ML20216H730

Proposed Tech Specs,Adding Definition of Calculated Bulk Core Temp & Core Average Inlet Temp for Determination of Core Temp

ML20216H730
Person / Time
Site:	Fort Saint Vrain
Issue date:	06/25/1987
From:	PUBLIC SERVICE CO. OF COLORADO
To:
Shared Package
ML20216H727	List: ML20216H722 ML20216H730 ML20216J473
References
TAC-52634, NUDOCS 8707010544
Download: ML20216H730 (27)

Text

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s ATTACHMENT 2 i

PROPOSED CHANGES I

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Fort St. Vrain 01 a

Technical Specifications Amendment No.

Page 2-9 2.23 CALCULATED BULK CORE TEMPERATURE The CALCULATED BULK CORE TEMPERATURE shall be the calculated average temperature of the core, including graphite and

fuel, but not the reflector, assuming a loss of all forced circulation of primary coolant flow.

2.24 CORE AVERAGE INLET TEMPERATURE The CORE AVERAGE INLET TEMPERATURE shall be the arithmetic average of the operating circulator inlet temperatures, j

adjusted for circulator power input, steam g.'nerator 3

regenerative heat loads, and PCRV liner cooling system heat losses.

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a

.c-Fort St. Vrain 01 Technical Specifications Amendment No.

Page 4.0-1 1

4.0 LIMITING CONDITIONS FOR OPERATION 4.0.1 The Limiting Conditions for Operation, specified in this section, define the lowest functional

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capability or performance levels necessary to assure safe operation of the facility.

These Limiting Conditions for Operation provide for operation with sufficient redundancy so that further, but limited, degradation of equipment capability or performance, or the occurrence of a postulated incident will not prevent a safe reactor shutdown.

4.0.2 These Limiting Conditions for Operation do not replace plant operating procedures.

Plant operating procedures establish plant operating l

conditions with -at least the capability and performance specified in these Limiting Conditions for Operation.

i 4.0.3 Violation of a Limiting Condition for Operation l

I shall be corrected as soon as practicable.

Unless j

1 otherwise stated in these specifications, the i

1 condition would be corrected or the reactor shall

}

be shutdown in an orderly manner within a 24-hour period.

Fort St. Vrain #1 Technical Specifications Amendment No.

Page 4.0-2 4.0.4 Where the Applicability of a FSV Technical Specification is defined in terms of the CALCULATED BULK CORE TEMPERATURE, the time at which this temperature reaches 760 degrees F following an interruption of all primary coolant flow is the time after which specification requirements are applicable.

The time for the CALCULATED BULK CORE TEMPERATURE to reach 760 degrees F following an interruption of all primary coolant flow is determined as follows:

a.

Using the applicable operating power history prior to interruption of primary coolant flow, determine the decay heat power from Figure 4.0-1.

b.

Using this decay heat power and the average core temperature prior to the primary coolant flow interruption, determine the time tequired to reach 760 degrees F from Figure 4.0-2.

c.

The maximum time for which primary coolant flow can be interrupted is the time interval determined in Specification 4.0.4.b, not to exceed 21 days.

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4 Fort St. Vrain #1 Technical Specifications Amendment No.

Page 4.0-5 BASIS for SPECIFICATION 4.0.4 s

The CALCULATED BULK CORE TEMPERATURE is the calculated, time dependent, average temperature of the' core, including 4

I graphite and fuel, but not the reflector, assuming a loss i

of all forced circulation of primary coolant flow.

The calculation uses several conservative assumptions:

1) The decay heat power at the start of the core heatup has been conservatively selected using Figure 4.0-1 and is assumed to remain constant for the total interval; 2) All decay heat power generated is assumed to be retained in the active core with no heat transfer to the reflector, PCRV internals or primary coolant; and 3) A 10 percent margin has been included on the core heatup time given in Figure 4.0-2.

If the active core remains below 760 degrees F, which corresponds to the design maximum core inlet temperature, then there can be no damage to fuel or i

PCRV internal components, even in the absence of forced circulation of primary coolant helium flow.

-~

s Fort St. Vrmin #1 Technical Specifications Amendment No.

