..I' pf C!.' Iv RNIA CALIFORNIA ENVIRONMENTAL ......San Francisco, CA 94105 Mr. Jim Ross (w/o attachment) L.A. Regional Water Quality Control Board 101 Centre Plaza Drive Monterey

..I' pf C! .' Iv RNIA CALIFORNIA ENVIRONMENTAL PROTECTION AGENCY PETE WILSON. Governor

PARTMENT OF TOXIC SUBSTANCES CONTROL1011 N . GRANDVIEW AVENU E

GL LE . CA 9120 1

(f"1800 January 22, 199 6

CERTIFIED MAIL

Mr . Randy UeshiroSSFL Project LeaderRocketdyne DivisionRockwell International Corporation

6633 Canoga Avenue

Canoga Park, CA 91309-7922

Dear Mr . Ueshiro :

Return Receipt RequestedP 533 720 18 2

NOTICE OF DEFICIENCIES, ROCKWELL, SANTA 8USANA FIELD LABORATORY

RCRA FACILITY INVESTIGATION WORKPLAN ADDENDUM

The California Environmental Protection Agency, Department

of Toxic Substances Control (DTSC) has reviewed the RCRA Facility

Investigation Workplan Addendum (Workplan) dated March 1995 .

Enclosed are DTSC's comments on the Workplan . Conditions which

were added since the draft that you received on December 6 for

our conference call have been highlighted in bold type . Also,

address the comments in the enclosed memorandums on the

Workplanls Health and SafetyPlan and Risk Assessment .

As discussed during our December 6 conference call, Rockwell

may submit revised sections of the plan as they are completed .

Please revise the schedule presented in the December 15 letter to

DTSC and indicate when each of the sections will be completed by

January 31, 1995 .

If you. have any questions, please contact Carla Slepak of

this office at (818 ) 551-2959 .

Sincerely ,

Philip B . Chandle r

Supervising Hazardous Substances

Engineering Geologist

Facility Permitting Branch

S

Enclosures6

cc: See next page

15 KL

rYM

HDMSe00165886

1.r . Randy UeshiroJanuary 22, 1996Page 2

cc: Mr . Phil Rutherford

Manager, Environmental RemediationRocketdyne DivisionRockwell International corporation6633 Canoga AvenueCanoga Park, CA 91309-7922

Mr . Tom Kelly (H-3-2)

U .S . EPA, Region IX

75 Hawthorne Street

San Francisco, CA 94105

Mr . Jim Ross (w/o attachment )L .A . Regional Water Quality Control Board101 Centre Plaza DriveMonterey Park, CA 91754-215 6

Mr . Ed Bailey (w/o attachment)California Department of Health ServicesRadiologic Health BranchP .O . Box 942732

Sacramento, CA 94234-7320

ROCKWELL, SANTA SUSANA FIELD LABORATORYRCRA FACILITY INVESTIGATION WORKPLAN ADDENDUM , MARCH, 1995

NOTICE OF DEFICIENCIE S

GENERAL 'COMMENTS :

The list of analytes for each Solid Waste Management Unit

(SWMU) or Area of Concern (AOC) must be determined based onthe specific chemical usage and waste handling practices at

that unit . Compounds may not be eliminated from

consideration simply because they have not previously been

encountered at highly elevated concentrations. The field

action levels may not be used to eliminate chemicals from

consideration .

All SWMUs eliminated from the RFI Investigation Phasebecause they were evaluated under an accelerated programmust be presented and evaluated in the RFI Report . Thelevels of contaminants must be compared to background valuesand evaluated using the approved risk assessment protocols .

Any chemical constituents which were handled at a RCRA unitor may have migrated to the RCRA unit but not included in

the closure plan must be evaluated in the Workplan . A

sampling plan to determine if the chemical constituent is

present in the soil will be required if the constituent is

not addressed under a different overlapping SWMU .

All soil vapor probes for the active survey need to beinstalled to an appropriate depth to avoid atmosphericdilution . Generally, probes need to be installed to atleast five feet below ground surface (bgs) . However, ifthis proves impossible due to shallow bedrock, the probesmust be sealed with bentonite and protocols using low purgevolumes and flow rates followed to minimize possibl e

latmospheric break-through .

The scope of passive soil vapor sampling should be re-

evaluated . Since contamination has already been identified

in most of the areas under consideration, and the primary

value of the passiveor flux measurement technique is as a

qualitative screening tool, the data produced would not

provide substantial new information . The flux measurement

should only be employed in those specific instances where

site conditions would limit the use of active sampling or

where it would provide data which could not be produced

using active techniques . Instances where passive sampling

would be appropriate would be for the spatial identification

of fractures where dense non-aqueous phase liquids (DNAPLS)

might be lodged under a thin soil cover which could

subsequently be targeted with deep vapor probes set in the

fractures, or low permeability zones where collection of

active samples might be problematic . It is suggested that

HDMSe00165888

additional active vapor points be added to fully evaluatethe distribution of VOC contamination where passive pointsare deleted. Cr. : !

6 . Each SWMU and AOC should be evaluated in a walk-through byDTSC staff along with representatives of Rockwell and Ogdento, decide on final placement of vapor probes and soil matrix

samples .

7 . The Workplan contains no discussion of ground waterassessment. Ground water must be addressed under the RFI,even if as a separate phase of RFI activities . Many of theassessment and production wells located on- and off-site areincluded in the Post-closure Permits, however , a significant

number are not and should be included in the RFI process.

Furthermore, if currently unknown vadose zone sources areidentified in areas where coverage is inadequate or non-existent, additional wells will be required . These wells

would need to be installed as part of the RFI . vr

8 . All above-ground tanks (AGTs) which were used for solvent

storage need to be evaluated during the RFI process, in

order to determine if these tanks have acted in the past as

sources of contamination or are on-going sources . This

evaluation should consist primarily of soil vapor sampling

which needs to extend from each tank along any piping runs

to the test stands where the solvents were used . A complete

listing of all such tanks and appurtenant piping needs to be

presented in the Workplan together with detail maps at an

appropriate scale . In addition , surface drainage leading

from the tanks may need to be included in the investigation .

9 . In addition to providing the contaminant histories for all

wells related to the SWMUs (constituents handled at the

SWMUs or breakdown products ), please provide the following :

hydrographs or the ground water highs and lows which would

indicate the variable thickness of the vadose zone,comparisons of upgradient and downgradient ground water

wells for each of the contaminants which may be related to

the SWMU , and a discussion of whether the SWMU appears to be

the source of the ground water contamination .

10 . The tables included in each individual section contain onlyre-statementsof material from the text of the Workplan .

Additional information , such as specific materials used and

summaries of releases need to be provided

. 11. Facility boundaries must be displayed on all maps depictin g

SWMUs or AOCs, where the units are located in close

proximity to the property line . ,,,,,~ ."0,/ ; -- ,i ( S'__

12 . The use of seismic reflection techniques should b e

considered for use in mapping the fracture system in bedrock

beneath the site , since these fractures have not beenadequately mapped and they provide a significant control on

Pc ,

HDMSe00165889

contaminant migration . The data gathered could then be used

I

1

15 .

1

to focus the investigation which could potentially reduc eoverall costs . At a minimum, Rockwell should conduct a testof this methodology as part of the R PI . ri i -- Tc

It cannot,be assumed that if an agency is overseeing a

potentially present at the SWMU have been fullyparticularSWMU that all the chemical constituent s

investigated- Rockwell must present the list of chemical s

investigated , and the results of the investigation. -c -handled at a particular area, the chemical constituents

DTSC has determined that the risk assessments performed forthe surface impoundments and drainages subject to PostClosure permits are not adequate . Until DTSC has approvedHRA protocol, Rockwell cannot conclude that these SWMUs donot pose a risk to human health . -~'

According to the CCR, the fuel layer on the runof fcontainment ponds and impoundments used to collect runofffrom rocket test operations throughout the facility wa sroutinely burned off . Because these burning conditions

these compounds must be evaluated in the ponds where thiscould produce PNAs and dioxin or dibenzofuran compounds ,

practice may have been used and at any areas where sedimentsLLulu 1.11CJC jJuliu may lldve been empiacea . ~;

S maps presenting sampling results in the RFI Repor tshould be on topographic maps of sufficient scale t o

sample locations .

