# Enhanced Biodegr**ada tion a**  **t a**

**Fr actur**  **ed R ock Sit**  **e**

**USEP A**  **- USGS**  **Fr actur**  **ed Ro**  **ck W orkshop**  **EP A R**  **egion 2**  **14 January**  **2014** 

# To **m Imbrigiot**  **ta and Clair**  **e Tiedeman, USGS**

# Bioaugmen **tat ion Basics** 

 

### Concept  **Inject bacteria and f** **ood**  **Bacteria populations incr**  **ease, and thus degr**  **adation r ates increase**   

### Adv **antages**  **Chlorinated solvents degr aded in situ**  **– substantial**  **concentr ation**  **re ductions**  **can be achieved**   **Po ssible r**  **educed need f** **or pump & tr eat**  **– lower**  **ener gy and tr**  **eatment cos ts**   

### Challenges  **Difficult to dis tribute amendments**  **over lar ge**  **volumes of the subsurf ace**   **Uncertainty in this dis**  **tribution, due t o tr**  **ansport path uncertainty**  **in fr actur**  **ed r ock**   **Sus tainability of enhanced**  **biodegr adation**  **– electr**  **on donor (food) ma**  **y become limiting**  **Po ssible**  **biof ouling**  **2 Enhanced**  **Biodegr adation at a Fr** **actured Ro**  **ck Sit e** 

**TCE**  **cis DCE**   **VC**  **Ethene**

+ Cl - + Cl - + Cl **Reductive Dechlorination** **Inject Pump** 

**Electron Donor &**  **Microbes** 

# Bioaugmen **tat ion**  **Experimen t**  **in Highly Con**  **ta mina**  **te d Muds**  **to nes** 

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 3**  

### Questions related to h **ydrogeology**

 **Expected tr ansport pa**  **ths?**  **Pumping rate**  **a t e**  **xtr action well?**   **Wher e to monitor?**   **Vo lume of amendments to inject?**   

### Char **act eriz**  **ation activities**  **Detailed str** **at igr** **aphic fr** **amework**  **Single & cr oss**  **- hole h**  **yd ra**  **ulic testing**  **Cross -**  **hole tr acer testing**   **Flow and tr** **ansport modeling**  **Push -**  **pull tr** **acer testing** 

# Char **act eriz**  **at ion**  **fo r**  **Bioaugmen tat**  **ion Design**  **Inject Pump** 

**Electron Donor &**  **Microbes**

**4 Enhanced**  **Biodegr adation at a Fr** **actured Ro**  **ck Sit e** 

# Cr **oss -**  **Hole Tr**  **acer T**

**es ting** 

**5 Enhanced**  **Biodegr adation at a Fr** **actured Ro**  **ck Sit e**  **Inject 3700 mg/L Bromide**  **Pump**



### Conclusions:
• **Huge dilution at pumped w**  **ell: only**  **s mall**  **amount of pumped water**  **is coming from the**  **region betw een**  **36BR & 15BR.**
• **> 80% of**  **mass still in aquifer**  **after 5 months**  **?**

# Tr **acer T**

**es ting: Br**  **omide in Aquif er**  **7 Mon ths a**  **ft er Injection** 

**Conclusions:**
• **Most of mass is in**  **dow ndip**  **region**  **low -**  **K rocks/fractures**  **strongly retain**  **tracer .**  **6 Enhanced**  **Biodegr adation at a Fr** **actured Ro**  **ck Sit e** 

###  

# No need t **o chang e**  **pumping ra**  **te at**  **1 5BR**   

# Mus **t inject lar ge**  **enough vo**  **lume so amendmen ts**  **ar e pushed t**  **o 73BR**  

# Subsequent push **- pull**  **tr acer t**  **es t es**  **ta blished**  **needed v olume**  

# Tr **acer T es**  **ting Inf ormed**  **Bioaugmen tat**  **ion Design**  **Inject Pump** 

**7 Enhanced**  **Biodegr adation at a Fr** **actured Ro**  **ck Sit e** 

# Bioaugmen **tat ion**  **Implemen tat**  **ion**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 8**  **Injection bladders** 