Page 4.0-6 The time required to reach a CALCULATED BULK CORE TEMPERATURE of 760 degrees F is primarily dependent upon the decay heat power and the current average core temperature. This time is conservatively estimated using the data in Figures 4.0-1 and 4.0-2.

The decay j

heat power data in Figure 4.0-1 was explicitly calculated for the Fort St. Vrain core and is derived from Appendix D.1 of the FSAR, Figure D.1-9, revision 2.

The decay heat power resulting from a varying power history can be conservatively calculated by representing the actual power hi story by a series of constant power steps and then summing the individual decay heat power contribution from each power step.

The decay heat power due to operation during the last 1000 days can be determined in this manner.

Residual decay heat power from earlier operation is conservatively estimated by assuming that this was full power continuous operation, and by then adding this decay heat power component to the calculated decay heat power value.

Fort St. Vrain #1 Technical Specifications Amendment No.

Page 4.0-7 Knowing the decay heat power and the current average core temperature, the time for the core to heat up from its

)

current temperature to 760 degrees F can be obtained from Figure 4.0-2, which has been generated using the adiabatic heat transfer model and a heat capacity for composite graphite as given in Appendix D.1 of the FSAR, Figure D.1-3, revision 2.

To allow for uncertainties associated with determining the time to reach a CALCULATED BULK CORE TEMPERATURE of 760 degrees F,

an additional 10 percent has been included in j

1 the decay heat energy given in Figure 4.0-2.

In addition, it has been specified that any time interval for which the

{

l primary coolant flow is interrupted shall not exceed 21 days. This ensures a restoration of forced circulation of primary coolant flow to confirm core average temperature on a periodic basis. Although much longer intervals can be determined from Figure 4.0-2, 21 days is an adequate time to conduct operations requiring flow interruption, such as maintenance or circulator changeout.

Operating experience at Fort St. Vrain has shown that the calculated core heatup rate has always been higher than the actual core heatup rate.

J Fort St. Vrain 01 a

Technical Specifications Revision 13 - 6/29/76 Page 4.1-14 l

Basis for Specification LC0 4.1.8 An unexpected and/or unexplained change in the observed core reactivity could be indicative of the existence of potential safety problems or of operational problems.

A reactivity anomally greater than 0.01 delta k would be unexpected, and its occurrence would be throughly investigated and evaluated.

The value of 0.01 delta k is considered to be a safe limit since a shutdown margin of at least 0.01 delta k with the highest worth rod pair fully withdrawn is always maintained (see LCO 4.1.2).

i i

i Fort St. Vrain #1 Technical Specifications Amendment #

Page 4.1-15

'LCO 4.1.9 CORE INLET ORIFICE VALVES / MINIMUM HELIUM FLOW and MAXIMUM CORE REGION TEMPERATURE RISE s

3 LIMITING CONDITION FOR'0PERATION The total helium circulator flow or the helium coolant temperature rise for all core regions shall~be maintained within the limits given in Table 4.1.9-1.

APPLICABILITY: Whenever the reactor is. operated at POWER *, in LOW POWER OPERATION, or with the REACTOR SHUTDOWN **.#

l ACTION:

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+

a.

In POWER or LOW POWER, with any of the above limits exceeded, either:

1.

Correct. the out-of-limit condition within 15 minutes, or 2.

Be in at least REACTOR SHUTDOWN within I hour with the j

inlet orifice valves adjusted'for equal region. coolant flows within the following 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and, if the

, j applicable limits are still

exceeded, initiate PCRV

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depressurization within the following 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />.

l b.

In REACTOR SHUTDOWN with the. inlet orifice valves adjusted for equal region. flows, with 'any of the above limits exceeded, either:

a1 1.

Correct the out-of-limit condition within 15 minutes,

j or 2.

Initiate -PCRV depressurization within the time limits of Figure 4.2.18-1 of LCO 4.2.18.

Up to the power levels for which limits are shown in Figures q

4.1.9-1,

-3, and -5.

t l

With the CALCULATED BULK CORE TEMPERATURE greater;than 760 degrees F as provided in Specification 4.0.4.