EXECUTIVE SUMMARY

The field action levels (FALs) proposed to drive the

investigation must be protective of ground water . Some ofthese levels were selected based on threat to ground water,

but when modeling indicated that those levels were not

protective (as in the case of TCE), Ogden and Rockwell

determined that it was acceptable . for ground water to beimpacted for a period of five years . The rationale for thisdecision was that since Rockwell is currently pumping and

treating ground water, any contaminants which would bedischarged would not migrate off-site . First, this fails toacknowledge the fact that VOC contamination has already

migrated off-site and continues to do so . Secondly,Rockwell still does not have a sufficient understanding of

the migration of contaminants in ground water beneath the

site due to the complex fractured bedrock aquifer . If theinvestigation is to be constrained by pre-selected values(i .e ., FALs), then these numbers must be sufficiently

protective to assure that direct exposure is not a concern

and that ground water will not be adversely impacted .

HDMSe00165890

In determining FALs, and in conjunction with health-basedremediation goals, the Workplan must consider thepossibility of metals contamination migrating to groundwater. This is especially so given the shallow nature ofground water at some areas of the site . Although Rockwellasserts that the levels of metals previously detected in theground water are below Maximum Contaminant Levels (MCLs),metals contamination may be present in the soil which hasnot yet migrated to ground water . Additionally, any metalswhich appear in the ground water at statisticallysignificant levels above background, even though the levelsare below MCLs at the present time, could indicate soilcontamination which is migrating to ground water .

The "cut-off" level of 100 µg/l for soil vapor results is

not acceptable, particularly since this number was not keyed

to the specific compounds detected . For example, vinyl

chloride at 100 µg/1 poses a much more significant threat!-,wthan other contaminants at the same concentration .Furthermore, if any fine-grained sediments are encountered,

the 100 Ag/l value in soil vapor would be far lessconservative and the samples would need to be evaluated on

total VOCs, not just vapor concentrations . An acceptablecut-off value for vapor cpnce trations wouldbe 1 1

Surface sediment samples need tobe collected at local baselevels where fine-grained materials would tend to bedeposited. It is not sufficient to go only 100 feetdownstream, nor to stop at the fence-line of the facility .The extent of contamination needs to be evaluated both on-and off-site, based on appropriately conservativeFALs .

SPECIFIC COMMENTS

SECTION 1 : INTRODUCTION

1 .1 Facility Background : Land use of the Brandeis-Bardinproperty should be discussed in this document .Additionally, Brandeis personnel have indicated that cattledrink water produced from water wells located on thatproperty .

Table 1-1 : Summary ofInvestigation for SWMUs and AOCs

The following comments are provided for SWMUs listed in Table 1-1which were not included in the proposed RFI sampling. SWMUsincluded in the proposed Workplan are addressed in latercomments .

4 .1 It is unclear if the underground tank investigation includedTCE testing . Since TCE was used at the test area,evaluation of TCE contamination must be included in the RFIwork to be performed. z , . j

t i

HDMSe00165891

4 .2 Indicate any environmental ( soil, ground water , soil vapor)U-"LP sampling required by Ventura County Environmental Health .

Samples presented* in the CCR were located at the perimeterof the landfill only . Soil vapor and soil samples in thelandfill itself may be warranted .

4 .6 The soil samples collected for VOC analysis were obtained a t0 .5 to 1 foot depth which is within range of atmosphericeffects and not deep enough to establish whether VOCcontamination was present in the soil . This is especiallytrue if the soil has been disturbed during excavationactivities . Additional deeper soil samples or soil vaporsurvey should be ,conducted in this area . ,

4 .12- .13 Some concentrations being reported previously below th ecr-i action levels alone are not an adequate reason to forgo

defining the extent and maximum concentration . If Rockwellmaintains that no additional samples are needed to definethe extent of contamination , Rockwell must demonstrate thatthe extent of contamination has beenadequately defined inthe Workplan. The results of the confirmatory samples forthe accelerated cleanup must then be included in the RFIreport and included in the background and health basedcomparisons.

4 .14 Soil vapor sampling should be expanded to include the tes tstand and spillways if not already done in a separateinvestigation .

r

4 .16- .17 Provide the results of any and all sediment or soilsamples collected from the R-1 and Perimeter ponds in theWorkplan . Justification for not recommending furthersampling in these ponds is necessary since the singl esediment sample previously collected in each pond may

enough to adequately characterize the VOC and metal

n t b

concentrations in the entire pond .

AOC : Area I Leach Fields : Building 359 Leachfield/drainage

Present any investigation of the drainage and sump at

building 359 . The sump and drainage from the building may

need further investigation . Solid rocket propellent was

stored in this building .

AOC : APTF Tanks

According to the CCR RP-1, NTO, hydrazine was contained in

tanks in these areas . The soil surrounding the tanks shoul d

be analyzed for all the constituents stored in the tanks .i

5 .1 See comment 4 .2 above . This SWHU should be fully

characterized . ^J ,

5 .6 Soil samples should be taken downslope from the former ash

pile where rainfall run-off would tend to collect and

HDMSe00165892

sediment be deposited . Since two samples may not beadequate to f•!lly .characterize, this SWMU, samples should beproposed . l r

5 .7 The waste coolant tank was not included in the closure plan(CP) submitted to DISC . nr ,,l

5 .14 Indicate if the Bravo Waste Tank is included in the Post-CPfor the Bravo Drainage Area . Characterization of the areabeneath the tanks may be warranted

5 .18 Metals were not analyzed at this SWMU . Describe therationale for leaving this analysis out of the samplingplan . Characterization of metals maybe warranted at thisSWMU . A t. ~ r . _ ,,C_ ,= : ,' r

5 .19 The sample resultsfrom previous sampling events must beincluded and evaluated in the final RFI report (see GeneralComment #2 above) .

5 .23 All chemical constituents used or generated at this areamust be included in the investigation . It appears that BNAsand fluoride were used but no analyses have been performedfor these constituents .

5 .26 Because these pondsand drainages collected runoff fromrocket testing/cleaning operations, analysis for dioxins(due to burning fuel on top of ponds ) and SVOCs i snecessary .

AOC : Building 515 :

Present any soil or soil vapor samples conducted inconjunction with the NPDES permit . This area should becharacterized for all the chemicals handled at the building .

6 .3 Soil vapor sampling has not been conducted at this unit andmay be warranted based on the past chemical usage .

6 .8 The number and location of samples obtained appear to be

inadequate to represent the large area contained in the

Silvernail Reservoir . Further sampling, therefore, may bewarranted . Additionally, NPDES permit requirements do notaddress threat to ground water beneath the unit and do not

address the threat to humans contacting the sediment fromthe reservoir . The correspondence with the Los AngelesRegional Water Quality Control Board (LARWQCB) did not

indicate that threat to ground water from individual

chemicals such as arsenic was considered .

6 .9 The results of the accelerated cleanup must be included inthe RFI report . The cleanup is subject to the approvedhealth risk assessment .

HDMSe00165893

7 .2 The VOC contamination beneath Building 133 must be assessedas part of the RFI process or the CP must be amended toinclude assessment of this plume . The current CP does notaddress VOC investigation .

7 .3 The RCRA Facility Assessment (RFA) Report indicates thatlarge components were buried west of the disposal pondbetween two large bedrock outcrops . Results of any soil

sampling in this area should be included in the Workplan . Asoil sampling plan must be proposed as part of the Workplan .Also , see General Comment #2 above.

It appears that all not all the chemicals (PAHs),radiological parameters and chemical byproducts (dioxinshave been fully assessed in this area . These must beaddressed as part of the Workplan .

Metals, VOCs, TPH were discovered during the limitedinvestigation . The DOE jurisdiction does not addresschemical contamination , therefore the extent o fcontamination from these constituents must befullyaddressed in the Workplan . Additional soil sampling toassess the extent of contamination should be included in theWorkplan if necessary to determine the extent ofcontamination .