**EOS Water**  **- quality**  **monitoring**

###  

# Can g **eochemical & micr**  **obiological chang es**  **be obser ved downgr**  **adien t?**   

# How much an e **ff ect will it ha**  **ve and how long will the e**  **ff ects las**  **t?**  

# Do the bact **eria and electr**  **on donor mov**  **e?**  

# How f**ar aw ay** **ar e lat**  **er al**  **eff ects f** **elt?** 

# Ques **tions About E**  **ff ectiv**  **eness of Bioaugmen**  **tat ion**  **in Fr actur**  **ed Ro**  **ck**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 9** 

# Can or**ga nic**  **ge ochemic**  **al chang**  **es be obser**  **ve d in**  **downgr adien**  **t we**  **lls?**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e**



### - **Significant cisDCE**  **increases seen**  **in these same wells**  **- Significant TCE decreases**  **seen in wells 18 m and 30 m down the flow path** 

**31,000 340**  **19,000**

**900 11,000** 

**4,900 5,000** 

**3,600 Red:**  **median TCE**  **conc (**  **μg/l) pre**  **- bioaug**  **Blue: TCE**  **conc 4.8 years**  **post -**  **bioaug**

**TCE Reductions**

**- Significant TCE decreases**  **seen in wells 18 m and 30 m down the flow path** 

**3,600 59,000**  **6,400**

**22,000 2,400** 

**6,000 5,000** 

**3,400 Red:**  **median cisDCE**  **conc (**  **μg/l) pre**  **- bioaug**  **Blue: cisDCE**  **conc 4.8**  **years post**  **- bioaug** 

**cisDCE Production** 

**10**

# Can or**ga nic**  **ge ochemic**  **al chang**  **es be obser**  **ve d in**  **downgr adien**  **t we**  **lls?**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e -**  **Significant TCE decreases seen in wells 18 m and 30 m**  **down the flow path**

**2,700 5,100**  **4,900**

**130,000 1,600** 

**6,000 1,400** 

**1,400 Red:**  **median Fe**  **+2 conc**  **( μg/l)**  **pre -**  **bioaug Blue:**  **Fe +2**  **conc 4.8 years**  **post -**  **bioaug Ferrous Iron**  **Production**

**- Significant TCE decreases**  **seen in wells 18 m and 30 m down the flow path** 

**21 2**  **17**

**<1 28** 

**25 55** 

**47 Red:**  **median SO**  **4 conc**  **( mg/l**  **) pre**  **- bioaug**  **Blue: SO**  **4 conc**  **4.8 years post**  **- bioaug** 

**Sulfate Reduction** 

### - **Fe +2**  

### increases **& SO 4**  

### decreases **seen in wells**  **18 m and 30 m down**  **the flow**  **path**

**11**

# How much of an eff**ect will the bioaugmen**  **tat ion**  **ha ve**  **?**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 12**  **- Cl**  **production/ CVOC degradation**  **peaked ~7 months after injection.** 

**- Bioaugmentation**  **has increased Cl**  **production/CVOC degradation by**  **factor of 4 -**  **5 times natural attenuation.** 

# How much of an eff**ect will the bioaugmen**  **tat ion**  **ha ve**  **?**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 13**  

### - **Cl production**  **in first down**   ** gradient** **well is**  **combination of**  **upgradient Cl**  **and bioaug**  **Cl.**

**- Cl**  **production/ CVOC**  **degrada**   ** tion** **continuing at high**  **level.**

**- Implies**  **continuing TCE**  **source and**  **favorable redox conditions.** 

# How long will the eff**ects of bioaugmen**  **tat ion**  **las t?** 

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 14**  

### - **TCE degraded & cisDCE**  **produced quickly** 

**- VC**  **& ethene produced after**  **lag period**

**- cisDCE =**  **VC since ~1 yr**  **post -**  **injection**

**- Continuing**  **source of TCE**

# How long will the eff**ects of bioaugmen**  **tat ion**  **las t?** 

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 15**  

### - **Increased DOC**  **(EOS surrogate) not yet back to**  **pre -**  **injection levels** 

**- Lactic acid**  **used up after ~2.5**  **years**

# Do the bact **eria mov e?** 

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e**

**- Significant TCE decreases**  **seen in wells 18 m and 30 m down the flow path** 

**Dhc 10**  **4 10**  **8 Red:**  **median bacteria copies/L pre**  **- bioaug**  **Blue: max bacteria**  **conc 3.8 years post**  **- bioaug** 