1 POWER includes operation greater than 2'4 RATED THERMAL POWER j

per Definition 2.10, LOW POWER OPERATION is per Definition 215,

'i REACTOR SHUTDOWN is per Definition 2.14.

., n.

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a j

Fort St. Vrain #1 l

o Technical Specifications Amendment #

Page 4.1-16 c.

In REACTOR SHUTOOWN with the inlet orifice valves adjusted at any other position, with any of the above limits exceeded, either:

i 1.

Adjust the inlet orifice valves to equal region coolant i

flows and be within the above limits within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, or 2.

Initiate PCRV depressurization within the time limits of Figure 4.2.18-1 of LC0 4.2.18.

ASSOCIATED SURVEILLANCE REQUIREMENT:

SR 5.1.8 l

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Fort St. Vrain 01-Tochnical Specifications Amendment #

Page 4.1-17 1

Table 4.1.9-1 l

4n Region Orifice l Reactor Pressure l Limiting Condition Position l Helium Density l

for Operation i

I All. regions set l Greater than 50 l The total helium circulator for equal region l psia, with l flow shall be greater than coolant flow *** l helium density

• l or equal to the minimum EXCEPT l greater than I allowable value shown in Up to 10 regions l 60%, but less l Figures 4.1.9-1 or 4.1.9-2.

may have their l than, or equal l

orifices further i to,107.5%.

l open.

l l

l l_

As above.

l Greater than 50 l The total helium circulator i psia with helium l flow shall be greater l density

• 1ess l than, or equal to, the l than, or equal l minimum allowable value shown l to, 60%.

[ in Figures 4.1.9-3 or 4.1.9-4 I

I l

All regions set l Less than or l The helium coolant tempera,ture for equal region l equal to 50 psia.l rise ** through any core region coolant flow.***l l shall not exceed 600 degrees l

l F.

I I

Orifice valves l Greater than l The helium coolant temperature at any position l 50 psia.

l rise ** through any core region (Adjusted for l

l shall not exceed the limit nominal equal l

l shown in Figure 4.1.9-5.

region outlet l

l temperature).

l l

l l

J Orifice valves l Less than or l The helium coolant temperature.

at any position l equal to 50 psia.1 rise ** through any core region (Adjusted for l

l shall not exceed 350 degrees nominal equal l

l F.

region outlet l

l temperature).

l l

l t

Percent helium density equals:

175.12 x Reactor pressure (psia)

~

(Circulator 1nlet temperature (degrees F) plus 460)

Helium coolant temperature rise equals INDIVIDUAL REFUELING REGION OUTLET TEMPERATURE minus CORE AVERAGE INLET TEMPERATURE.

1

• • • Equal region coolant flow with 7 column region orifice valves set between 8% and 20% open (or the corresponding position for 5 column regions).

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d Fort St. Vrain #1 Technical Specifications Amendment #

Page 4.1-19 ORIFICE VALVES ADJUSTED FOR EQUAL REGION COOLANT FLOW

> 60% TO i 107.5% HEI.,10M DENSITY 50 PSI A REACTOR PRESSURE I

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i l

Page 4.1-21 ORIFICE V ALVES ADJUSTED FOR EQUAL REGION COOLANT FLOW s 60% HELIUM DENSITY

> 50 PSI A REACTOR PRESSURE l

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.x 1.,

Fort St. Vrain n Technical Specifications Amendment #

Page 4.1-23

(

l BASIS FOR SPECIFICATION LC0 4.1.9 The' minimum helium circulator flow or.the maximum core region a

helium coolant temperature rise as a function of-calculated i

reactor THERMAL POWER (including power from decay heat) have

)

been specified to prevent very low helium coolant flow rates

{

through any coolant channel.

.Very low helium coolant flow j

rates may result in laminar flow conditions with resultant high friction factors and' low heat transfer film coefficients and potential for possible local helium flow stagnation or - reverse flow, which could result in excessive fuel temperatures.

This specification addresses minimum flow requirements for all coolant channels.

Since low coolant flows exist at lower reactor powers, its applicability is limited, to less than approximately 25% RATED THERMAL POWER.

Specific power level end points for given conditions are as shown on the Figures.