7 .8 All chemicals, not just petroleum hydrocarbons, handled atthis area must be assessed during the RFI process .Additionally, if drums containing unknown constituents werepresent, as hasbeen suggested in the CCR, a full suite ofchemicals must be investigated .

7 .9 Based on the usage of organic solvents in this area, and thelimited soil sampling conducted (3 samples), a soil vaporsurvey is warranted .

7 .10 Include the results of this investigation in the RFI reportso any results above background can be evaluated in . thehealth risk assessment .

SECTION 2 : DETERMINATION OF FIELD ACTION LEVELS (FALs)

2 .3 .1 Exposure Pathway Analysis and Potential Receptor s

1 . The evaluation of exposure pathways needs to consider theairborne pathway relative to the transmission of dust,gasses, vapors , etc ., whichmay have emanated from thefacility and moved off-site .

2 . It is stated that the pathway for the off-site ingestion ofimpacted ground water is uncertain due to the "hydrauliccontainment afforded by the ground-water treatment system ineffect at the SSFL ." This statement suggests that some ofthe ground water data previously collected was not fully

HDMSe00165894

evaluated during preparation of the Workplan, since off-siteprivate wells have been found to be impacted by site-derivedcontaminants . This pathway must be considered complete forthe purposes of risk assessment, although it must be notedthatthe full extent of off-site contamination has yet to bedetermined .

Exposure calculations must consider a residential scenario .It cannot be assumed that the site will continue to berestricted to industrial use .

The health risk assessment must also consider ecologicalreceptors . Lack of existing data on the species located onsite and the range of these species warrants furtherresearch and cannot be a reason to exclude these receptorsfrom consideration .

2 .4 .2 Ground Water Protection

It is not appropriate to dismiss continued impact to groundwater based on the fact that the pump and treat system is inplace at the site . The RFI makes the assumption that allcontaminants will be captured before they migrate off-site .This contention is unsupported since there has been nodemonstration of containment and site-derived contaminationhas already been detected in off-site wells . FALs whichallow continued discharge of contaminants to ground waterare not acceptable . Furthermore, costs associated with pumpand treat operations are~~ fAA~,r~ greater than those for VOCvadose zone remediation the RFI should be focused on theidentification and remediation of vadose zone contaminationbefore it reaches ground water .

The FALs proposed for compounds which are listed but

evidently never fully evaluated are unacceptable .Specifically, compounds such as cis-1,2-dichloroethylene

(c-1,2-DCE) and trans-l,2-dichloroethylene (t-1,2-DCE) have

maximum contaminant levels below 10µg/l but FALs of 4,000mg/kgand 8,1000 mg/kg respectively . These FALs totallyfail to protect ground water, and it is inappropriate for

them to be less protective than those for other compoundswith similar health risks such as trichloroethylene (TCE)and perchloroethylene (PCE) . All FALs need tobe revaluatedfor a number of reasons, which include the fact that site-

derived contaminants have already migrated off-site, some

exposure pathways were not considered, and many of the

break-down products are more toxic than the parent compounds(i .e . vinyl chloride ) . The LARWQCB attenuation factormethodology may also . be used in conjunction with healthapproved health risk assessment protocols to insure thatFALs are protective of ground water .

HDMSe00165895

SECTION 3 RFI FIELD IMPLEMENTATION

3 .1 .1 Passive Soil Gas Sampling

As stated previously, the use of passive soil vapor samplingtechniques would not appear to be necessary for much of thesite . Rockwell has previously expressed concerns regardingVOC migration from ground water resulting in erroneou sinterpretations that vadose zone contamination was present .Given the greater sensitivity of cumulative flux measurementtechniques, this would be much more of a possibility whenusing passive samplers .

Passive soil vapor sampling should be used only in thosespecific instances where site conditions would limit theeffectiveness of active techniques . The following twoinstances are provided as examples, although there may beother cases where the flux measurement technique wouldprovide useful data .

In instances where semi-VOCs would be reasonablyexpected to be present based on chemical and wastehandling practices it may be reasonable to use the GoreSorber or an equivalent system if it could identifythose specific semi-VOCs in question .

For those areaswhere very little sediment is present(i .e ., less than 3 feet), passive samplers could beused to avoid the problems related to atmosphericbreakthrough associated with the active technique .Spatial distributions derivedfrom the passive datacould then be used to target specific fractures wherefree or DNAPL phase solvents might be present. Deeperactive sampling could then be conducted within thosetargeted fractures .

In other cases where no specific rationale can be

provided to support the use of flux measurement

sampling, active techniques should be employed . Therole of flux measurement sampling may be increased ifRockwell demonstrates the field efficacy of thesetechniques at the SSFL .

3 .1 .2 Active Soil Gas Sampling

Additional active soil vapor points will be required if thepassive survey is deleted as suggested . These will beneeded to fill data gaps and to fully delineate the extentof VOC contamination. These data will be more useful thanthe passive data, since it will be quantitative . Therefore,the need for additional sampling can be made in the fieldbased on review of the data in conjunction with DTSC staff .This will eliminate, at least to some degree the need togrid large areas, and may ultimately prove to be less costlythan the combined passive/active proposal .

The selection of 100 µg/a as a "cut-off" for total VOCs isnot acceptable . For example, where more toxic contaminantssuch as benzene or vinyl chloride might be encountered as asignificant portion of the contaminants present, or wherethe results do not allow source areas to be adequatelyseparated . Decisions regarding the need for additionalpoints should be made in conjunction withDTSC staff, but asnoted previously, a more appropriate cut-off would be 1gg/1 . FALs should be compared to numbers derived from theLARWQCB Attenuation Factor Methodology in order to assurethat they are adequately conservative .

3 .1 .3 Soil Sampling and Field Test Kit s

The diameter of the direct-push sample to be used for soilmatrix sampling is not specified inthe Workplan . Due toVOC losses which can occur due to friction, heating, andsubsequent volatilization, the diameter of the samplershould be maximized (minimum 2 inch diameter) . Furthermore,the analytical laboratory shouldbe instructed to collectaliquots from the center of the sampling sleeve .

The proposed FALs are not acceptable, because, in additionto the comments on section 2 .4 .2 above , they are notcalculated using DTSC accepted health risk assessmentprotocols. (See the attached memo from TR Hathaway .) Afterrecalculating the FALs in accordance with approvedprotocols,the soil screening level of 100 mg/kg TPH mustalso be re -evaluated.

The full extent of contamination must be defined under theRFI process . Just because a water body is under an NPDESmonitoring program, does not mean that dischargesinto orout of it can be ignored . Results of previous sedimentsampling must be provided or additional sampling proposedfor the water bodies in question, and other samples may needto be collected down-stream of these bodies .

In cases where contamination extends off-site, the extentmust be fully evaluated . Samples in drainages must becollected based on observations of stream flow andsedimentation . Samples may not simply be collected at pre-selected distances down-stream of a unit, nor at thefacility boundary . Sediment samples are also needed atlocal base-levels where fine-grained sediments would belikely to drop out of suspension and be deposited . Theseareas are likely to be off-site in many cases .

The extent of contamination should be defined based onappropriately conservative FALs or non-detects for nonnaturally occurring compounds , especially where thosecontaminants may have migrated off-site and a more rigorou sevaluation is being requested by the affected party .

10 -

HDMSe00165897

3 .1 .4 Background Soil Sampling

1 . Background samples for metals need to be collected away fromand up-slope of any SWMUs or AOCs . Furthermore, thesesamples need to be collected at depths greater than theproposed 0 to 6 inches in order to avoid any effects due toairborne transport of contaminants . The proposal to collectbetween ten and twenty background samples may be acceptable,but the number of samples must be sufficient for th estatistical evaluations proposed in the Workplan .

2 . The need for metals analyses needs to be based on the usageof chemicals and storage of wastes at the SWMU or AOC inquestion . Analyses for certain metals cannot be deletedbased on artificially high FALs not having been exceededduring any previous sampling . The RFI needs to define theextent of all contaminants through the selection of FALswhich are appropriately conservative . For example, FALswhich exceed STLC or TTLC values are not acceptable .

3 . Explain the rationale for collecting background samples at0-6 inches depth . Background samples collected at a minimumdepth of 12 inches may be more appropriate to decrease thelikelihood of airborne soil contamination . If samplescannot be collected at that minimum depth in an area becauseof the shallow depth to bedrock, the sample should berelocated .

