistent with the previously published Agency
statement:  

… a change in a control device’s operating parameter does not
directly correlate with an increase in emissions and does not provide a
reasonable assurance that the emission limitation was exceeded when the
parameter changed.  …  In other words, the operating parameter may be
outside the limit established during the performance test while
emissions are still below the applicable limit.  The primary value of
monitoring the control device parameters is to detect a potential
problem with the device’s operation as soon as possible and to
promptly investigate and correct the cause.  [Primary Aluminum NESHAP,
Proposed Rule, 61 FR 50590].

Because several NESHAPs have adopted varying interpretations of the
requirement to maintain operating limitations, and because the Iron and
Steel Foundry NESHAP is silent on this issue, the industry requests that
the Agency provide clarification.

19.  Page 134 – §63.7731(b) and §63.7750(d) – Notification of
Subsequent Opacity Tests

The rule, at §63.7731(b), requires a performance test to demonstrate
compliance with the opacity limit be conducted no less frequently than
once every 6 months.  In addition, §63.7750(d), requires that a
“notification of intent to conduct a performance test” must be
submitted at least 60 days prior to performing the test.  The industry
group requests that the Agency reconsider the applicability of the
notification requirement to opacity testing events.

Specifically, due to the ease of preparation prior to conducting an
opacity test, the brief period of the test, the effect of weather
conditions on performing such a test, and the ability to readily repeat
an opacity test, the industry group does not believe that a notification
is necessary.  In those instances when an enforcement official seeks to
monitor an opacity performance test, the test can readily be repeated in
their presence.  In fact, any agency inspection of a foundry will likely
include an informal, and if deemed appropriate a formal, opacity review.
 As such, the notification requirement presents a reporting burden with
no benefit and a great potential for administrative noncompliance.

NESHAP for Iron and Steel Foundries

Request for Clarification

Prepared by American Foundry Society

Submitted to EPA on April 1, 2004