Since THERMAL POWER is continuously-' generated' by decay heat even after the reactor is ' shutdown, the. flow requirements are also applicable in the REACTOR SHUTDOWN mode.

This specification is not applicable during SHUTDOWN when the CALCULATED BULK CORE TEMPERATURE is. less than 760 degrees F.

Specification 4.0.4 provides the methodology and necessary data to determine the appropriate time interval to reach a

CALCULATED BULK CORE TEMPERATURE of 760 degrees F.

If the active core remains below this temperature,

. hich corresponds w

to the design maximum core inlet temperature, then the design core inlet temperature can not be exceeded and there can be no damage to fuel or PCRV internal components regardless of the

amount, including total absence, or reversal, of primary

{

coolant helium flow.

o The applicability of this Specification is also limited to the range of power level indicated in Figures 4.1.9-1, 4.1.9-3, and I

4.1.9-5.

Above the power levels for which limits are shown in these Figures, the Reactor Core Safety Limit, Specification 3.1, governs.

In addition to this Specification, fuel integrity is ensured for power levels from 0 to 100% by limiting the INDIVIDUAL REFUELING REGION OUTLET TEMPERATURES to values given in Specification 4.1.7.

The core flow fraction limits shown in Figures 4.1.9-1, 4.1.9-2, 4.1.9-3, and 4.1.9-4 are based on, and thus valid for, equal. region coolant flow orifice settings within the range of 8% to 20% open for seven column regions and the corresponding settings for five column

regions, i.e.; within the range of 4.4% to 13.4% open for five

'1 column regions.

Equal region outlet temperature orificing is precluded below about 3% power by Figure 4.1.9-5 because

)

uncertainties in instrumentation exceed the allowable temperature rise.

)

Fort St. Vrain 01 Technical Specifications I

Amendment #

)

Paga 4.1-24 The limits have been developed based upon a number of conservative assumptions.

For the limits in Figures 4.1.9-1, 4.1.9-2 and 4.1.9-5, it was assumed that the primary system was pressurized to 107.5 percent of design helium density.

At lower densities higher region temperature rises and lower primary coolant flow are acceptable.

Since startup operations can proceed with lower helium densities, after the reactor nas been pressurized to greater than 100 psia, which corresponds to about 30 percent helium inventory at 200 degrees F, flow requirements were calculated for 60% helium density and are given in Figures 4.1.9-3 and 4.1.9-4.

Percent helium density i

equals:

175.12 x Reactor Pressure (psia)

(Circulator inlet temperature (degrees F) plus 460)

The core inlet helium temperature used in the analysis covers the range of 100-400 degrees F between 0 and 5% RATED THERMAL POWER and 100-700 degrees F above 5% RATED THERMAL POWER.

These are reasonable assumptions for low power operation.

1 The analysis is based on operation of two circulators between 0 i

and 5% RATED THERMAL POWER and four circulators above 5% RATED THERMAL POWER.

This is consistent with plant operation.

In the analysis to determine the limits, the effects of heat conduction between columns in a region, or between regions, were conservatively neglected.

Envelope values of RPF/ Intra Region Peaking (3.0/1.25 and 1.6/1.61) were used to anticipate worst case conditions considering all future fuel cycles.

Consistently conservative nominal values and uncertainties were used for bypass flows and measured parameters throughout the analysis.

For the condition with orifice valves at any position, the allowable region delta T is based upon a region peaking factor equal to 0.4.

For regions with higher power densities, higher region delta T's are acceptable.

The circulator flow determination is normally based on the empirical relationship between flow and circulator inlet nozzle delta P,

local temperature, and local pressure. The uncertainties associated with control room indication of these parameters were accounted for in the analysis.

Other flow determination methods are acceptable provided the associated uncertainties are accounted for and the calculated circulator flow is adjusted accordingly.

1 Fort St. Vrain #1 i

.4 Technical Specificationr Amendment #

Page 4.1-25.

Besides the minimum flow requirement ' curves with the orifices set for equal region flows in Figures 4.1.9-1, 4.1.9-2, 4.1.9-3, and 4.1.9-4, flow requirements are provided with up to 10.

orifice valves positioned further~ open.