3 .2 .3 Offsite Laboratory Analysis

1 . If the decision is made to perform passive soil vaporsampling as a precursor to the active vapor sampling, andNERI is chosen as the sub-contractor to perform this work,all analyses must be conducted using the full ga schromatograph/mass spectrometer (GC/MS) methods . Thestandard Petrex analyses (i .e ., MS only) will not beconsidered sufficient .

Table 3 -1 Decision Level II : SSFL RFI Field Plan

1 . The statement that ground water sampling is being conducted

under a separate, concurrent environmental program is notentirely accurate since all monitoring points are not

included under the two Post-closure Permits issued for thesite . Furthermore, Area IV is not addressed at all underthese Permits . Ground water issues need to be fully coveredunder the Workplan, particularly for those wells or areas

not addressed by the Post-closure Permits .

2 . The proposal to collect active soil vapor samples fromdepths as shallow as two feet is not acceptable . Typically,the minimum acceptable depth for this type of sampling isfive feet . However, it is understood that there may beshallow bedrock locations at the site where 5-foot samplingis impossible . In these instances, special precautions must

MOMMHDMSeOO165898

be taken to assure a low purge volume and that the sampleprobe is adequately sealed from the surface to the top ofthe sand pack in order to reduce the possibility o fatmospheric air being drawn into the probes . The use ofnon-toxic tracer gasses introduced at the surface around theprobes is suggested as a meansof demonstrating that leakageis. not occurring .

Table 3-2 Analytical Categories For Potential ChemicalsWastes

PCDDsshould also be analyzed in areas where solvents wereburned such as run-off control basins downslope of rockettest stands .

SECTION 4 --PILOT TESTING METHODS AND IMPLEMENTATION

DTSC did not review the Remedial Technologies (Section 4) ofthis Workplan . The remedial technologies proposed for pilottesting will be evaluated during the Corrective MeasuresStudy phase of the Corrective Action Process .

SECTION 5 - PROPOSED FIELD SAMPLING AND ANALYSIS - AREA I

5 .1 - Instrument Lab Hazardous Waste Tank, Building 324, and

Equipment Lab 1,1,1-Trichloroethane (TCA) Distillation Unit andUsed Product Tank, Building 30 1

The Workplan indicates that fuel tank assessments for thesite are being handled by Ventura County, however, no

discussion is provided regarding oversight for the 3,000gallon TCA/TCE underground tank which was removed in 1987 .Given the date of removal, it is highly unlikely that any

vapor assessment work was performed in connection with thisremoval . All data relating to this tank removal should be

provided in the Workplan, and proposals for vapor assessment/"work included as well .

With respect to the other on-site underground tanks being

overseen by Ventura County, all assessment data relating to

these tanks needs to be included in the Workplan .Particularly, include the types of chemicals investigated in

conjunctionwith the UTGs . The types of chemicals

investigated must match the types of chemicals stored in the

underground tanks during the entire life of the undergroundtank .

The area of the 200-gallon l,l,1-TCA spill needs to be fullyevaluated .

The soil vapor sampling grid in the vicinity of SV-4 .3-3 andSV-4 .3-5, where high VOC concentrations were previously

reported, needs to be more tightly spaced to adequately

define spatial patterns and to determine thesource for the

contaminants detected here .

- 12

HDMSe00165899

More than the five proposed semi-permanent probes may berequired to provide adequate coverage during a vaporextraction remedial program . It is suggested that whereverpossible, probes be installed in a semi-permanent manner toavoid the need for later duplication of this work .

Because, according to the CCR, a rocket test area may havebeen located near Building 436 and Building 324 was used asa machine shop,_a metals analysis should be conducted inthis area .

5 .2 - LOX Plant Former Sump and Clarifie r

The proposal for collection of soil vapor samples from adepth of 1-foot bgs is not acceptable due to probableatmospheric breakthrough and dilution. It appears that thesump and clarifier previously located in thisarea wereinitially installed to a depth of 10 to 12 feet bgs andtherefore, a sufficient thickness of soil should be presen tto allow vapor samples to be collected from below the bas eo e un1 s . / ,r

•

As stated previously , the down- stream locations for sedimentsample collection must be selected based on where fineswould be likely to drop out of suspension . Pre-selecteddown-stream locations are only appropriate in cases wherethey coincide with these areas of deposition .

5 .3 - component Test Laboratory

Data from the underground tank removal in this area needs tobe presented and evaluated . {~ r

The Workplan should describe where all activities such as

engine testing and waste run-off occurred in this area . Theexact dimensions and orientation for the spillway need to be

presented along with its point of origin . The use for eachbuilding during each time period needs to be discussed .

The storage and use of TCE mustbe more fully described .Specifically, any tanks used for storage along with pipingruns need to be evaluated with soil vapor sampling .

All former test stands need to be identified on the maps ofthe area . „ , t ,

The previous sampling which did not reveal significantdetects for fluoride, chloride, or nitrate in the vicinityof the test stands and pond reveal nothing aboutcontamination which may be present as a result of thesubsequent laser testing in this area . Both soil vapor andsoil matrix samples need to be collected to evaluate ifdischarges of NaOH, hydrogen peroxide, n-heptane, or Freonresulted from the use of these compounds during the lasertesting operations .

13

HDMSeOO165900

6 . Soil vapor sample points must be located along the formerspillway .

7 . Dioxin and PNA sample(s) should be collected in the pond .See discussion in General Comment #13 above .

8 . In all cases where physically possible, vapor probes shouldbe installed semi-permanently to allow remediation progressto be monitored .

5 .4 - Bowl Area & 906 Leachfiel d

Building 906 was not identified on the figure for thissection . Furthermore, the document does not indicate ifleachate was only received from this building, or ifdischarges from other buildings were directed to thisleachfield .

Although it is indicated that acetone is a common laboratorycontaminant, it is not clearly stated if it was specificallyidentified by the analytical laboratory as such in thi scase .

There does not appear to have been sampling conducted in

this area for semi-VOCs or PNAs, which could have been

associated with the coal gasificationand pond burningactivities . If this sampling has been conducted, the

results must be presented for review, if not, the possible

presence of these compounds must be evaluated throughadditional sampling under the RFI process .

The Workplan must propose sampling for cobalt, lead, zinc,and mercury in the skim pond and leach field . These metalscannot be dismissed simply because previous sampling has notrevealed concentrations above the FALs . The full extent ofall contaminants needs to be evaluated in the RFI . ~,-

There are currently no wells at the site to monitor, for

ground water releases from the retention and skim ponds .noted previously, specific ground water elements to deal

with issues such as this need to be included in thi sWorkplan or as a subsequent phase of RFI work . .

6 . The Workplan does not propose sampling in or around eitherthe test stands or the retention pond . The document musteither justify the lack of sampling in these areas o rpropose adequate characterization activities .

The number of soil vapor locations previously sampled, donot provide sufficient coverage to limit this phase oftheinvestigation as severely as proposed . Additional samplingunder the RFI needs to be proposed , such that the fullnature and extent of contamination can be reasonablyevaluated .

14

HDMSe00165901

5 .5- Happy Valley

1 . The extent of Freon contamination in the Tunnel Facility hasnot beendefined . The 800 µg/l detected in one sample is anindication that significant contamination may exist in thisarea ; the two proposed additional samples will probably notbe . sufficient to define the extent .

The Workplan does not clearly state if the Thermal Treatment

Facility and Tunnel Facility only treated wastes fromBuilding 372 or if wastes from other buildings were alsotreated . This issue needs to be clarified, and additional

sampling/analyses proposed if other waste streams werehandled in this area .

The nature and extent of all metals contamination must bedefined , not just arsenic .

Sediment sampling needs to address all contaminants whichcould have been released from the AOC or SWMU, not justthose contaminants previously detected .

As stated in previous sections, downstream samples need to

be collected at specific locations where sediments would be

expected to be deposited, not at pre-selected distances fromthe AOC or SWMU .

The Workplan fails to address the areas used for storage ofnew chemicals and fuels . All tanks, dispensers, pipingruns, etc . must be included in the RFI process andappropriate sampling proposed .

