The initial test results of an EPA study in 1989 and 1990 were not conclusive about the value of biostimulation of indigenous microbes and about the use of exogenous bacteria for remediation. In contrast, a later field study in Delaware reached the following conclusions:a. Biostimulation can slow down hydrocarbon removal. b. Exogenous bacteria outcompete indigenous bacteria. c. Biostimulation can accelerate hydrocarbon removal. d. Addition of exogenous bacteria leads to faster hydrocarbon cleanup than biostimulation.

The correct answer is (C).

Explanation:

Biostimulation can accelerate Hydrocarbon removal.Biostimulation includes the adjustment of nature to animate existing microscopic organisms fit for bioremediation. This should be possible by expansion of different types of rate constraining supplements and electron acceptors, for example, phosphorus, nitrogen, oxygen, or carbon (for example as molasses). Then again, remediation of halogenated contaminants in anaerobic conditions might be animated by including electron benefactors (natural substrates), in this manner permitting indigenous microorganisms to utilize the halogenated contaminants as electron acceptors.

The sun is 432,170 mi big!