These curves-. assist in the transition between equal region flows and equal region outlet gas temperatures. By monitoring the total circulator flow ~when-the orifices are adjusted for equal region coolant flows, minimum flow through each region at the appropriate

)

power can be ensured. When the orifice valves are adjusted to

-different positions, minimum coolant flows can be ensured for each. region. by-monitoring the helium coolant temperature rise in that region. Maximum temperature-rise requirement curves are presented for the case where the inlet orifice valves are adjusted to any position as well as the cases where no seven column orifice valve is closed to less than 8% or less than 6%

open (or the corresponding position for five column regions).

For. depressurized' operations, helium coolant temperature rise i

limits are also specified to prevent very low helium coolant i

flow rates through any coolant channel. -These limits have been established based upon a 50 psia reactor pressure.

To ensure that flow stagnation in a fuel column or region does not persist, an ACTION time of only 15 minutes is allowed to correct the out of limit' condition.

The requirement to be in REACTOR' SHUTDOWN within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> with the orifices set for equal flows' in an additional' 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is realistic because it takes approximately 4 - 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to set the orifice valves from equal temperatures to equal region flows.

This is considered acceptable since there is sufficient primary coolant flow from the circulators which are driven by steam generated from residual heat in the system following REACTOR SHUTDOWN.

If, after this action,.there is still inadequate flow, depressurizing the PCRV further reduces the tendency toward stagnation and reverse flow.

i l

1 s

Fort St. Vrain #1 a

Technical Specifications Amendment #

Page 5.1-16

)

4 SPECIFICATION SR 5.1.8 - MINIMUM HELIUM FLOW / MAXIMUM CORE REGION TEMPERATURE RISE SURVEILLANCE REQUIREMENT j

i The total helium circulator flow or the helium coolant temperature rise through each core region shall be determined to be within the limits of LCO 4.1.9 at least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

l i

BASIS for SPECIFICATION SR 5.1.8 Surveillance of the helium circulator flow or helium coolant temperature rise once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> ensures that the requirements of LC0 4.1.9 are met.

In addition, plant procedures require that the flow rate, core outlet temperatures, and power level be monitored continuously whenever the power level is being changed or orifice j

valves are being adjusted.

In performance of the surveillance, the total reactor helium coolant flow is determined by calculation consistent with the method used to determine the required flow for the j

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ASSOCIATED LCO:

LC0 4.1.9 I

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4 ATTACHMENT 3 SAFETY ANALYSIS I

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O SAFETY ANALYSIS This Technical Specification specifies minimum allowable total flow and maximum allowable region temperature rise to assure that flow stagnation. or reversal does not occur and thus, that excessive fuel temperature is prevented.

These limits are necessary between 0%

and approximately 25% power bacause the core power-to-flow ratio limits of Safety Limit 3.1 and the region outlet. temperature mismatch limits of Specification.LC0 4.1.7 do not, by themselves, preclude the adverse flow conditions. At higher power levels, the power-to-flow and region outlet temperature limits are sufficient to preclude excessive fuel temperatures and fuel failure.

The proposed Specification corrects errors in the original analysis, includes allowances for explicit uncertainties associated with thermal power and total circulator flow-(instrument errors) measurements, and makes the assumptions consistent with operation.

In addition, minimum coolant flow curves were added for 1 to 10 orifice valves more open than the equal flow position, and maximum region temperature rise limit curves were added when no orifice valve is less than 6% and 8% open, to facilitate the' transition from equal flow positions to equal region outlet temperature positions. Minimum coolant flow curves were also added for reduced helium density conditions since the lower densities result in smaller helium buoyancy effects.

1 The proposed flow and temperature limits are significantly more restrictive than the corresponding limits in the existing Technical Specification.

The new curves that have been added to permit operation when up to 10 orifice valves are further open than the equal flow position have the same degree of conservatism that is included in the equal flow position curves.

In determining the total circulator flow requirements it was assumed that any orifice valve further open was full

open, and the total circulator flow requirements were increased so that the minimum flow in any coolant channel would not be less than that required when all orifice valves are set for equal flow.

The same philosoohy was applied when generating the new curves to limit the maximum region temperature rise when the orifice valves are set at any position but no orifice valves are less than either 6% or 8% open.