SECTION 6 PROPOSED SAMPLING AND ANALYSIS AREA I I

6 .1 - FinalELV Assembly, Building 20 6

It is stated that the contents, size, or use of theunderground tank formerly located in this area are unknown,however, no sampling is proposed . Given the uncertainnature of this unit, work including afull suite of analysesmust be performed here .

Itis noted that significant VOC concentration were detectedin both soil vapor and soil matrix samples collected in theimmediate vicinity of the PCB storage building (currentlyundergoing closure) . However, no additional sampling forVOCs is proposed either under this RFI or under the RCRAClosure . The presence of VOCs in this area must beaddressed under one of these programs .

The full nature and extent of all contaminants must bedefined and sources delineated ; FALs may not be used to

exclude areas from further consideration or to eliminateanalytes . 11

15

HDMSe00165902

Downstream sediment samples must be analyzed for allconstituents of concern, including PCBs, and the sample scollected at appropriate locations as described previously .

6 .2 - Alfa Area

1 . The Workplan fails to address the areas used for storage ofnew chemicals and fuels . All tanks, dispensers , pipingruns, etc ., must be included in the RFI process andappropriate sampling proposed .

2 . It is not indicated if any semi-VOC analyses were previouslyperformed on samples from the pond . This is of importancedue to the prior burning practices in this area . II I

3 . Figure 6-5 and the text do not agree . The figure indicatesthat the maximum TCE concentration in this area was 12,000

pg/kg detected in a soil sample collected at a depth of one

foot, while the text states that the highest soil matrixresult for TCE was 670 pg/kg . This discrepancy needs to beresolved .

The statement that ground water contaminant concentrationsdecrease with depth is not supportable, since the groundwater flow regime beneath the site is not yet fullyunderstood due to the fractured bedrock aquifer andtherefore, source areas and migration pathways have not yetbeen defined . The pertinent points here are thatcontaminants have migrated to and impacted ground water, andthat the contaminated ground water has then migrated offsite .

Sediments from Silvernail Reservoir need to be analyzed forall constituents of concern from the Alfa Area .

The number of semi-permanent vapor probes needed to monitorremediation will almost certainly need to be greater thatthe 4 - 6 proposed . Whenever possible, all vapor p-robesshould be installed as semi-permanent to avoid needlessrepetition of work.

7 .' No additional characterization is proposed for the highlycontaminated surface sediments . These materials need fullycharacterized and remedial measures proposed such that thethreat to surface and ground water is eliminated .

6 .3 - Bravo Are a

1 . The work performed or to be performed in the drainage

channels under the Post-Closure Permits must be fullydescribed . If this work is not comprehensive ( ie . chemicalconstituents which may have been deposited or migrated tothis SWMU but are not addressed under the Post-Closure

Permits) or the risk assessment requires additionalinformation, additional sampling will be required .

16 -

HDMSe00165903

Sampling in drainages cannot be excluded because ofSilvernail Reservoir . Samples from both the drainages andthe reservoir a--e- needed .

Because the areas upgradient of the ponds may have generatedmetals which could drain to the skim ponds, sediment in theskim ponds must be analyzed for metal contamination .

Soilvapor characterization of the skim pond must beincluded in the Workplan . Although previous sampling didnot reveal VOCs in the pond , one soil vapor sample is notenough to characterize the skim pond and soil sedimentsamples for VOCs cannot be relied upon .

Fully characterize the extent of fuel contamination in thebedrock beneath the spill which took place on July 21 ,in the Bravo Test Area .

1995,

6 .4 - SPA Area

Activities being undertaken for the drainages andimpoundments under the Post-Closure Permit must be fullydescribed . Additional work may be required in these areas .

It appears that a typographical error exists in Table 6-4where it is stated that additional soil gas work will not bperformed if the passive soil vapor results are less than100 Ag/l total VOCs . The table should be corrected to readactive soil vapor results and the limits on vapor levelsreduced to 1µg/l-

SECTION 7 - PROPOSED FIELD SAMPLING AND ANALYSIS - AREA III7 .1 - ECL Area

Run-off from this area cannot be discounted due to thepresence of the R-2 Ponds . The full nature and extent ofcontamination must be defined .

Because an adequate health risk assessment protocol has not

been approved, soil samples cannot be discounted becausethey are below a predetermined limit . The full nature andextent of contamination must be determined and the

acceptable limits which are protective of human health andthe environment will be determined based on thatdetermination .

3 . Additional soil and soil- vapor'samples beneath the pipelinesleading to the ECL Collection and Run-off Tanks and buildingleachfield may be needed to fully define the extent o fmercury and VOC contamination .

7 .2 Compound A Facility

1 . The chemicals used in fluorine gas production must be fullydocumented, and additional sampling proposed as appropriate .

17

HDMSe00165904

2 . Although there is no indication of the history of activitiesin the storage shed located in this area, a statement ismade that there were no releases here . If the history ofthe area is not documented, sampling will have to beperformed . 1 1

3 . The non-detectable concentrations of TCE reported forproduction well WS-11 do not demonstrate that releases toground water have not occurred in this area . Due to longscreens and associated dilution effects, productions wellsare not good indicators of actual contaminants present inground water .

All active soil vapor samples need to be collected atminimum depths of 5 feet bgs,or precautions taken to assurethat atmospheric dilution is not occurring .

5 . More than two semi-permanent vapor probes will be requiredin this area to adequately monitor remedial actions .

7 .3 - STL-IV Test Area

1 . The work performedor to be performed in the drainagechannels under the Post-Closure Permits must be fullydescribed . If this work is not comprehensive, additionalsampling will be required . The samples must be evaluatedusing aHRA protocol acceptable to DTSC in accordance withthe comments in the attached memo from T .R . Hathaway toCarla Slepak . The location of the drainage channels is notapparent in figure 7-7 map of the area .

2 . All active soil vapor samples need to be collected atminimum depths of 5 feet bgs, or precautions taken to assurethat atmospheric dilution is not occurring .

SECTION 8 - PROPOSED FIELD SAMPLING ANDANALYSIS AREA IV8 .1 - Building 56 Landfill

The work plan states that the ground water contamination

identified in this area did not result from activities here

however, no rationale or explanation of the source areprovided . The Workplan must provide an explanation of thesource for the observed ground water contamination .

No information regarding analyses forTPH , metals, or TCE inwell RS-16 is provided . Without these analytical results,there can be no conclusions regarding lack of impact toground water from activities in this area . .r r : .

The use of radiation badges suggests the presence of

radioactive materials in this area, but there does not

appear to be any analytical work proposed to evaluate thepresence of such materials . This must either be explained,

or additional sampling/analyses, such as gamma ray

spectrometer work, proposed .

18

HDMSe00165905

All geophysical anomalies need to be investigated andtrenching conducted at the locations of these anomalies .

A discrepancy exists between the text of this section, whichstates that no diesel contamination was identified, andFigure 8-2 which indicates that 500 mg/kg of diesel wasencountered in soil sample LF-6 . Either the text or thefigure need to be revised .

Indicate the drum storage location on figure 8-1 ,

SECTION 9 SUMMARY OF DATA NEEDS

Revise the numbers of samples required and the areas wheresamples will be collected in this section as necessary toreflect the changes required in the above comments .

SECTION 10 RFI DATA ANALYSIS

10 .1 .1 Background Concentrations

1 . Indicate the locations where background samples will becollected . Explain the rationale for selecting the locationincluding a description of past practices at or near theselected site, practices, tanks or structures wherehazardous materials were handled located upgradient from thesample location . Areas which may have been impacted by SSFLpast practices will not be indicative of true background .

See comments to section 3 .1 .4 above .

10 .2 SWMU and AOC Risk Assessment Approach

See attached memorandum from T .R . Hathaway to Carla Slepak .

SECTION 12 RFI PROJECT MANAGEMENT AND SCHEDULE

Figure 12-1

The DTSC Project Director is now Philip Chandler .

Figure 12- 2

Submittal deadlines must concur with any timelines in thePost-Closure Permits .