**Geo 10**  **6 10**  **10 Dhc** 

**10 5**  **10 7**  **Geo 10**  **7 10**  **9 Dhc** 

**10 6**  **10 7**  **Geo 10**  **6 10**  **8 Dhc** 

**10 5**  **10 5**  **Geo 10**  **5 10**  **5** 

### Dehalococcoides **and Geobacter**  **Increases**

**- Dhc & Geo increases**  **seen in both 18 m and**  **30 m downgradient wells**  **16**

# Does the electr **on donor mov e?** 

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 17** 

**- Significant TCE decreases**  **seen in wells 18 m and 30 m down the flow path** 

**5.9 73.7**  **Red: median DOC**  **conc (mg/L) pre**  **- bioaug**  **Blue: max DOC**  **conc 3.8 years post**  **- bioaug** 

**20.0 44.5**  **0.9**

**1.6 1.2** 

**2.2** 

### DOC Concentrations15BR 71BR 73BR 36BR

80BR 

# Lateral effects

**18**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 10 m** 

# Wha **t is the la te**  **ra l e**  **xt en**  **t of the eff ect**  **of bioaugmen**  **tat ion**  **?**

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 19**  

### - **Packers separate**  **GW with very**  **different WQ**  **effectively**

**- Areal effect of**  **bioaugmentation is**  **<10 m laterally**

**- Bacteria from**  **bioaugmentation have not reached**  **any zone in 80BR** 

**- TCE:cisDCE >1 in**  **80BR TCE 820**  **cisDCE 2700 Dhc 10**  **5**
**TCE 120 cisDCE 22000**  **Dhc 10 6** 

**TCE 5700 cisDCE 9600**  **Dhc 10 4**  **TCE 2000 cisDCE 1200**  **Dhc <10 1** 

**TCE 4300 cisDCE 1900**  **Dhc 10 2** 

**TCE 2300 cisDCE 1300**  **Dhc <10 1**  **80BR 73BR** 

**A**

**B**

**C D1** 

**D2**

**E 10 m** 

###  

# Fr **actur ed**  **ro ck flow paths**  **mus t**  **be iden tified**  **using aquif** **er tests and tr acer t**  **es ts.**   

# Geochemical **eff ects of**  **bioaugmen tat**  **ion were**  **obser ved up to 30 m**  **downgr adien**  **t fr**  **om injection well along**  **a flow path.**  

# Ef**fe cts not**  **ed included incr**  **eased re**  **ductiv e**  **dehalog ena**  **tion ,**  **mor e r**  **educing conditions,**  **br eak**  **down of electr on donor**  **, and pr esence**  **of incr eased**  **bact erial**  **concen tr**  **ations.** 

# Conclusions

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 20** 

###  

# Electr **on donor and bact eria**  **can be tr**  **ansport ed**  **a limit ed**  **dis ta**  **nce along**  **flow path by injection**  **and pumping.**  

# Bioaugmen **tat ion**  **incr eased**  **Cl pr**  **oduction/ CV**  **OC degr adation**  **by f act**  **or of 4 -**  **5x ov er**  **natur al**  **attenuation.**  

# Bioaugmen **te d**  **biodegr ada**  **tion w as s**  **till significan**  **t in injection**  **well and s till**  **st ro**  **ng 18**  **m downgr**  **adien t**  **after almos t**  **5 y ear**  **s.** 

# Conclusions

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 21** 

###  

# Bioaugmen **te d**  **biodegr ada**  **tion of TC**  **E fr**  **equently stalls at cisDCE**  **after relatively short period of time (6**  **- 12 mon**  **ths).**  

# Later **al spr**  **ead of bioaugmen**  **tat ion**  **eff ects**  **depends on he te**  **ro ge**  **neity of flow and tr**  **ansport paths**  **in the fr actur**  **ed ro**  **ck.** 

# Conclusions

**Enhanced Biodegr** **adation at a Fr actured**  **Ro ck Sit**  **e 22**