The applicability of the proposed Specification has been limited when the reactor is in the SHUTDOWN mode to that condition when the CALCULATED BULK CCRE TEMPERATURE is greater than 760 degrees F.

This excl.udes the case when the amount of. thermal energy' from fission product decay is sufficiently low to prevent the average core temperature from exceeding 760. degrees F for the calculated-time interval even if there is no forced circulation of primary coolant flow.

The detailed description and justification for this is provided in the revision to Specification 4.0.4, and in Attachment 4 to P-86169, dated February 28, 1986.

The design helium coolant temperatures at full power are 760 degrees F (core inlet and upper plenum) and 1460 degrees F (core outlet and steam generator inlet).

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The upper plenum internal components, including the control rod drive and orifice assembly and thermal barrier, have been designed to be consistent with this temperature environment.

j Consequently, limiting the CALCULATED BULK CORE TEMPERATURE during a primary coolant flow interruption to 760 degrees F

will conservatively ensure that both the core and PCRV internals will be protected when the forced circulation of primary coolant flow is resumed.

This is consistent with the conclusion reached by ORNL in their independent review (FIN No. A9351).

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In compliance with 10 CFR 50.59, the following questions are addressed:

1) Has the probability of occurrence or the consequences of an accident or malfunction 'of equipment important to safety previously evaluated in the FSAR been increased?

No.

The FSAR has been reviewed and this change has no impact on i

the probability or consequence of any of the accidents analyzed.

Since the proposed changes increase the minimum flow requirements i

and decrease the allowable region temperature rise, they preclude flow stagnation or reversal, and are therefore consistent with any accident previously analyzed in the FSAR.

2) Has the possibility of an accident or malfunction of a different type than any evaluated previously in the FSAR been created?

No.

The proposed Specification change does not involve any modification to plant systems, equipment, or structures.

The only changes to procedures are to ensure compliance with the revised limits.

Thus, these changes will not create a new or different type of accident or malfunction.

3) Has the margin of safety, as defined in the basis for any Technical Specification been reduced?

No.

A review of the margins of safety associated with this Technical Specification confirms that the margins of safety are not reduced by this change.

In fact, the new limits represent an increase in the minimum flow required and a decrease in the allowed temperature rise.

Both these changes provide additional assurance that excessive fuel temperatures are prevented.

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i ATTACHMENT 4 SIGNIFICANT HAZARDS CONSIDERATION

t SIGNIFICANT HAZARDS CONSIDERATION I.

Evaluation From the safety analysis provided in' Attachment 3 and the proposed Technical Specification change, it can be seen that the proposed revision corrects errors, includes allowances for uncertainties, and that the proposed minimum flow and maximum region temperature rise limits are all more restrictive than the existing Technical Specification.

In addition, the new curves added maintain at least the same degree of conservatism. Consequently, this proposed revision does not result in an unreviewed safety question.

1)

FSAR accident analyses have been reviewed to determine the effect, if any, of this change on these analyses.

Since the proposed changes increase the minimum flow requirements and decrease the.

allowable region temperature rise, they preclude flow stagnation or reversal,_and there is no adverse impact on any accident previously analyzed in the FSAR.

2)

The proposed Technical Specification change does not involve any modification of plant systems, equipment, or structures.

The only changes to plant operating procedures are to ensure _ compliance.with the revised limits.

Thus, these changes would not create a new or different type of accident than any previously evaluated.

3)

A review of the margins of safety associated with this Technical Specification confirms that the margins of safety are not reduced by this change. 'In fact, the new limits represent an increase in the minimum flow required and a decrease in the allowed temperature rise.

Both these changes provide additional assurance that-excessive fuel temperatures are prevented.

II. Conclusion Based on the above evaluation, it is concluded that operation of Fort'St. Vrain in accordance' with the proposed changes will

.not (1) involve a significant-increase. in the probability or consequences of _an accident previously evaluated, (2) create the possibility of a new or different kind of accident from any accident previously evaluated, or (3) involve a significant reduction in a margin of safety.

Therefore, this change will not create an undue risk to the health and safety of the public nor does it involve any significant hazards consideration.