APPENDIX D HEALTH AND SAFETY PLAN

See attached memorandum

19

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01/17/96 15 :33 FAX 916 327 2509 OSA DISC ... REG3PERi&IT / S&E Z002/00 6

STATE OF CAF IFORNI A

(916) 323-375 5

"DEPARTMENT OF TOXIC SUBSTANCES CONTROL40 Street

ox 806mento, CA 95812-080 6

Voica cFax : (916 ) 327-250 9

FROM: Y VM, MS, DABTltff oxi to st

fl4thc of c Affairs (OSA)and Ecological Risk Section (HERS)

DATE :

IVIRONMENTAL PRO F .TION A ENC Y

MEMORANDU M

Carla Slepak, Project ManagerHazardous Waste Management BranchDepartment of Toxic Substances Control (Region 3

January 17, 1996

PFTE WILSON ,ov mrr

SUBJECT Review ofHRA Portion ofRCRA Facili .yy Investigation Workplan AddendumSanta Susana Field Laboratory (Rockwell / R.acketdyne)PCA Code: 25 120 Site Codes : 300381, 300122 , 300232'Workphase : 33 MPC Co-de- 37

Background

The Rocku e11 International Corporation has pe. formed aerospace - indust ry research,

including development , manufacture, and testing of space. and propulsion units and par's at the Santa

Su_Sana Field Laboratory (SSFL) since 1945. The primary wastes associated with these activities are

liquid rocket test fuels, solvents, metals, and oxidizers .

The total area of the SSFL facility, which is located approximately 5 miles west ofChatsworth is approximately 2700 acres . The facility has been divided into five administ arive areas

(Areas I - IV plus a 1200 acre Buffer Zone) .Two groundwater systems, tivluch are hydraulically connected have been iderin fied .

Approximately 200 monitoring we'ls and a groundwater r e mediation system have been installed .

Contamination of both ground\;~water systems has been reported .AResource Conservation and Recovery Act (RCPA) Facility Invcsti ation (FYI) wori ;plan

was o riginally prepared by_ICF Kaiser in 1993 . The documents currently re iewed incorporate

DTSC comments (letter from Alan Sorshcr, June 30, 1994) relative to the original woricplan anc

provide further detail regarding the RFI sampling plans . These documents (Addenda Vols . I & U)

are intended to supersede the o ; ig Sal work Ian (Vol. I, page ES-1) .

HDMSe00165907

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Carla Slepak - Santa Susana Field Laboratory (RFI Workplen)January 17, 1996

Page 2

Documents Reviewe d

The documents, "RCRA Facility Investigation Workplan Addendum Santa Suwa FieldLaboratory Ventura County, California (DTSC Review Copies - Volumes I & II" were prepared b )Ogden Environmental and Energy Services for Rockwell International Corporation (RocketdyneDivision), the National Aeronautics and Space Administration, and the U .S. Department of Energy .These documents are dated March, 1995 .

Scope of Review

The Project Manager requested review of the HRA section (Section 10 - RFI Data Analysisand Section 2 - Determination of Field Action Levels) of the RE workplan . The sections werereviewed for scientific content . Nfnor grammatical or typographical errors that do not affectinterpretation have not been noted . However, these inaccuracies should be corrected in the finalversion of this document . Any future changes or additions to the document should be clearly

identified .

General Comments

Direct-exposure Field Action Levels, defined as the level of cont aminan t which results in a

hazard quotient of unity or a target risk level of 10 '6 , may not be used to eliminate organic chemicals

from the quantitative risk assessment (QRA). These levels are, also, unacceptable for use in the

initial determination of the need for further actionat the site, since they do not correspond to values

calculated using PEA or RAGS equations and approved parameters . Other (i. e ., site-specific)

parameters may be utilized in later stages of the risk assessment which allow for more refinement,

however, they may be not be used to calculate screening levels .

Quality assurance procedures must be documented for samples used to establish background

concentrations .

Speciation of chromium in maximum onsite samples prior to comparisons with background

levels is recommended to provide assurance dal Cr(T) levels do not contribute to potential

carcinoeenic risk .

The subject wockplan addresses (Section 2 .3 .1, Section B 6 of Appendix B, and Figure 2 .3)

the following exposure scenarios :

1 . Onsite exposure of industrial workers to contaminated soil via incidental ingestion,

dermal contact and inhalation of particulates or vapors. Potential exposures of

industrial workers to groundwater contaminants must also be considered . Continued

operationof the groundwater treatment system for an additional five years must be

supported .

HDMSe00165908

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Carla Slepak - Santa Susana Field Laboratory (RFI Workplan)Janua ry 17, 1996Page3

2_ Exposure of future onsite residents to contaminants in groundwater is addressedby consideration of fate and transport of organic contaminants. Cumulative exposureof residents via the air and soil pathways is not addressed . Page 10-10 indicates thatCALTOX will be used to predict potential groundwater concentrations at theproperty line . Appendix B (page B-6) reports that the direct-exposure action levelsfor each chemical will be entered in CALTOX as a soil concentration and th e

t t T .+'tl 1 1 J . Jpredicted grounawater concentration ki ante b-1) will oe compares to a si d,,ru,i. e., the Maximum Contamination Level (MCL) . Direct exposure action levels ofonly TCE are predicted to be above the MCL at any point in time (Figure B-2) .

The OSA recommends utilization of formulae and default parameters for aresidential exposure scenario which includes a potential groundwater pathway for

future onsite residents . Applications of CALTOX for fate and transport modelingmust be evaluated by OSA and any non-default parameters utilized must be justified .Future sources of water may be impacted and risk to surrounding communities and

tofuture residents must be assessed if toxicologically relevant levels of contaminantsare moving offsite in groundwater .

Specific Comments

1. SECTION 2 (Vol . Wand Appendix B (Vol. II) FieldAction Level s

ine quality ordatawhich were us eo to evaiuaz C in U- neru iai it -1 :-) a~cu rL' u nc ic,r leek /has not been evaluated. Detection levels must be low enough to detect toxicologica lly significantconcentations. Data quality for samples used to establish background levels must be adequatelydocumented . Please provide adequate QA,/QC documentation for the background samples andindicate the number and location of samples which will be utilized in comparisons with onsite sar-Iples

2 . SECTION 2.3.1 Residential scenarios have been omitted . DISC recommends that a residential

scenarios be included at all sites unless a deed restriction is in force (see Specific Comment `4 b )

3. SECTION 10-1.1 Background Concentrations, page 10-1 and Table 2-4

All chromium (Cr) should be speciated to estimate the amount of Cr (VI) present . Or,-sitesamples may contain Cr(VI) and Cr may not be eliminated as a chemical of concern when total Crconcentrations are less than total Cr concentrations in background samples . Cr (VT) is not expectedto occur naturally The OSA recommends that the highest or-sitesamples be speciated to ve'ify the

,.c r' .-r\ m

Paragraph 3, page 10-2, alludes to chemicals of concern which are usua lly referred to by theacronym COC This section states that "IC" - the acronym for indicator chemical - will be use forchemicals of concern . The term `Indicator chemical" implies that exposure to one chemica lrepresents exposure to other chemicals . Please use the acronym "COC" to refer to chemicals ofconcern and , thereby, prevent confusion .

HDMSe00165909

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i

Carla Slepak - Santa Susan Field Laboratory (RFI Wo41an)January 17, 1996Page 4

4. SECTION 10.2.1 Human Health Ris k

. Page 10 -4, paragraph 3, states that ".. .PEA guidance approach will be modifiedcorruiierisurate with available information ." Any major modifications of PEA guidance must beapproved by OSA prior to implementation :

a . Hazard Identification (Selection of Ch micals of Potential Concern , Page 10-4 . Table 10- 1

The listof candidate chemicals of potential concern (COPCs) must include : a) all chemicals

found in materials which are known to have been used or stored at the site, b) possible degradationproducts of these chemicals, c) other specific chemicals identified in samples of all pertinent medi a

co:lectee at inc site, and. a') cnerrIucdls wllltil c (JUIU ou p I C'Scilt as G 1 CSUIL Vl l 1 VJYI Vlll v it iGUVt, u vii iadjacent sites . Sample analyses must utilize methods capable of detecting all candidate chemicals ofpotential concern .

A fist of "indicator chemicals (ICs)" or COCs will be determined for each media at the site

(Table 10-1, Step 2). Please indicate if a separate set of COCs will be determined for each S`" MUor AOC or if a "global" List will be prepared for the SSFL . Estimates of. exposure to individual

COCs may underestimate potential risks and hazards to all chemicals of concern and, as depicted onFigare 10-1, are not consistent with DTSC guidance (Chapter 5- Indicator Cherlicals, Supplemental

Guidance for Human Health Multimedia Risk Assessments of Hazardous Waste Sites and PermittedFacilities, July 1992) . Please identify chemicals of concern using criteria found ir, the previousreference, in Chapter 5 of Risk Assessment Guidance for Superfund (RAGS) Vol I (USEP .A, 1991),

or in the PEA Manual (January, 1994) . Organic chemicals may only be eliminated from the

quantitative ri sk assessment if strong evidence is presented to adequately support the natural,

background occurrence of these chemicals (Section 5 .7 .3, page S-19, RAGS) . In general, ail o gaaic

chemicals must be addressed in the QRA .

Conceptual Site Model . base 10-3

The OSA recommends that concurrence of a DISC geologist be obtained prior t o

elimination of groundwater pathways, as is implied in section 10 .1 .3 .

The conceptual site model considered in this assessment considers only an occupation

scenario . OSA guidance requires that health assessments be based on a residential exposure scenario

(Specific Comment 2). Calculation of risks to future residents dots not imply remediation to levels

w rich would be necessary for residential land use . The rcmediation eoal is a risk managemen t

decision Although a deed restriction which prohibits residential occupancy may be a remedial option,

this option cannot be fully evaluated in the absence of an assessment of potential exposures of Future

residents . Inclusion of a construction worker scenario may be rcasonablc, based on current or faturc

i. nd-use . 'Z,

c Selection Criteria, p~ra ph page 10-6

See comment in "Specific Comment

HDMSe00165910

01/17/96 15 :36 FAX 916 327 2509 OSA DTSC -++ REG3PERMIT,S&E 006%00 8

Carla Slepak - Santa Susana Field Laboratory (RFI Workplan)January 17,199 6Page 5

d Toxici Assessment, page 10- 7

The following order of preference for current toxicity cri teria (Appendix B , Table B-2) mustbe followed. Please revise this section to correspond with DTSC guidelines .

I.) The most recent update of the California Cancer Potency Factors prepared by theStandards and Crite ria Workgroup of Cal1EPA . This database does not includePM s .

II .) U.S . EPA Integrated Risk Information System (IRIS) values .

III.) U. S . EPA Health Effects Assessment Summary Tables (FAST )

IV .) If cri te ri a are not identified in any of these databases , a value may be calculatedfollowing consultation with an OSA toxicologist .

e, Exposure Assessment. page 10- 8

The gen°ra? exposure formula incorporates a variable, i .e., "FC", which implies that exposuremay result from sources other than the site of interest : Other sources of exposure may certainlycontribute to total dosage : however , overall exposure of receptors at this site cannot be reducedbecause of other sources of exposure . Therefore , "FC" would always equal unity .

Paragraph 2, page 10-9, implies that alternative methods of dosage calculation may b eapp ropr ate . Justification must be provided and prior approval obtained for any methodologies wi ciscorThc with current guidelines

f_Dx ros.ire Point Concentrations, Pace 10-1 0

Paragraph 2 - Calculations of potential exposure at the SSFL property line are'essential tocalculation of overall risks and hazards at SSFL ; however, on-site receptors may also be exposed tolevels of volatile chemicals . Pleas : include potential d . .al and inhalation exposures to volatilecompounds identified in groundwater when calculating total exposure of all receptors .

Page 1 C-1 u, paragrapi7 3 - Depth to gr ound'-1,'ater is not a valid c,-iterion fore intiauoo ofthis source as a potential contributor to vapor concentrations in air . Approximately 200 meni Orinwells are in operation at SSFL . Large volumes of water are pumped to the surface for non-potableuses and retained in holding ponds . Additionally, remediation systems do not remove 1O0°/ of thechemicals present . Please include inhalation of contaminant concentrations, which potentially

vaporize from g; oundwatcr, as a pathway in a residential cxpost re scenario .Page 1 0- 11 - Air dispersion models and parameter assumptions, e .g . mixing height = 150

meters, should be reviewed and approved by tnc Ventura County Air Quality Control Dismct .

HDMSe00165911

01%17'96 15 :36 FAX 916 327 2509 OSA DTSC• +•. REG3PERMIT/ SBE 007-'008 '

C.,arla Slepak - Santa Sus-am Field Laboratory (RFI Workplan)January 17, 199 6

Page 6

Exposure Pathway

Results of analytical tests for all chemicals of concern identified in surface water and inshallow zone wells must be reported . The two major groundwater systems at the SSFL have beenpostulated to be connected by fissures . Any chemicals detected in ground water must be consideredas potential chemicals of concern, because additional exposure may occur by inhalation of vapors orby dermal absorption of chemicals deposited on the skin . Additionally, semi-volatile chemicals in soilmay be, potentially, inhaled. Please include all relevant sources of exposure .

h. Intake Rate / Exposure Parameters . Table 10-3

Table 10-3 reports the area of the skin surface for a worker as 2000 cm2/d (sic) . DTSCSupplemental Guidance (September , 1993) recommends 5800 cm2 for hands, neck, forearms, andlower legs .

Table 10-3 reports an estimated ingestion rate for "workers" of 50 mg/day . This mayunderestimate exposure to soil under the conditions existing at this site . USEPA has recommended480 mg/day for construction workers . OSA recommends the estimate of 480 mg/kg for potentialexposures at this site.

i . Direct exposure soil action levels (vol . II Table B-5) and field action levels (vol . I . Table 2-6 )

Soil action levels in this table are reportedly calculated by a formula similar to that used tocalculate LTSEPA Region IX PRGs, however the values differ by up to 2 orders of magnitude, inv thpr rli -& -t- nn Piea c' ralnllatP ,nil crre~.nina levels for P. residential .ccenario that agree with thosewhich arc calculated using the DTSC PEA equations ,

5 . Sections 2 .3 .1 (page 2-5 1 and 10 .2 .2 Ecological Risk Assessmen t

These sections describe an acceptable approach to an ecological screening risk assessmentfor this site according to the guidelines published in "Guidance for Ecological Risk Assessment atHazardous Waste Sites and Permitted Facilities Part A Overview and Part B : ScopingAssessment" Call EPA, Department of Toxic Substances Control, Office of Scientific Affairs,1994-

Conclusions and Recommendations

The current list of `Dir~-t-Exposure Soil Action Levels"(Table B-5) is unacceptable ./n .- .~.. L. .. ..1 .. .-+ 1 .~ ~1 : .++ :r~rea r,-n ..~ tl,o nt2 A t,, ^A nn o e-rmnino ~ ..v~~ an~lvCiC Wl'filPlJl`Q1lll. L-U Ull l.4lJ a11.Lixf 1JVl VV w uvaat Wa..- ~~~ • v~rn• va . u w. .... .a .u .b .v - ....J . .y • . .•..

inorganic chemicals may only be eliminated if levels are below an adequately supported backgroundlevel . The QRA may contain a calculation of background risk for comparison with the onsite risk .

HDMSe00165912

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Carla Slcpak - Santa Susaaa Field Laboratory (RFI Workplan)January 17,1996Page 7

The exposure scenario is unclear . An industrial scenario is utilized throughout most of thedocument; however the groundwater pathway is currently considered only for future residents at theproperty line. The groundwater pathway should be considered complete for offsitc residents, futureonsite residents , and for workers in an industrial scenario:

1

Reviewer: Judith Parker, PhD ., D.A.B.TSenior Toxicologist, HERS

Deborah J . Oudiz, Ph.D.Senior Toxicologist, HERS

c:lssfl roc\rf1wwkplnO117 .h60

HDMSe00165913

STATE lTF CR1Ur ORNIA - ENVIRONMENTAL PROTECTION AGENCY PETE WILSON,Govomo r

DEPARTMENT OF TOXIC SUBSTANCES CONTROLRegion 4245 si Broadway, Suite 425Lorch . CA 90802

4956

M E M 0 R A N D U . M

TO: Carla SlepakHazardous Substances Scientist

Facilities management Branch, Region 3

1011 Grandview Avenue

Glendale, CA 9120 1

FROM : Frank S . ParrAssistant Industrial Hygienist, Region 4Office of Scientific Affairs (OSA)Industrial Hygiene Section (IHS )

DATE : October 23, 199 5

SUBJECT ROCKWELL SANTA SUSANA FIELD LABORATOR YHEALTH AND SAFETY PLAN FOR RCRA FACILITY INVESTIGATIO N

7CA Code : 25120 Site Number :300232r : 33 MP` : 3J

BACKGROUND

The Facilities Management Eranch in Region 3 requested OSA-_ S to review the Health and Safety Plan ( F?=SP) for a RCRA`~ci=!itti inve stigation to be conducted at the RockwellInternational Corporation, Rocketdyne Division ' s Santa SusanaFieldtaboratory, located in eastern Ventura County, California .

Site information included within the HASP revealed the siteis comprised of approximately 2,700 acs-es of mountainous terrainranging from 1,700 to 2,200 feet above sea level . The SSFL issirroundc by Sims Valley to the north, the San Fernando Valleyto the east, and Thousand Oaks to the southwest .

A var_etV C` operations are conducted at the SSFL includ_ngaerospace,inndustrV research, including the development antmanufacture of propulsion units and space units and parts . Laserresearch and development is also conducted at the SSFL _

The scope of work addressed within the HASP includes sitereconnaissance of solid waste management units (SWMUs ) and areasof concern (AOCs) identified throughprior assessment activities

HDMSeOO165914

Carla SlepakRocketdyne RFI HASP

October 23, 1995Page 2

soil gas sampling , and soil sampling employing hand augers andhollow- stem auger drill rigs .

OSA-IHS reviewed the "Health and Safety Plan, RCRA FacilityInvestigation, Work Plan Addendum, Santa Susana Field Laboratory,

Ventura County, California" . This document was prepared by OgdenEnvironmental and Energy Services, Co ., Inc . The HASP was dated

March, 1995 and was received by OSA on October 5, 1995 .

GENERAL COMMENTS

The Department of Toxic Substances Control (DTSC) hasreviewed the HASP for compliance with Title 8, California Code of

Regulations (8 CCR), section 5192 : "Health and Safety forHazardous Waste Operations and Emergency Response" as well as

other appropriate State and Federal Occupational Health andSafety Regulations . Please note that in addition to the

requirements of this section, the employer is responsible for the

implementation of an effective Illness and Injury Prevention

program which is required by the 8 CCR, sections 1509 and 3203 ..The requirements of those sections have not been included in this

review .

An industrial hygienist from the OS T_-IHS may perform a fieldaudit in order to confirm the implementation of the provisions

and specifications presented in the HASP .

The DTSC is unable to foresee all the health and safety

hazards in try work-place by the review of the submitted plan .

Continuous surveillance of the work-site and creation of an

efec e health and safety program by the employer will reducework place in3uries and reduce liability .

CSA-IHS review of this HASP is nut a guarantee that it will

be properly and Safely implemenLed. Is the

emolov°_r's r sponsibility .

SPECIFIC COrg`_ENTS

-) ;z Se Table of Contents . Please tabl e of contentsso that sections match referenced pa3es .

2 . Page Scope of Work/Planned Site =;ctiv(:ties_ -he

anticipated duration of field activities is not discussed . (8 CCR

5"192 (c) (4) (C) .

3 . Page 1-, Radiation . 90Sr is considered to be a primary beta

emitter only . Please include language Y:i`thin this section

ssflrfi_h p

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describing how beta particle screening shall be accomplished . (8CCR 5192 (c) (6) (A )

4 . Page 15, Site Characterization . SWWJ 4 .5 : LOX Plant FormerWaste Oil Sump and Clarifier- Please clarify statement"Anticipated chemicals refer to those chemicals that weredetected above screening or action levels during the previoussampling or that will be sampled for during the RFI" . Pleasedefine screening and action levels and discuss the method(s) usedto derive them and their significance relating to potentialoccupational exposures .

S . Page 30, Table 3, Summary of Physical and Operational SafetyHazards, Electrocution .

A) When heavy equipment (i .e . drill rigs) is used on siteswhere high voltage overhead power lines may be encountered,the minimum safe distances to be maintained from these linesare outlined in 8 CCR 2946 must be followed . Please modifyas indicated . ( 8 CCR 2946) .

B) Procedures describing borehole clearance are notdiscussed in sufficient detail . 8 :CR 1541 requires thatall regional notification centers be contacted a minimum oftwo working days prior to the start of any digging orexcavation work .

6 . Page 30, Table 3, Summary of Physical and Operational SafetyHazards, Heat Stress . Please provide greater detail describingTo :itoring protocols for heat-related disorders such as pulsemonitoring or aural temperature monitor__n:g procedures . Ensureaction levels, time frames and reference. : are included .

Pane 30, Table 3, Summary of Physical and Operational Safet•~~razards, _tat Stress . Description of nc-se hazards andcorresponding monitoring procedures to be employed on site

rerui_es clarification and/or modificat_zn . P.n employer isobligated to quantify their emplcvees' ex•_aosure to noise when

there is a cossibilli y of exposure to an eight-hour time-weightedaverage of 85 dEA . Provide personnel monitoring data fro mp_ o s -m:lar site activities or describe noise monitoring~rotocoic to be employed on site, inclu _nc a description of theinstrumentation, frequency of mon ;-torinc . and correspondingaction ie-.els . 8 CCRGeoup 75, Article =05 (Control of Nois e

Pace 31, Hazard !alysis of Field Casks, S7t ~=eccnus ssance, Personal Protective Eou_ument . Level D personalprotective eouipment (PPE), outlined within this section does notin :icate the use of safety evewear as outlined on page 38,

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s4Vla SlepakRocketdyne RFI HASPOctober 23,1995Page 4

Personal Protective Equipment section . Please modify forconsistency . ( 8 CCR 5192(g)) .

9 Page 38, Illumination . Explain how adequate lighting shallbe provided during work activities . Ensure minimum illuminationintensities outlined in table H-l, 8 CCR 5192 (m) are provided .

10 . Page 41 , Table 5 , Air Monitoring Action Levels . Pleaseverify that organic vapor /acid gas respirator cartridge willprovide adequate protection for vinyl chloride up to the PEL . ( 8CCR 5192(j), and 8 CCR 5210 )

11 . Page 4 2, Decontamination Procedures . A description ofsanitary facilities which will be available to site personnel isnot Included . Please describe provisions for providing personnelwith adequate potable and non-potable water and toiletfacilities . ( 8 CCR 5192(n)) .

12 . Page 43, Emergency Contingency Plan . Please describe anyRocketdyne SSFL facility-specific emergency evacuation alarms andprocedures within this section . 98 CCR 5192(1)) _

13 . Page 44, Bloodborne Pathogen Exposure Control Plan . Includea discussion of training requirements specified for personnelu t potential occupational exposures to bloodborne pathogens

- 8 CCR 5193 .

1 A discussionofconfin_ ed space hazards and entryprocedures is not provided . Describe hazards associated withcc-fi-ed spaces and corres ponding entry procedures . If n o

__ed space entry is anticipated (i . e no utility vault oration entry) then include a section within the HA SP stating

--a : confined space haza_^ds do not exist . (8 CCR(4) 1 ) (9) & 5157 )

CONCLUSION S

The submitted HASP does not contain all of the elementssneclfred in 8 CCR, section 5792 . Areas identified asdeficien t

e corrected or clarified and resubmitted for furthert--_• . _ Recommendations are attached for review and

ration . Please reline or otherwise delineate anycation to this document ro facilitate a timely response

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`Carla SlepakRocketdyne RFI HASPOctober 23, 1995Page 5

OSA is available to participate in a meeting or conferencecall to discuss this document or related items . Thank you forthe opportunity to review this document . Should questions arise ,please contact Frank Parr at (310) 590-4956 .

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